Class LJ^ llZ , 
 
 PRKSENTCl) BY 
 
CHILD 
 BEHAVIOR 
 
 A CRITICAL AND EXPERIMENTAL STUDY OF 
 
 YOUNG CHILDREN BY THE METHOD 
 
 OF CONDITIONED REFLEXES 
 
 BY 
 
 FLORENCE MATEER, A.M. 
 
 A Dissertation submitted to the Faculty of Clark University, Worcester, 
 Mass., in partial fulfillment of the requirements for the degree of 
 Doctor of Philosophy, and accepted on the recommen- 
 dation of William H. Burnham 
 
CHILD 
 BEHAVIOR 
 
 A CRITICAL AND EXPERIMENTAL STUDY OF 
 
 YOUNG CHILDREN BY THE METHOD 
 
 OF CONDITIONED REFLEXES 
 
 BY 
 
 FLORENCE MATEER, A.M. 
 
 A Dissertation submitted to the Faculty of Clark University, Worcester, 
 Mass., in partial fulfillment of the requirements for the degree of 
 Doctor of Philosophy, and accepted on the recommen- 
 dation of William H, Burnham 
 
 ^¥6 
 
 BOSTON 
 RICHARD G. BADGER 
 
 THE GORHAM PRESS 
 
COPYEIGHT, 1918, BY RiCHARD G. BaDGER 
 
 All Rights Reserved ^ ,^ \ 
 
 YA^I-' 
 
 Gilt ^ 
 
 Made in the United States of America 
 
 The Gorham Press, Boston, U.S.A. 
 
CONTENTS 
 
 CHAPTER PAGB 
 
 Introduction 7 
 
 I Historical Survey of Child Study . . 13 
 
 II Methods and Results of Child Study . . 82 
 
 III Behaviorism and Child Psychology . . 53 
 
 IV The Experiments of Krasnogorski . . 73 
 
 V Methodology and Technique Modified 
 
 FROM Krasnogorski . . . . .94 
 
 VI Preliminary Experiments and their Indi- 
 cations . . . . . . .113 
 
 VII A Quantitative Study of the Conditioned 
 
 Reflex . . . . . . .137 
 
 VIII Conclusions 196 
 
 Curves Illustrating the Development of 
 Conditioned Reflexes .... 209 
 
 Selected Records from Other Cases . .215 
 
 Bibliography 219 
 
INTRODUCTION 
 
 "Child Study" is a term so well-worn and s dely 
 used that its application and meaning in any one in- 
 stance consequently needs definition. Studies are made 
 of the growth of the child, his games, his vor bulary, 
 his mental activities, and they are all legitimate 
 branches of child study, somewhat overlapping, it is 
 true, and all of them far more fragmentary than 
 complete. 
 
 One of the lines along which a great deal of work has 
 been done is that of the mental activities of the child 
 or on what might justly be called child psychology. 
 This division is recognized from the standpoint of psy- 
 chology itself and is again given varied connotations 
 as it deals with different features of the subject. All 
 of these subdivisions have, however, one thing in com- 
 mon. They treat of the growing organism as con- 
 trasted with the predominantly functioning organism 
 of the adult. Bearing this characteristic in mind, child 
 psychology may be justly said to include the study of 
 all the stages of the intellectual development of the 
 organism previous to the stage of complete maturity of 
 mind. Usage has rather clearly discriminated for us, 
 however, three main divisions in this long period of 
 development. These are usually studied separately, al- 
 though not without relating the findings of any one 
 period to those of the others. 
 
 The most widely known and best developed of these 
 three divisions of child psychology is educational psy- 
 
 7 
 
8 INTRODUCTION 
 
 chology or psychology as it applies to the child of 
 school age and consequently to his education. Partly 
 overlapping this but separated from it by the rift of 
 enormous physiological changes is the psychology of 
 the adolescent. In its turn the study of the mind of 
 the adolescent can be separated from the study of the 
 mind of the adult only by rather artificial discrimina- 
 tions. 
 
 On the other extreme of the age-limits of childhood 
 we have the child of the pre-school age. Here the term 
 "Child Study" is generally used whether or no the prob- 
 lem attacked is a psychological one. In view of the 
 tremendous development of intellect that occurs in this 
 period and considering the large number of studies of 
 such development that have already been made, it seems 
 logical to use the term "Psychology" in distinguishing 
 these studies from investigations dealing with physical 
 development, social reactions, and sense functioning, 
 despite the fact that there are necessary correlations 
 which must be considered. 
 
 But psychology must itself be defined. Shall the 
 term be used to designate any type of study which de- 
 scribes the child's mental processes through observation, 
 analogy, interpretation, and experimentation or shall 
 the usage be more limited? In so far as one wishes to 
 be scientifically accurate and in accord with the ac- 
 cepted meaning of to-day the term should be used only 
 to indicate the report of observations made under con- 
 trolled conditions which are such that the experiments 
 may be repeated and the results verified by any com- 
 petent person at any future time. 
 
 Even so the term "Psychology" has a connotation 
 which is very apt to be misleading when applied to the 
 study of young children. Psychology deals with mental 
 
INTRODUCTION 9 
 
 processes, with images, ideas and judgments. These 
 the young child can not report to us, nor can we study 
 them directly in their functioning in him, but only 
 through inference, deduction and analogy. Results 
 obtained thus are not scientific in the sense of the 
 natural sciences. The animal psychologists have met 
 and conquered this same situation and now study the 
 behavior of their subjects without dependence upon the 
 assumption of such and such subjective processes. 
 They are content to ascertain the exact relations ex- 
 isting between stimulus and reaction. It seems fairly 
 logical that those wishing to enroll the study of the 
 young child among the sciences should take the same 
 step, should be content to study his behavior. Of course 
 in its wider meaning this would include all the activi- 
 ties of the child but in a stricter sense we may use it 
 to mean the study of more or less complex reaction 
 to definitely ascertained stimuli. 
 
 The term "Child Behavior" will therefore be used in 
 this discussion to indicate the observations of and the 
 experimentations upon the mental processes of children 
 under school age, as expressed in their behavior or re- 
 action to stimuli and ascertained under conditions per- 
 mitting repetition and verification. But the value of 
 any such study will be greatly increased if several ad- 
 ditional factors are taken into consideration. The 
 problem on learning, memory, language, or anything 
 else will be far more valuable if it is studied in connec- 
 tion with full recognition and evaluation of the physi- 
 cal organism, the environmental conditions, and the 
 past experiences of the child. Also, the problem under- 
 taken, whatever it is, should be correlated with and 
 compared with similar studies on older children. 
 
 Moreover, if we are attempting to formulate a basis 
 
10 INTRODUCTION 
 
 for a science of Child Behavior, there are a few ques- 
 tions we should ask before undertaking any specific 
 investigation. The answers to these questions will un- 
 doubtedly indicate the most probable lines of profitable 
 work. The questions are the following. What work 
 has been done and what results have been obtained re- 
 garding the mental development of the young child.'' 
 To what extent do these investigations fail and what 
 are the reasons for their errors .f* What improvements 
 in technique, apparatus and method can be made in the 
 new work to be done? 
 
 Then, when a piece of research has been completed, 
 the results should be evaluated not only from the stand- 
 point of the absolute findings but also from the stand- 
 point of their interpretation, their significance for 
 science in general and, in this age of applied values, 
 from the standpoint of their use. Also, every problem 
 should give, as a result of its being intimately known 
 through experience, suggestions for modifications of 
 use in future experiments and also suggestions for new 
 but correlated investigations. 
 
 Let us here attack these problems in the order men- 
 tioned, trying to explain more fully by example just 
 what is meant. First, in order to avoid duplication and 
 to avail ourselves of the best that the experience of 
 past experimenters has to offer we must survey the 
 results so far obtained by those studying the young 
 child. These results will be found in the various books 
 on "Child Study." 
 
CHILD BEHAVIOR 
 
CHILD BEHAVIOR 
 
 CHAPTER I 
 HISTORICAL SURVEY OF CHILD STUDY 
 
 IT would be interesting to trace the evolution of the 
 place the child has played in human thought and 
 plans since the earliest days of recorded events but 
 that would lie a little aside from the main purpose of 
 this discussion. 
 
 All we can do here is indicate the more important 
 factors in the development of child study and see how 
 they give rise to child psychology as a separate line of 
 research and theory. 
 * The place of the child was ideal in the days of Hellas ; 
 statesmen, philosophers and citizens in general were 
 devoted to his interests and gave of their best to his 
 training. To them this appeared as but natural since 
 he was the future State and only through giving him 
 the most perfect preparation would the future State 
 be as mighty as possible. Schools were pleasant places 
 and the lessons of the Greek boy would seem play to 
 the present-day child, but one great principle appears 
 to have been disregarded. The boy was trained as a 
 part of the group, the goal to be reached subserved 
 the purpose of the group and the child as an individual 
 was unrecognized. 
 
 13 
 
14 CHILD BEHAVIOR 
 
 A With Christianity the child sank into obscurity. The 
 same faith which elevated one child to Divinity made 
 all other children sinful in their very nature and the 
 Dark Ages could from the standpoint of the child have 
 had no other cognomen. The stress was everywhere 
 other-worldly, although this gradually changed as the 
 Renaissance dawned and glimpses of brighter things 
 may be seen. 
 
 ^ The first ray of light which we can point out ob- 
 jectively as indicating the advent of a better day is 
 the appearance of the Orbis Pictis of Comenius in 
 1658. This first picture book for children shows us 
 several things. The child is coming once more into the 
 focus of attention and he is regarded as a creature 
 having some interests peculiar to himself which must 
 be met in a way adapted to him. The stern necessity 
 of making him an honorable and righteous man is now 
 seen to be not incompatible with making him more 
 happy as a child. Perhaps we might appear to be de- 
 ducing too much from the advent of this book were it 
 not that the same spirit is reflected throughout all the 
 rest of the writings of Comenius, while the little book's 
 immediate use and popularity throughout Europe 
 seem to indicate that the people were ready for it. 
 Nevertheless, another hundred years elapses before we 
 find a generalized and definite expression of the rights 
 of the child. This we owe to Rousseau. 
 
 With the appearance of the Emile in 1762 we have 
 the beginnings of real child-study, both theoretical, 
 educational and observational. We can do no better 
 than let the author speak for himself. In the preface 
 to the Emile he writes: "It (the Emile) was begun to 
 give pleasure to a good mother who thinks for her- 
 self . , . We know nothing of childhood; and with 
 
SURVEY OF CHILD STUDY 15 
 
 our mistaken notions the further we advance the further 
 we go astray. The wisest writers devote themselves 
 to what a man ought to know, without asking what a 
 child is capable of learning. They are always looking 
 for the man in the child, without considering what he 
 is before he becomes a man. It is to this study that I 
 have chiefly devoted myself. ... I may be greatly 
 mistaken as to what ought to be done, but I think I 
 have clearly perceived the material which is to be 
 worked upon." (145, p. 1.) 
 
 ' Rousseau's estimation of his own work may be ac- 
 cepted to-day. Education according to his plan, elimi- 
 nating the natural social relations and demanding a 
 laborious trial and error method of finding knowledge, 
 may appear very far from ideal but the demand that 
 the child be allowed free activity from the time of birth, 
 with careful consideration and individual study; the 
 insistence upon the fact that the child has certain 
 rights of his own; the keen observations of child na- 
 ture; all show that he indeed had grasped the signifi- 
 cant features of the situation and recognized in the 
 study of the child himself the solution of the problems 
 of the child and of the future man. We might trace 
 his influence upon human thought from that day to this 
 but we must here narrow our study to tracing only the 
 written records of the more influential students of the 
 child since the time of Rousseau. 
 
 " The earliest records of observations of the develop- 
 ment of young children are probably those made by 
 Pestalozzi (134) during the year 1774 upon his little 
 son who was then just three and a half years old. They 
 are not primarily psychological but a homely diary 
 of the father's attempts at educating the child, inter- 
 spersed with keen observations regarding his develop- 
 
16 CHILD BEHAVIOR 
 
 ment mentally. It is significant that although Pesta- 
 lozzi thought too little of it to publish it, this frag- 
 ment of observations contains much that would be con- 
 sidered praiseworthy to-day. It is the humane, per- 
 sonalized document of a man who wrote not as an ab- 
 stract scientist but as one who knew people and who 
 loved children. But, just as Pestalozzi was interested 
 primarily in the tendencies and abilities of children in 
 general in order to better formulate, upon them as a 
 basis, his principles of education, so here, also, the ob- 
 servations in themselves are only a means to an end. 
 We must not forget that to Pestalozzi the child was 
 merely the immature and future man. To quote Heu- 
 baum, "Pestalozzi had not grasped the truth that the 
 age of childhood had significance and value in and for 
 itself, that it carries its end and purpose in itself" 
 (78, p. 366). 
 
 And so Dietrich Tiedemann (174) is the real founder 
 of child study. His observations of the development 
 of his son appeared in 1787. They are purely psy- 
 chological and reflect the empirical attitude of the 
 times. Tiedemann deplores the fact that there are not 
 more studies of these early manifestations of the de- 
 velopment of the mental abilities because through such 
 studies that part of the theory of the soul which studies 
 the development of the various mental abilities in man 
 would be considerably advanced and hence it would 
 further pedagogy which is necessarily based upon it. 
 The study, despite its excellence, attracted very little 
 attention, sank into oblivion, and was not rescued until 
 Michelan published a French translation of it in the 
 Journal general de Vmstruction piMique in 1863. 
 
 Tiedemann's "Die vier erste Jahre meiner Kinder" 
 (175) does not seem to have been any more influential 
 
SURVEY OF CHILD STUDY 17 
 
 until it, also, was re-published in the same journal, 
 the same year. 
 
 Froebel's "Die Menschenerziehung" (49) appeared 
 in 1826. This, again, is the work of one who studies 
 the young child motivated by the desire to obtain a 
 factual basis for the development of a system of edu- 
 cation. His observations are a mixture of empiricism 
 and philosophical inferences. One new step he takes 
 is of special significance from our standpoint. He 
 points out that the child, the boy, the youth are not 
 distinct stages but that they are continuous and that 
 transitions are unbroken. Hence he speaks of "man in 
 the period of earliest childhood." 
 
 In the same year Schleiermacher was expressing his 
 views on childhood and education in his lectures at the 
 University of Berlin. To him we owe the first com- 
 plete formulation of the modern or Rousselian attitude 
 towards the child which, in spite of the influence that 
 his lectures must have had, develops very slowly aside 
 from the secondary consideration that it receives in 
 educational theory. Too much credit can hardly be 
 given to the man who formulated the theory that "just 
 as each period of Hfe is for itself a natural division of 
 life and has its own definite character: so, also, should 
 each of these periods be enjoyed in its own specific 
 character and not be regarded simply as a means to a 
 later period" (147, p. 317). 
 
 The immediate followers of Schleiermacher do not 
 seem to profit by, nor to even be cognizant of, the im- 
 mense advance which his attitude indicates. 
 
 In 18S8 Mme. Necker de Saussure published the first 
 volume of her "Education Progressive" (1^1) in which 
 she treats of the first four years of life. The second 
 volume appeared in 1832 and carries the child beyond 
 
18 CHILD BEHAVIOR 
 
 the age with which we are concerned here. Mme. 
 Necker's observations of the development of mental 
 abilities in young children are extremely fascinating, 
 being filled with the spirit of one who wrote with an 
 understanding of her subject matter, and they de- 
 serve wider recognition than they have received in this 
 country. But, although the observations she records 
 are fairly accurate, they are not made from the stand- 
 point of a study of the child for the child's sake. Her 
 self-confessed motive is a book on Christian education, 
 the "constantly progressing education," not completed 
 in this life. Her study of the child is primarily to 
 obtain information as to which of the moral faculties 
 develops first and what the order is of those that fol- 
 low. The child is only the future man as man himself 
 is but a transient here, preparing for the spiritual life 
 to come. 
 
 Throughout this period, and even preceding it we 
 find biographies and autobiographies which are literary 
 rather than truthful, fanciful rather than practical. 
 They are often rated among the books on child study 
 but to place them there is rather dangerous unless one 
 realizes that they are a type in themselves. A good 
 illustration of this tendency which shows by contrast 
 with these other early studies how long-distanced the 
 method is and how much less valuable and effective from 
 the scientific standpoint is Goltz' "Buch der Kindheit 
 (Selbstbiographie)" (64). This has been widely read 
 by German parents and yet it is not scientific or even 
 methodical in its treatment. This book appeared in 
 1847. 
 
 In 1851 Lobisch's work, "Die Entwicklungs- 
 geschichte der Seele des Kindes" (106), appeared. 
 This book seems to have had great influence if we may 
 
SURVEY OF CHILD STUDY 19 
 
 judge by the number of times we find it quoted. 
 Lobisch was a physician specializing on children's dis- 
 eases and probably in many ways one of the earliest 
 psychoclinicians. 
 
 The next significant publication was Sigismund's 
 "Kind und Welt" (159). It appeared in 1856 and is 
 one of the most delightful and suggestive books ever 
 written on this subject. Studying his own child from 
 birth through the periods of development of laughing, 
 sitting, walking, and talking, Sigismund also compares 
 its development with that of other children among his 
 acquaintances. He gives the first suggestion of a 
 genetic attitude and is not concerned as almost all 
 before him have been, with educational applications. 
 He touches upon the manifold topics of sensory and 
 motor development while his observations regarding 
 language and affective development are very creditable. 
 
 Hey f elder's (79) work, which is valuable chiefly be- 
 cause of his observations upon speech, appeared during 
 the next two years. This is the first of the articles 
 which tend more or less completely to select some one 
 form of mental activity as their subject matter. 
 
 To Kussmaul (102) writing in 1859 we owe the first 
 application of the extensive method to child study. 
 Limiting himself to the study of the newly-born infant 
 he makes the first generalized statements of mental de- 
 velopment in young children that are based upon ob- 
 servations upon a number of cases. 
 
 From this time on the development of child study is 
 much more rapid and the number of contributions be- 
 comes within a few years so voluminous that a complete 
 bibliography of them, without any annotations, would 
 far exceed this volume in size. 
 
 In 1869 the Berlin Padagogische Verein issued a bul- 
 
20 CHILD BEHAVIOR 
 
 letin urging teachers to study the children entering 
 school in order to ascertain their range of ideas and 
 thus glimpse their individuality and range of experi- 
 ence. In spite of lack of enthusiasm and, in many in- 
 stances, the inability to make competent reports, the 
 results obtained were most illuminating and valuable. 
 They showed the appalling lack of knowledge concern- 
 ing things children were supposed to have grasped just 
 because they were within range of observation. Indi- 
 vidual differences were markedly shown, imitation was 
 found to influence the group answers and yet the com- 
 plexity and fascination of the findings reported by Bar- 
 tholomai and Schwabe (9) were undoubtedly effective 
 in stimulating further study of the child as he is be- 
 fore coming under school influences. 
 
 The work of Bartholomai and Schwabe was followed 
 by that of Lange (103) in 1879 and the influence ex- 
 tended to America by the similar study made by G. 
 Stanley Hall on Boston children in 1880 (70). This 
 was the first systematic study of the mind of the child 
 made in America. Similar work has since been done 
 by Netschajeff (122) in Petrograd. 
 
 In 1873 Genzmer (54) published his verification of 
 Kussmaul's study and this was followed in 1882 by 
 Kroner's (101) work on the same subject. This phy- 
 sio-psychological study of the sensory development of 
 the young child has become one of the most frequently 
 pursued branches of child study. Several illustrations 
 will suffice to show the height of this development. The 
 recent work of Canestrini (26) is noteworthy. He 
 not only uses an objective method but studies a large 
 group, seventy, of children under both waking and 
 sleeping conditions, with due regard for any change in 
 the conditions of environment or in the child's physical 
 
SURVEY OF CHILD STUDY 21 
 
 or emotional state. 
 
 Perhaps an even more careful study in an allied field, 
 developed out of this, is that of Benedict and Talbot 
 upon the "Physiology of the New-Born Infant" (11). 
 They have studied the metabolism of one hundred new- 
 born babies and have carried out their work in such 
 careful detail that they can suggest certain procedures 
 for the conservation of energy and supplemental feed- 
 ing during the first week of life. 
 
 Taine's (169) brief note upon the acquisition of 
 language in children and in the race is of interest for 
 several reasons. It voices the genetic attitude and at 
 the same time, since it comes to us from France, shows 
 that Germany and Austria are not alone in progress 
 in their new interest in the child. Moreover, this ap- 
 peared in 1876 and a part of it was translated and 
 published in the English journal Mind the next 
 year. Darwin's "Biographical Sketch of an Infant" 
 (34) appeared in the next number of the same maga- 
 zine, its publication stimulated as he himself tells us 
 by reading Taine's article. Written thirty-seven 
 years before it was nevertheless, despite the delay, the 
 first published product of English child study. This 
 shows how little known and valued the earlier conti- 
 nental writers must have been among their British 
 neighbors. 
 
 But bigger, more suggestive studies were soon to 
 appear. In 1878 Perez published his book entitled 
 "Le trois premieres annees de 1' enfant" (132). The 
 results of careful study are here combined with the 
 logical, brilliant style of the French writer. Perez, 
 while conforming to all rules for "scientific" writing 
 of his time, yet gives such a fascinating study that 
 the rapid demand for new editions of this book does not 
 
22 CHILD BEHAVIOR 
 
 seem remarkable. 
 
 He, first, seems to have felt the need of extending 
 such observations over the whole of the pre-school 
 period and so continues his study under the title 
 "L'Enfant de trois a sept ans" (183). This is not 
 quite as interesting as his first volume and has decid- 
 edly more of a pedagogical tendency but is worth not- 
 ing because of its historical primacy in this field. 
 
 Meanwhile another contributor has appeared, one 
 who usually, because of his greater value, has so over- 
 shadowed Perez that the priority of the latter and his 
 consequent influence upon the time are overlooked. This 
 is Preyer. In 1880 he published an article on Psycho- 
 genesis (140) which reveals him as an ardent evolu- 
 tionist and consequently we can anticipate the treat- 
 ment of his "Die Seele des Kindes" (141). He studies 
 his own child from birth on and besides observation in- 
 troduces a new element, experiments. These controlled 
 experiences allow of variation at will. Especially note- 
 worthy, although begun at a rather late age, are his 
 experiments upon color to which he was probably stim- 
 ulated by Allen's study of the color sense (1). 
 
 From this time on not only books but magazine 
 articles upon child study and especially upon the child 
 mind are so numerous that the detailed study of the 
 development in any one country, or of any one line of 
 investigation, would in itself necessitate extensive treat- 
 ment. It seems more fitting here to indicate the high 
 points in the chief branches of the many trends we 
 find developing out of this period. Several of these 
 have already been indicated. 
 
 Let us first survey the work in individual countries 
 briefly. 
 
 In Germany Preyer continued to be the leading 
 
SURVEY OF CHILD STUDY 23 
 
 authority for some time, interspersing his articles on 
 the psychology of the child with work on the physi- 
 ology of the embryo with especial consideration of the 
 manifestations of life before birth (142). However 
 we find him still writing in 1897 on the subject which 
 was so well developed in his earlier work, that is on 
 color discrimination (143). 
 
 The work of Ploss must not pass unmentioned. He 
 has achieved one of those marvelous compilations which 
 seem to need the German's plodding and indefatigable 
 application. Ploss gives us the first study of the so- 
 cial customs built up around and influencing the child 
 from the day he is born (136, 137). 
 
 The work of Vierordt (180, 181) must be men- 
 tioned, too. Although it is purely anatomical and 
 physiological in both its subject matter and aims, it 
 is the symbol of the great development of anthropo- 
 logical studies wliich give us the broader aspects of 
 child study though they do not contribute directly to 
 the psychology of the child. 
 
 Since then Ufer, Ament, Meumann and Stem have 
 done the most significant work. 
 
 Ufer has not only written much himself but has 
 also translated into German a considerable amount on 
 this subject. Ament has been interested especially in 
 child speech and in the history and development of 
 child psychology in general. It would hardly be com- 
 mensurate with the object of this sketch to attempt 
 here, in a form which would necessarily be brief, any 
 statement of the development which he has handled so 
 well in his "Forts chritte der Kinder seelenkunde 1895- 
 1903" (4). 
 
 Meumann, too, has contributed considerable to the 
 upper end of this fore-school period but his aims are 
 
24< CHILD BEHAVIOR 
 
 more pedagogical. 
 
 Stern is undoubtedly the most important, most sig- 
 nificant, as well as most voluminous German writer in 
 this field — Gutberlet (69) calls him the greatest of all 
 child psychologists of the present day. 
 
 The more recent writings, especially magazine con- 
 tributions, indicate new workers who will probably 
 supersede those just mentioned but whose work is not 
 yet very well tested by time. Among these we may 
 mention Dix (38), Schmidt (148), Buchner (21), Scu- 
 pin (150), DyrofF (41) and especially Groos (66), 
 while the careful, critical discussion of the psychology 
 of development in Ruttmann's (146) survey of modern 
 psychology is the most scientific and comprehensive 
 summary so far available, altho it deals somewhat too 
 exclusively with German contributions. 
 
 In Belgium the work has been confined to children 
 of school age and the problems studied have been peda- 
 gogical in their formulation. 
 
 In France Perez continued writing up until his 
 death but his discussions gradually became more philo- 
 sophical and less based upon observation. Compayre's 
 "L'Evolution intellectuelle et morale de I'enfant" (32) 
 has supplanted Perez's work and is the most recent 
 French publication which is general and comprehensive * 
 in its treatment. 
 
 Mere reference to the many valuable volumes of 
 UAnnee Fsychologique will show the varied interests 
 developed in this subject by Perez's countrymen. Binet 
 and his collaborators, especially Henri and Simon, have 
 accomplished much although nowhere do we find the 
 same type of work as among the Germans. The French 
 write brilliantly and convincingly but their technique 
 is apt to be at fault. They seem to hit intuitively upon 
 
SURVEY OF CHILD STUDY 25 
 
 right premises and conclusions, although their data 
 may be unconvincing or scanty. The German work is 
 more stolid, more convincing in its facts but less in- 
 spiring in application. 
 
 Among the lesser French writers of to-day we should 
 perhaps mention Vaschide, Bouquet (18), Boutan (19) 
 and Cramaussel (33). 
 
 The work on Child Study in Italy began with Luigi 
 Ferri. Interested in the work of Darwin and Taine, 
 he began studying a young child in regard to the de- 
 velopment of sense perception, attention, speech, imi- 
 tation, etc. His first results were published in 1879 
 (45) and were followed by others on the same child 
 (46, 47). His work raises in its discussion some inter- 
 esting philosophical questions. 
 
 Ottolenghi (125) studied skin sensitivity but largely 
 on older children. Garbini seems to have done the most 
 original and systematic of the Italian work. He 
 studied the voice of the child (50), changes in its pitch, 
 vibration frequency and duration of cries and he re- 
 cords the ages at which changes occur. He also did 
 intensive work on development of the color sense (51), 
 working on 557 children ranging from the new-born 
 up to those 60 months of age. His work (52) on de- 
 velopment of the olfactory sense on 10 new-bom in- 
 fants and 415 children between the ages of three and 
 six is equally valuable. Garbini is undoubtedly an ex- 
 ception among those who have studied children. His 
 work is thoroughly scientific and objective in method. 
 
 One other Italian writer needs special recognition 
 and that is Paola Lombroso. Besides some original 
 work on the instinct of conservation in children (109) 
 she has written a historical and critical account of the 
 work done by her fellow countrymen along the lines of 
 
26 CHILD BEHAVIOR 
 
 child study (108). The Italians have not so far pro- 
 duced any one study covering the whole period of child- 
 hood, Lombroso's book (107), which attempts this, be- 
 ing rather incomplete along some lines and quite lim- 
 ited in scope. 
 
 Russian literati re is in general so little accessible 
 that it is almost impossible to tell what has been ac- 
 complished in that country. Several names must be 
 mentioned, though. NetschajefF has written quite a 
 little in German magazines and has since 1904 had an 
 institute for Paidology in Petrograd. Sikorskij is 
 perhaps better known. The most recent of his writings 
 is his "Die Seele des Kindes" (160) published in 1902. 
 This has passed through three Russian editions but 
 owing to lack of translation of the third edition it is 
 impossible to state whether there are or are not new 
 contributions in it. The many changes in and addi- 
 tions to the second edition lead one to feel that the 
 author is still working towards, rather than resting on, 
 an ideal study. 
 
 He does not, however, seem to be familiar with, at 
 least he does not mention, the significance of the theo- 
 ries developed by his own fellow-countrymen, Pavlov 
 and his followers. 
 
 In England there was rapid development in child 
 study immediately following the publication of Dar- 
 win's sketch. Pollock's (139) work on language de- 
 velopment of an infant appeared in the following year 
 and was followed by the work of Champney (80) and 
 SuUy (166) on the same subject. With Sully this was 
 the beginning of a long period of steady contribution 
 to the subject and none of us needs to be reminded of 
 his "Studies of Childhood" (167). 
 
 Warner has done quite a lot to advance the methods 
 
SURVEY OF CHILD STUDY 27 
 
 of child study beginning with his ptiblication of "The 
 Children: How to Study Them" (183) in 1887. How- 
 ever, he aims chiefly at furthering educational methods, 
 and studies especially the physical and physio-psycho- 
 logical aspects of the subject. One significant attempt 
 of his should be mentioned. It is a brief report (182) 
 of an apparatus which he designed and used to measure 
 the spontaneous movements of the hands of children 
 and adults. He found that in infants probably spon- 
 taneous movements "can be arrested by light and also 
 by sound" (p. 162). He outlines a method for study- 
 ing the character of the modification and reports that 
 these modifications tend to occur regularly to the same 
 stimuli, illustrating the statement with curves from 
 his experiments. 
 
 Drummond (39, 40) is a more recent writer of a 
 rather elementary type of book intended evidently for 
 the inexperienced student. This type of contribution 
 is rather well illustrated in the pages of Child Studt/y 
 the official journal of the British Child Study Associa- 
 tion, while the magazine, The Child, is devoted to the 
 social, hygienic and educational welfare of the child. 
 In England this practical tendency seems to have rather 
 superseded the less material interest in child study it- 
 self. 
 
 There is, however, a small but valuable body of 
 studies lying partly within the limits of child psy- 
 chology. For instance McDougall's "Investigation of 
 the Color Sense of Two Infants" (115) not only gives 
 a higher development of method but is also a valuable 
 contribution showing that color development not only 
 comes earlier than Baldwin found but also that it is 
 readily studied. Although different in technique the 
 work of Myers (ISO) and Valentine (178) is similar. 
 
28 CHILD BEHAVIOR 
 
 On the whole English contributions to child study, in 
 so far as it deals with the child of pre-school age, have 
 been imitative rather than original and very scanty in 
 number. 
 
 The situation in America is different and appears 
 more so by contrast with England. As has been indi- 
 cated the movement really began with Hall's work on 
 the ideas of children upon school entrance which he 
 made in Boston in 1880. Several minor magazine ar- 
 ticles had appeared before this. Among these were 
 Holden's (82) study of the vocabulary of children, 
 appearing in 1877, and Humphreys (84) on the same 
 topic, published in 1880. 
 
 But these articles excited little attention. Larger 
 forces were needed to arouse the interest in child study. 
 We see how Hall had started such a movement but 
 before it attained its full force, which was not until 
 students coming under his influence as President of 
 Clark University began working in collaboration with 
 him as well as independently, another influence was at 
 work. The first work of Perez and then that of 
 Preyer were translated and made more accessible to the 
 public in general. Before the interest in these studies 
 had time to wane Shinn's "Notes on the Development 
 of a Child" (156) appeared and led to renewed in- 
 terest in individual studies. Shinn's work although the 
 first of this type of study in the United States is un- 
 doubtedly still its masterpiece, especially when her later 
 studies are considered in connection with it (157, 158). 
 
 In the meantime many minor articles had appeared, 
 but who to-day would recognize the names of Chaille 
 (27), Calkins (25), Dewey (37), Allen (2) and Tal- 
 bot (170) as authorities in this field? 
 
 From about 1890 progress seems very diff^erent. 
 
SURVEY OF CHILD STUDY 29 
 
 Baldwin's first article on right- and left-handedness (5) 
 appeared that year and was but the forerunner of his 
 "Mental Development in the Child and the Race" (6), 
 which is still a masterpiece of the followers of the 
 genetic method. Earl Barnes began writing rather 
 extensively about the same time and although educa- 
 tional in his aims he has done much to encourage child 
 study. 
 
 The Pedagogical Seminary was established by 
 Hall in 1891 and soon became almost synonymous as 
 a title with child study contributions. Its pages are 
 a history of the development of the study of the child 
 by American writers. Among those interested in this 
 subject we find Hall and his colleagues; Burnham, sug- 
 gesting especially a scheme for classification of child 
 study topics and since devoting himself more to the 
 hygiene of the child, and Chamberlain, who led afield 
 into the life of primitive peoples (28) but who has also 
 given us a most careful study "in the light of the litera- 
 ture of evolution" (29). Later we have the work of 
 Tanner (172) which pays more attention to the peda- 
 gogical significance of the various phases of child de- 
 velopment. 
 
 Among those studying under the group just men- 
 tioned and coming under their influence many have 
 made significant contributions to the study of the child 
 in its physical, moral and educational aspects, while 
 among those devoting themselves to child psychology we 
 must mention Tracy, whose "Psychology of Childhood" 
 (176) appeared in 1893, Kirkpatrick, whose work be- 
 gan in 1891 (94) and who has since given us two of 
 our best introductory texts (95, 96), Gesell (55), in- 
 terested in the young child from the educational as- 
 pect, and Patridge (127), emphasizing the study of the 
 
30 CHILD BEHAVIOR 
 
 individual. 
 
 Besides this group, originating from one center, we 
 must mention a number of other authorities, Oppen- 
 heim (1S4), Jacoby (87), King (93), Major (113) 
 and Thorndike (173). Another group follows the im- 
 pulse given by Shinn's study. Here belong the "Study 
 of a Child" by Hogan (81), Hall's "The First 500 
 Days of a Child's Life" (73) and Moore's "The Men- 
 tal Development of a Child" (119). 
 
 The practical side of the work for the child is seen 
 in Mangold's "Problems of Child Welfare" (114), 
 while an interesting sketch of the child and the history 
 of his social, political and humanitarian relations, by 
 Payne (130), has just appeared. 
 
 The present tendency in the United States more than 
 in any other country seems to be towards specializa- 
 tion of topic and method, with a great many theoreti- 
 cal as well as research contributions. The activity in 
 this country resembles more nearly that of Germany 
 than of any other country if we exclude the intense 
 interest in "tests of intelligence" which deal usually 
 with older children and wherein the French school leads. 
 
 We must not, however, think of child study as con- 
 fined to the countries mentioned. Work is evidently 
 going on in almost all civilized lands, but the differ- 
 ence in languages has made the results practically in- 
 accessible. A report by Gilbertson (56) shows that 
 the Danish Anthropological Survey has added quite a 
 little to the data regarding the weight of new-born 
 children and also concerning the so-called inferiority 
 of first-born children. Grudzinska's (67) study of 
 dolls, altho dealing largely with children of school age, 
 gives us an indication of the work being done in Po- 
 land, while her report (68) of the Child Study Asso- 
 
SURVEY OF CHILD STUDY 31 
 
 ciation of Warsaw indicates probably valuable work 
 on language, ideas of space and first esthetic impres- 
 sions. 
 
 Through Lippert (104) we find much is being done 
 in Bohemia and Moravia and he reports that many of 
 the colleges there give courses in child study. In Por- 
 tugal we find Machado (112) has made a study of his 
 child which resembles the biographical studies with- 
 which Germany and France both began. No doubt 
 other studies have been made and the fact that the in- 
 terest in child study is almost universal is seen by the 
 fact that a First American Child's Congress was held 
 in Buenos Aires in July, 1916. 
 
CHAPTER II 
 METHODS AND RESULTS OF CHILD STUDY 
 
 WE may now justly ask what are the results which 
 this child study movement has accomplished so 
 far as the psychology of the pre-school child is con- 
 cerned. The results may be grouped under several 
 heads. First there is the development of methods 
 themselves and secondly there are the facts that have 
 been determined. 
 
 The subject matter of child study may include any 
 and every thing that can be observed regarding the 
 child's development, physically, mentally, functionally. 
 The various fields of study may in general be classified 
 as: 
 
 1. Anatomical studies or those dealing entirely with 
 measurement of and description of the structure of the 
 child's body, such as measurements of height, cephalic 
 index, etc. 
 
 2. Physiological studies or those of the functioning 
 of the child's organism. The many studies of the re- 
 flexes, sleep, blood supply, digestion and motor devel- 
 opment belong here. 
 
 3. Physio-psychological or the studies of sensory de- 
 velopment and discrimination, the development of mo- 
 tor control and the early language functioning belong 
 here. 
 
 4. Purely psychological or studies of the develop- 
 ment of memory, imagination, comprehension of lan- 
 
 32 
 
RESULTS OF CHILD STUDY 33 
 
 guage and in general the expression of higher, more 
 complex forms of thought. 
 
 5. Observations of behavior or the activity of the 
 child as expressed in games, plays and spontaneous 
 occupations, often with especial regard for emotional 
 expression. 
 
 Of course two or more of these lines of observation 
 may be pursued in a single study while some studies 
 involve all five. All are interrelated and it is impossi- 
 ble to make a study, no matter how purely physiologi- 
 cal or psychological, that does not influence and at the 
 same time derive help from the other phases. 
 
 Any of these topics is a part of child psychology 
 when it is dealt with from the standpoint of the signifi- 
 cance of the factor as an indication of mental activity 
 or as a correlative of mental activity. Anatomical 
 studies may indicate growth and physiological age, 
 also functional ability. In this aspect they, although 
 they seem the most remote of any of these divisions 
 from psychology, assume great probable significance 
 if not as causative at least as correlative conditions 
 of mental growth. 
 
 The method historically first, that is the diary, indi- 
 vidual or biographical method, is the one usually 
 thought of first. The conditions for its practice are 
 the most universal — a baby, any baby, and an observer. 
 Usually the observer is one of the parents or a rela- 
 tive. The method is slow and laborious, the results 
 difficult of comparison and interpretation when ob- 
 tained. It is impossible to record every conditioning 
 factor in the environment that has led up to any re- 
 corded observation, hence the standardization of con- 
 ditions for verifying the finding upon other children 
 is impossible. The method is valuable as a basis for 
 
34 CHILD BEHAVIOR 
 
 genetic psychology and gives suggestions regarding 
 the relative appearance of various mental phenomena. 
 The work of Pestalozzi, Sigismund, Darwin, Perez, 
 Preyer, Shinn, all illustrate this method but undoubt- 
 edly the Sterns represent it at its height. A brief sum- 
 mary of their views is consequently not only fitting but 
 necessary. 
 
 Stern (162) designates the period of early childhood 
 as that of play while the period of 7-14 is that of dif- 
 ferentiation of work and play. Another difference 
 lies in the fact that the young child is under home 
 and kindergarten influences which vary greatly from 
 the school surroundings of the older child. The na- 
 ture of the young child's existence makes for observa- 
 tion of the individual over an extended period rather 
 than for the observation of a great number of children. 
 The pedagogue needs these studies of early childhood, 
 needs to know the development of the material he works 
 with. The work on the Stern children covers the first 
 six years because Stern feels the need of filling in the 
 big gap in our knowledge between what we know of the 
 first three years, studied by so many, and school age 
 which again is voluminously studied. He feels that a 
 relative, especially the mother, with psychological 
 training, is the best worker in this field and warns 
 all others not to attempt working with the child until 
 en rapport with it. He advises a study of only one 
 group of developmental phenomena when one is first 
 working in this field, but feels that the "picture will 
 be one-sided and neglect much that is important" (162, 
 p. 11). One should observe both spontaneous activi- 
 ties of the child and his reactions to stimuli purposely 
 presented. The minor importance of experimentation 
 he states very clearly. 
 
RESULTS OF CHILD STUDY 35 
 
 "It must be mentioned that for us the experiment has 
 far from the significance it has for the psychology of 
 the school child and of the adult. For as our chief 
 problem is the natural development of the child's men- 
 tal life, we must ascribe observation of natural phe- 
 nomena the chief place and avoid all which is destined 
 to artificially influence and change development itself" 
 (162, p. 12). Experiments are to be only casually in- 
 troduced side lines to verify certain points, although 
 they may be carried out on children who are not being 
 continually observed, but even here care must be taken 
 to not fatigue them. 
 
 Although in theory one can distinguish experiment 
 upon a child from observation of him under natural 
 conditions the differentiation in any one instance is 
 very difficult. The experiment in general is a presenta- 
 tion of stimuli not present normally to all or most 
 children of that age, but whether it is any more artifi- 
 cial for the son of a psychologist to play with colored 
 balls, under observation, than it is for the daughter of 
 a dressmaker to amuse herself with colored patches 
 when observed only enough to keep her from harm is 
 a metaphysical question. The fact that a child's every 
 significant act is being recorded probably means that 
 he is living in as artificial an environment when com- 
 pared with other children as would be introduced in 
 any purely experimental study. 
 
 In general we may say this method of prolonged in- 
 dividual study is the logical one for genetic psy- 
 chology; the easiest from the standpoint of obtaining 
 a subject; the slowest in obtaining results; the least 
 satisfactory for evaluation and comparison, and apt 
 to be less valuable because of its bulk and the possi- 
 bility of its becoming too much permeated with the 
 
S6 CHILD BEHAVIOR 
 
 personality of the compiler. The fact that almost 
 none save German writers seems to have thought of 
 using this method in the last decade shows that its use- 
 fulness was pathfinding, not terminal. Stern's work 
 itself is largely valuable because of the experiments 
 he adds. 
 
 A far better method, that of studying the -genetic de- 
 velopment of one type of mental activity, is the out- 
 growth of the biographical method. We see the be- 
 ginnings of this in the emphasis Heyfelder placed upon 
 language development in his study and in Preyer's espe- 
 cial attention to the development of color recognition. 
 It is along these two lines of color and language study 
 that most work of this type has been done. The mere 
 definitizing a smaller field for study makes the results 
 more definite, less voluminous and more readily studied. 
 This method may be carried out on several children at 
 the same time. In the work on language, the most 
 highly developed branch of this type of study, we have 
 no control of environment ' and hence there are great 
 uncontrolled individual variations ; such for instance 
 as the number of words in the vocabulary of children 
 of the same age studied by different observers. The 
 Sterns (163) have made this type of study on their 
 three children. The voluminous manner in which this 
 one topic is handled shows how gigantic any treatise 
 of all mental phenomena of development must be if the 
 study be as detailed and accurate. Meumann's "Die 
 Sprache des Kindes" (116) is also to be noted here 
 as it is more theoretical and gives a basis for a working 
 concept of the development of language in the child. 
 In other words, he is more successful in generalization. 
 
 A great number of purely quantitative studies of 
 the size of children's vocabularies have been made. 
 
RESULTS OF CHILD STUDY 37 
 
 Some are more, some less complete. Where the pro- 
 gress in acquisition of words has been watched to- 
 gether with a record of the total vocabulary at each 
 point we have a far more valuable quantitative and 
 genetic study. Grant (65) in his study of his son's 
 vocabulary and its growth gives a most concise, care- 
 ful treatment, using this method. The comparison with 
 other studies and the bibliography he presents are also 
 good. But in spite of the number of such studies we 
 have as yet no accepted or standard method of gath- 
 ering the data, nor have we evolved any definite stand- 
 ards of the size, rate of growth, and range of the 
 vocabulary of the so-called "average" child. We may 
 surely ascribe this to the method which renders the task 
 of gathering a great num.ber of such vocabularies an 
 impossibility for any one observer, while we lack suf- 
 ficient trained workers to have put fifty or a hundred 
 on this problem at the same time with the same 
 method. 
 
 The study of the development of color discrimina- 
 tion is far more easily pursued under experimental con- 
 ditions and it is to this subject that Baldwin early de- 
 voted his attention. In 1893 he published his sugges- 
 tions for a new method of child study, calling the 
 method by the term "dynamogenic." A full presenta- 
 tion of the method, its possibiHties and the results ob- 
 tained by the use of it were incorporated in his "Men- 
 tal Development in the Child and the Race." Al- 
 though this is chiefly an individual genetic study yet 
 experiment plays a large part in furnishing data on 
 the developmental processes discussed. Using the mo- 
 tor response or direct reflex in its simplicity he has 
 ascertained the child's reaction to a varied series of 
 situations. He recommends the use of the hand move- 
 
38 CHILD BEHAVIOR 
 
 ment as the most satisfactory and shows that through 
 it the development of relative attractiveness of two 
 stimuli; relative attractiveness (or better, stimulative 
 ability) of two colors, two forms, or two brightnesses ; 
 the relative use of right and left hands; the develop- 
 ment of imitative, voluntary and ancillary movements, 
 as well as accuracy of estimation of distance may be 
 studied. The method is used by the author to stud}^ 
 color preference and the development of right- and left- 
 handedness. 
 
 The interest of the author is, however, not centered 
 in the experiments as such but he writes, "On the whole, 
 therefore, I attach very little importance to the ex- 
 periments apart from their illustrative value and their 
 possibly stimulating effect upon others who may care 
 to extend them. For these latter reasons, however, as 
 much as for the positive inferences I have drawn from 
 the above, I have felt that they ought not to be un- 
 recorded. Their main purpose in the progress and 
 plan of this book is seen in their witness to the regu- 
 larity of operation of the principle of suggestion or 
 dynamogenesis" (6, p. 57). 
 
 This method stimulated greatly the work on color 
 discrimination and also that on the rise of right- or 
 left-handedness. Results may be seen in the studies 
 of McDougall and Valentine, already mentioned, as 
 well as in those of Katz (92), but we must not forget 
 that the work of Garbini on this subject is far more 
 extensive and thorough, although he studied the evolu- 
 tion of the color sense by experimenting upon a num- 
 ber of children at different ages in preference to con- 
 fining himself wholly to following its development in a 
 smaller number of children. 
 
 The method of retrospection, or the use of autobiog- 
 
RESULTS OF CHILD STUDY 39 
 
 raphies is far less satisfactory. The adult looks back 
 upon his early childhood as an idealized experience. 
 His attitudes,^ understanding, ideals are so different it 
 would be impossible for him to give us a true picture 
 of the child's attitude and ideals and thoughts. Such 
 books as those of Una Hunt (85) and Pierre Loti 
 (110) may give us a real insight into how adults re- 
 gard their acts as children but they are not child na- 
 ture naive and simple. The work of Folsom (48) al- 
 though dealing with a later period of child life is a 
 suggestion which may lead to better things. The day- 
 book kept by his mother and the records in his own 
 writings give a basis of fact from which it is not so 
 easy to stray. If we could have a biographical study 
 of a child and then later his independent and sponta- 
 neous autobiography, if this might be done in only one 
 instance, the relative value of the autobiography might 
 be more readily estimated, but even then the proba- 
 bilities are that its value would be for adult rather than 
 child psychology, and would connect this method with 
 another already in use, that of psycho-analysis. 
 
 Psycho-analysis is not, properly speaking, a child 
 study method but again a method secondarily con- 
 cerned with the things that have impressed the child 
 and primarily a method of investigating the undue per- 
 sistence in the adult of unfortunately conditioned as- 
 sociations and their emotional concomitants. By it we 
 can trace the complex functionings of the adult back to 
 infantile states but we cannot foretell in similar detail 
 the development of such states in the child. 
 
 The methods mentioned so far are largely individual 
 in their application, but there are several others which 
 are distinctly applicable to a more or less extensive 
 group. Of these the questionnaire or statistical method 
 
40 CHILD BEHAVIOR 
 
 has been the most widely used and with the most varied 
 value in the results. Its characteristics fit it for a 
 special type of study. The observations may reach 
 into the tens of thousands, and come from a widely 
 distributed group of observers. These are both ad- 
 vantages but precautions must be observed in its usage 
 or there will be disadvantages also. Unless the ques- 
 tions are clear and specific the answers are apt to be 
 less pertinent and hence less valuable. The question- 
 naire should not be too long or the demand upon the 
 observer's good-will will outlast his attention. The 
 evaluation of the results must allow for the use of an 
 indirect method and not stress the importance of minor 
 differences. Keeping these points well in mind the 
 method has certain very specific values. Hall has used 
 it with especial success to gather data regarding those 
 forms of individual experience which can not easily 
 be experimented upon in the laboratory. Especially 
 significant is his work on fear (72). It is to the 
 broad vision given by such studies that his volumes 
 on adolescence owe much of their seer-like qualities. 
 This method is also less apt to be unreliable if the data 
 gathered are objective results such as children's draw- 
 ings or if they have a numerical basis such as would 
 be involved in a study of height, weight or counting 
 ability. 
 
 Another method is the study of only one or two 
 mental processes in a large number of children. If 
 we contrast this with the biographical method we see 
 that they stand at right angles to each other. The bio- 
 graphical method follows the child as he ascends in 
 experience. The quantitative method takes any one 
 point in his ascent, cross-sections it and studies its con- 
 dition not only in the exceptional children but in all 
 
RESULTS OF CHILD STUDY 41 
 
 children. One of the first pieces of work done in this 
 way was that of Binet (13) on line comparison and 
 number perception. This was done in 1890. Although 
 his methods are very crude and the study was made 
 only upon his two daughters then 32 and 52 months 
 of age it is a beginning of his work which leads to two 
 types of study, to a purely scientific study of the men- 
 tal processes of young children, on one hand, and, on 
 the other, to a standardization of processes possible 
 at definite ages in order to estimate the relation of any 
 one child's ability to that of the group for his age. 
 These are the so-called "tests of intelligence." These 
 two lines are really one and the same type of study. 
 Any process that has been so thoroughly and volumi- 
 nously studied that we know what ability in that line 
 to expect of a child of any given age is a "standard- 
 ized" process. Henceforth trying it out upon any 
 given child is merely ascertaining his relation to the 
 rest of the group, or in other words it is a "test." It 
 will at once be seen, however, that this is true only 
 under certain conditions, namely, if the original study 
 has been made under controlled conditions which may 
 be exactly reproduced when our individual child is 
 tested. Such a method complies with the demands of 
 experimental psychology and its use as a test fulfills 
 the demands of applied, especially clinical, psychology. 
 
 Many studies have combined two or more of these 
 methods such as biography and slight experimentation, 
 biography with statistical and comparative confirma- 
 tion, questionnaire and observation, developmental and 
 group experiments. The results are of varied signifi- 
 cance. 
 
 If we were to attempt the formulation of a textbook 
 of the psychology of the first five or six years of life 
 
4S CHILD BEHAVIOR 
 
 on the same general plan as we would formulate a text 
 on adult psychology we should find some phases so un- 
 touched by child study tliat all we could do would be 
 to state our ignorance. In other phases the accumu- 
 lated facts are so multitudinous that they would form 
 whole books in themselves. This is not all due to the 
 developmental and evolutionary character of child 
 study material but also to the factors which largely 
 influenced its development. Before evolution as a 
 theory was advanced, there could be little need of 
 studying the evolution of the child's mind more than 
 just enough to determine when his "faculties" were suf- 
 ficiently developed to make education possible and 
 probable. Nor could experimental methods be used 
 until experimental psychology had become a fact. Con- 
 sequently the earliest work in child study was either 
 the observation of his development for the purpose of 
 founding on such evidence sound educational princi- 
 ples, as was the avowed purpose of Tiedemann and 
 Froebel, or due to the purely scientific interest of a 
 group of men not dependent upon psychological meth- 
 ods. This is the group with medical training, Lobisch, 
 Sigismund, Kussmaul. They used the physiological 
 method and although an exact knowledge of the time 
 at which a child begins to show that he hears sounds 
 or perceives light is less necessary for medical practice 
 than for educating the child, the purely scientific in- 
 terest in the child developed along these lines just be- 
 cause there was a method by which these phenomena 
 could be studied while the avenues of approach to men- 
 tal processes themselves seemed closed or lacking. 
 
 Consequently the studies on the development of the 
 senses have been numerous and persist as a favorite 
 subject for investigation in physiological psychology 
 
RESULTS OF CHILD STUDY 43 
 
 to-day, although the method used has gradually passed 
 from individual observation to a statistical, experi- 
 mental procedure. This is easily seen if we compare 
 the work of Kussmaul with the study by Peterson and 
 Rainey (135), in which they studied 1060 children 
 born in the same hospital and kept under the same 
 conditions for the first few days of life. Various com- 
 pilations of these findings have been made such as those 
 found in the work of Tracy (176), Chamberlain (29), 
 Cramaussel (33), Gaupp (53) and Tanner (171). 
 
 Besides sensory development many observations have 
 been made upon the motor development of the child. 
 Here again we must rely largely upon the individual 
 studies. The age at which the child holds its head 
 erect, sits, creeps, stands, walks, the appearance of 
 tactual and distance prehension have all been minutely 
 recorded by Sigismund, Preyer, Shinn and others. 
 Some work on the standardization of the time at which 
 these develop was done by Binet and Simon (16) in 
 1904. 
 
 The work of Dearborn (35) should be mentioned 
 here. It is the study of a child's development but not 
 made in the same manner as the other individual studies. 
 The author keeps an objective attitude and, focusing 
 especially upon the child's motor and sensory activities, 
 records them day by day, keeping his comments differ- 
 entiated from the actual observations. The arrange- 
 ment and method give the book significant value as a 
 modem scientific contribution and indicate many de- 
 velopmental features that should be investigated by the 
 statistical method. 
 
 The data on memory is to be found chiefly in the 
 pages of the biographical or individual studies which 
 record the spontaneous utterance of recalled situations 
 
44 CHILD BEHAVIOR 
 
 and the recognition of persons and places known at an 
 earlier period. Lately, however, we have the adoption 
 of an experimental method and an already valuable 
 literature on memory as studied through the Aussage 
 method. We must note especially the work of Stern 
 (161, 164), while the workers with mental tests de- 
 pend perhaps too much upon the use of this method 
 and the method of immediate recall because of develop- 
 ment of norms of memory span for auditory presenta- 
 tion of digits, sentences, etc. 
 
 Correlated with this work on the Aussage we should 
 mention that of Binet (14, 15) which gives the basis 
 for Stern's work although it deals largely with older 
 children. 
 
 Winch (186) made a widely extended study of ob- 
 servation and report upon English school children but 
 includes infant schools, and, consequently, children 
 from three to seven years of age. These were picked 
 to represent bright, average and dull children, in all 
 giving ten of each at each age. The three-year-old 
 children could not correct their first Aussage con- 
 cerning the picture but older ones could. The power 
 of reporting grew more rapidly than the power of ob- 
 servation while the demand for production and repro- 
 duction of what was seen when the picture was origi- 
 nally shown did not improve the memory of it but ren- 
 dered it more imperfect. The improvement in report 
 is a steady one from the age of three up to seven but 
 less regular above that. 
 
 The study of Ballard (7) on memory and forgetting 
 touches only the upper end of this period. The young- 
 est children he studied were five years old. He used 
 simple verse and tested the amount they recalled and 
 the improvement in learning. He found that younger 
 
RESULTS OF CHILD STUDY 45 
 
 children improved more, and more rapidly, than older 
 children but his results are open to some criticism as 
 he used more difficult material and sometimes a differ- 
 ent mode of presentation with older children. 
 
 Kammel (90) tries to make use of retrospection, un- 
 der partially controlled conditions. He saw the sub- 
 jects himself and explained his desire to them having 
 them write their earliest remembrance. After three 
 months he saw them again and asked for a report of 
 any earlier memories. Out of 344 pupils from 12 to 
 20 years of age only four remembered any earlier event 
 and only 16 changed minor details of the former rec- 
 ord. He feels this method is better than the ques- 
 tionnaire method used by Miles (118), Henri (77) and 
 others. The results are not very enlightening from 
 the standpoint of child psychology. The earliest mem- 
 ory is most apt to come from the fourth year of life, 
 although some come from as early a period as the 
 second year. The fact remembered by the child is 
 more apt to be aroused by some external situation than 
 by his own person and is apt to be preserved in visual 
 imagery and have a strong emotional background. 
 
 Another line of study, that of language develop- 
 ment, is also one not needing very intricate methods 
 but simply careful observation. Consequently the rise 
 of this part of child psychology has also been inde- 
 pendent of the development of modern methods. 
 Through the study of language development not only 
 is the acquisition of voluntary control of the vocal or- 
 gans to be observed, but the psychologist reads into it 
 and studies through it the beginnings of learning or 
 formation of associations. The child first learns to 
 associate the spoken word with the object or action. 
 Then as he learns to say the word he applies it to the 
 
46 . CHILD BEHAVIOR 
 
 object himself and gradually develops the ability to 
 use groups of words. Whether his understanding of 
 situations grows as his use of language grows is a 
 matter of speculation. The objective evidence of lan- 
 guage is in itself valuable for the genetic and compara- 
 tive psychologist and also for the student of anthro- 
 pology and sociology but it tells us little of the po- 
 tentiality of the mind behind the expressions. Such 
 great individual and group variations are found, proba- 
 bly due partly to environmental conditions, that the 
 study of the language development is difficult enough 
 without complicating it by attempting too many infer- 
 ences regarding the conditions of its development. 
 
 Most of the language studies deal with its develop- 
 ment through the first three years of life. The size of 
 vocabulary and consequent increase in complexity of its 
 usage make any complete study above that age rather 
 difficult. There are some studies that deal with one 
 phase or another of speech of the period from three 
 to six but nothing complete enough to bridge the gap 
 entirely. With the older children, especially those just 
 entering school, other cross-sectioning methods are 
 used. These are usually verbal association methods 
 or the methods of definition and explanation of a list 
 of words such as were used by Lange, Hall, Netschajeff 
 and others in studying the contents of children's minds. 
 The method, consequently, does not give direct infor- 
 mation regarding language usage itself but rather re- 
 garding the comprehension of it and the studies have 
 been largely pedagogical in their purpose. Pohlmann's 
 (138) work is the best example of the application of 
 this method, extending its usage on children of all 
 ages up to fourteen. His work touches the fore-school 
 period as it includes a study of six five- and six-year- 
 
RESULTS OF CHILD STUDY 47 
 
 old children. This number, however, is small and he 
 reports such a large percentage of admissions of igno- 
 rance of the words or refusals to answer that one 
 doubts whether his method was applied with sufficient 
 admixture of understanding of these younger children. 
 
 One other study, that of Engelsperger and Ziegler 
 (43) should be mentioned here. Motivated by the 
 studies on children entering school, they attempted a 
 more scientific and exact study of not only the mental 
 but physical development in a group of nearly 500 
 children just beginning school work. The psychologi- 
 cal study, although confined to the development of the 
 color sense, is very detailed. Color perception, match- 
 ing and naming were studied and significant indica- 
 tions of the narrowness of range of discrimination were 
 found. Interesting sex differences are also indicated 
 by their tables, but so far as mental processes go we 
 know but little more than we did before. The study 
 is one of knowledge acquired, not of processes. 
 
 Aside from the work on memory and language and 
 the study of the learning process thus involved very 
 little attention has been paid to the process of acquisi- 
 tion itself. There is no literature available upon which 
 to base a discussion of the learning process of the in- 
 fant which would be similar to and supplement that of 
 Meumann (117) on school children and adults. 
 
 The only other subject widely investigated which 
 might be said to belong to child psychology is that of 
 the activities of children, their games, arts and occu- 
 pations. Few of these are subject to experimental 
 control but we have an advantage in studying one form 
 of activity which is objective in its results — this is 
 drawing. A great deal has been done with the study 
 of spontaneous productions of copies of objects and 
 
48 CHILD BEHAVIOR 
 
 of illustrations of stories. The studies of Ricci (144), 
 Elmer Brown (20) and Barnes (8) are all valuable 
 although they deal less with the children under school 
 age than with those of school age. They do give us 
 some idea of the things present in the child's concept, 
 say of a man or a chair, but tell us little of how he 
 develops that concept. 
 
 Even such a brief survey of the field convinces one 
 that the number of studies made upon the mind of the 
 pre-school child by the methods of experimental psy- 
 chology are few. Why is this all psychology has had 
 to offer here.? There are at least three definite reasons. 
 
 The investigation of the child mind was first moti- 
 vated by a desire to gather in this field facts that would 
 help pedagogues. This aim naturally limited the ma- 
 jority of studies to children of school age, although 
 the importance of a knowledge of the child of pre- 
 school age has often been emphasized but even when 
 so emphasized the attitude is not purely scientific and 
 has been beautifully described by Burnham, who writes 
 "The prime motive for such study has generally been 
 the training of teachers in the observation of children. 
 It has been done directly for the sake of the teachers ; 
 indirectly for the sake of the child, and incidentall}'^ 
 for the sake of science" (23, p. 198). 
 
 Another factor is the difficulty of securing any con- 
 siderable number of young children who will form a 
 rather unselected group. This is evidenced by the lack 
 of extended studies upon the periods between earliest 
 infancy, where babies are available in maternity hos- 
 pitals, and the kindergarten school age which again 
 brings them together in a social group. The child 
 of two, three or four lives in the home, not in a large 
 group of his kind. Hence each must be sought alone. 
 
RESULTS OF CHILD STUDY 49 
 
 The rise of interest in evolution has also tended to 
 strengthen the natural conditions which make for the 
 study of the individual. 
 
 But the most important reasons for neglect of scien- 
 tific studies of mind in this period lie in experimental 
 psychology itself. Experimental psychology is com- 
 paratively new, it is still in many fields working out 
 more satisfactory details of procedure and apparatus 
 for its adult subjects. The methods have evolved 
 around introspection and are such as necessitate it 
 as a part of the procedure. This at once makes it dif- 
 ficult for the psychologist studying the adult to see 
 how the infant could be experimented upon since he 
 surely can not introspect; although a species of report 
 may be obtained from his older brothers or sisters. 
 Ament, for instance, says that we can not experiment 
 upon the young child with full satisfaction because the 
 child is a growing person and the use of many experi- 
 ments depends upon the development of the processes 
 to be studied, while, he writes, "The possibility of ex- 
 perimenting with the child develops as the child de- 
 velops" (B, p. 100). Only as the child approximates 
 the mental equipment of the adult can we hope to study 
 him in a similar manner. 
 
 Chrisman advised laboratory study of the child of 
 three years or under in his dissertation in 1896. He 
 notes the need of not over-fatiguing the child and in- 
 sists that "no experiment dare be unpleasant or the 
 least bit harmful" (31, p. 42), but when he comes to 
 outline the work that is to be done in the laboratory he 
 gives the directions for an elaborate anthropometric 
 study and then confines his directions for mental ob- 
 servation to sensory discrimination, especially of color. 
 
 Peper (131), too, approves of the use of experi- 
 
50 CHILD BEHAVIOR 
 
 ments but in his attempt to give a list of experiments 
 to be tried we find he mentions all those which are 
 usually used upon older subjects and he gives no sug- 
 gestions for modifications to be made for use upon 
 younger children. 
 
 Groos (66) rather discourages any attempt at ob- 
 servation under controlled conditions because of the 
 difficulty of simplifying our methods. He feels that if, 
 however, we can apply an experimental method and at 
 the same time keep the child entirely ignorant of our 
 purpose it is the best plan to pursue. 
 
 Wundt represents fairly well the attitude experi- 
 mental psychologists have held when he says "Animal 
 and child psychology are relatively of less value when 
 compared with the physiological disciplines of human 
 and comparative history of development" (187, p. 6). 
 But Stumpf (165) takes a more optimistic view and 
 points out that although we can study the child only 
 through his reactions to external and internal stimuli, 
 yet this indirect method is probably balanced by the 
 fact that the child shows his reactions with less dis- 
 sembling and control than the adult. 
 
 Ufer, too, relies mainly upon prolonged observa- 
 tion of the individual although he does state that "Ob- 
 servation under experimental conditions also has its 
 justification" (177, p. 70). 
 
 However, it is not until we come to the work of Katz 
 that we find an ardent champion of the use of the 
 scientific method in studying young children. 
 
 Katz points out in answer to Ament's statement of 
 the impossibility of studying the child that "the pos- 
 sibility of experimenting with the child decreases with 
 the development of the child" (92, p. 21). He points 
 out that the mere fact that a young child cannot in- 
 
RESULTS OF CHILD STUDY 51 
 
 trospect in itself constitutes a problem worth investi- 
 gating while the impossibility of using the introspec- 
 tive method should not be thought to be synonymous, 
 as it has been by Ament and many others, with the 
 impossibility of studying the child by a method built 
 up with especial regard for the child characteristics. 
 
 Katz feels that he has a method which is an infant 
 psychology method and which will bring results which 
 we can get in no other way, and he applies the ex- 
 perimental method in the study of the origin of color, 
 form and size concepts and hence of abstraction. He 
 used S9 children between the ages of two and a half and 
 six and a half years of age and found no difficulty in 
 keeping the children interested and happy. 
 
 If we wish to know how he first conceived the idea 
 of using the experimental method with children we can 
 find the answer in his earlier study with Revesz (91). 
 This was originally a study of the memory and learn- 
 ing of hens but in the interests of comparison they 
 made a study of twelve children between the ages of 
 one and a half and five years of age, using the same 
 method, only substituting play counters of different 
 colors for the different kinds of grain given the chick- 
 ens. They also used a verbal Aufgabe but felt that 
 the children, especially the younger ones, comprehend- 
 ed the situation more through the environmental con- 
 ditions than through the actual verbal directions. 
 
 This leads us to ask whether the adoption of the 
 methods of animal psychology is unique with Katz or 
 whether others have made similar usage of it. The 
 attempts so far are not numerous but they represent 
 a new endeavor to reach a scientific method of studying 
 the child and are consequently worth surveying. 
 
 Any usage of the child under methods of study 
 
52 CHILD BEHAVIOR 
 
 which approximate those of comparative psychology 
 will not be handicapped by lack of knowledge of the 
 mental processes of the child but will deal primarily 
 with his behavior or his objective reaction to definite 
 stimuli presented in a definite manner under controlled 
 conditions. How much have the methods of behavior- 
 ism or objective psychology so far contributed to our 
 knowledge of the child ? 
 
CHAPTER III 
 BEHAVIORISM AND CHILD PSYCHOLOGY 
 
 THE study of behavior has come to mean the study 
 of any of the visible and external movements of 
 the organism, whether man or the lower animals be the 
 object of study. The explanation of the movements 
 studied is made as far as possible in purely objective 
 terms and subjective interpretations are carefully 
 avoided. Animal psychology, since its development 
 from the anecdotal stage, depends almost entirely upon 
 this method but the study of behavior is not purely 
 psychological. As Parmelee (126) points out the 
 study of behavior involves the study of anatomical 
 structure and physiological processes and is conse- 
 quently fundamentally biological, while it is psychologi- 
 cal when mental processes are involved and sociological 
 when the behavior is influenced by association with 
 other human beings. 
 
 The confusion of this distinction disappears, how- 
 ever, if we assume another point of view. Psychology 
 is in reality only a part of the larger science of life in 
 general which we call biology and hence assumes as its 
 basis the presence of structure and physiological 
 processes in the organism. Social reactions it does not 
 consider as other than reactions to living stimuli and 
 so essentially the same in process as the reactions to 
 inanimate objects. This attitude is that adopted by 
 present-day comparative psychologists and is well ex- 
 
 53 
 
54 CHILD BEHAVIOR 
 
 pressed by Watson (184) in his book on behavior. 
 
 Although written primarily as an introduction to 
 comparative psychology Watson's book is not limited 
 to the field implied by such an aim. In it he touches 
 upon and takes a definite attitude towards many ques- 
 tions that will probably remain as bones of contention 
 for many years. He writes, "Psychology, as the be- 
 haviorist views it, is a purely objective, experimental 
 branch of natural science which needs introspection 
 as little as do the sciences of chemistry and physics." 
 The theoretical goal of behavioristic psychology is "the 
 prediction and control of behavior" (p. 1). This 
 shows at once the field of study the behaviorist pre- 
 empts. The adjustments of the organism, whether 
 it be amoeba or man, will be observed and correlated 
 with the potent stimuli under conditions which make it 
 possible for the results to be verified. Although hop- 
 ing for concessions on the part of the experimental in- 
 trospectionists so that the work from the two view- 
 points may be mutually helpful, yet these are not be- 
 ing taken for granted and Watson writes, "Should hu- 
 man psychologists fail to look with favor upon our 
 overtures and refuse to modify their position, the be- 
 haviorists will be driven to use human beings as subjects 
 and employ methods of investigation which are exactly 
 comparable to those now employed in the animal 
 work" (p. 3). 
 
 The behaviorist looks upon the organism as a ma- 
 chine and only insists that in concept this "machine 
 be not too simple to enable it to perform all the multi- 
 tudinous demands which the behaviorist must make 
 upon it" (p. 52). The organism, under study, is char- 
 acterized by two types of behavior, instinct and habit. 
 Both of these are made up of reflexes. The neural 
 
BEHAVIORISM AND CHILD PSYCHOLOGY 55 
 
 basis of these reflexes is inherited and "It is probable, 
 furthermore, that at the birth of the animal or soon 
 afterwards all possible nervous connections are already 
 established and that all later development — all adjust- 
 ments of the animal to changes in its environment by 
 habit formation involve only changes in resistance 
 through various inherited areas. Thus the possible 
 habits which an organism may acquire are limited by its 
 nervous structures" (p. 151). 
 
 "Reflex, then, as a unit of analysis of instinct (as 
 also of habit . . .) in the modified sense in which 
 we use the term, embraces (1) the fairly definite and 
 generally predictable but unlearned responses of lower 
 and higher organisms to stimuli . . . We must be care- 
 ful . . . not to overemphasize the concept of invaria- 
 bility and predictability, since depending upon the 
 physiological state of the organisms we find, in ex- 
 treme cases, the situation where a stimulus which at one 
 time produces positive response may, under other con- 
 ditions produce negative response ... (2) We have 
 in the case of both vetebrates and invertebrates many 
 cases of highly unstable and indefinite response" (p. 
 110). 
 
 Habit may be diff^erentiated from the instinct in that 
 the group of reflexes which form it are organized into 
 the order (or temporal order of the unfolding of the ele- 
 ments) and pattern (or number and localization of the 
 simple reflex arcs involved) within the life period of 
 the individual. "What is new in habit is the organi- 
 zation. The elements, in general, are as old, or as 
 new as the race" (p. 109). 
 
 The "present end of analysis, then, in behavior will 
 be the reduction of complex form of response to simple 
 reflexes." In many phases the analysis must for the 
 
56 CHILD BEHAVIOR 
 
 time be but partial as both the extra- and the intra- 
 organic stimulations function in the determination of 
 the observable response and in many cases the intra- 
 organic stimulation cannot be accurately determined. 
 
 Yerkes holds a similar view and writes : "Human be- 
 havior is only a part, albeit a most important part, of 
 the materials of the general science of organic behavior. 
 It presents essentially the same kinds of problems as 
 does the behavior of any other mammal ; and it must be 
 studied by methods similar to, if not actually identical 
 with, those emphasized by the student of infra-human 
 behavior" (189, p. 625). 
 
 Only a very few studies of children have been made 
 by psychologists holding such a view of psychology as 
 behavior. They are consequently worth noting indi- 
 vidually. 
 
 In 1911, Hamilton reported a study made for the 
 sake of comparing the reactions of various mammals. 
 He used a method of quadruple choice. Four possible 
 exits from a confining chamber led to food and escape. 
 All doors but one were closed and the one opened varied 
 from trial to trial. The task was to find the correct 
 exit, and hence food, with the smallest number of un- 
 successful attempts. Various mammals, cats, dogs, a 
 horse, were used as well as a normal adult, children and 
 several defectives. All but one of these, an infant of 
 26 months, were of school age or over. The infant was 
 stimulated with toys when "commendation proved insuf- 
 ficient as a motive for reaction" (74, p. 38). This child 
 is reported as walking, talking, but not in sentences, 
 and as being very quick to form new associations. 
 
 If the child had tried each door once until he found 
 the correct one the number of trials he would have 
 needed for success due to pure chance would have been 
 
BEHAVIORISM AND CHILD PSYCHOLOGY 57 
 
 250 for the 100 successes required. As it happened he 
 used 315 trials and many of his trials (34.21%) 
 were re-trials of the same door and hence non-selective 
 in character. 
 
 The study is interesting although less valuable be- 
 cause made on only one individual in early childhood 
 but fails to give us any statement of the exact verbal 
 and objective stimuli used. 
 
 Yerkes uses a multiple choice method which is some- 
 what similar to the quadruple choice of Hamilton but 
 more variable. He says, "The method has been em- 
 ployed in experiments with normal and defective chil- 
 dren, normal and insane adults, pigs, rats, crows and 
 ring doves" (192, p. 186). 
 
 So far however only the results upon crows, pigs and 
 monkeys have been published. That it is a satisfactory 
 method for working with human beings seems evident 
 from a statement in his recent publication on its use 
 with monkeys. He writes : "The method has been ap- 
 plied with most gratifying results to the study of the 
 characteristics of ideational behavior in human defec- 
 tives — children, and adults — and in subjects afflicted 
 with various forms of mental disease" (188, p. 9). 
 
 In the same manuscript he reports the behavior of a 
 child forty months old as compared with that of an 
 orang-utan. A banana was suspended from a string 
 at a point too high to be reached unless 2 boxes were 
 stacked and then stood upon. The child was asked to 
 get the banana for the orang and made a number of 
 attempts to reach it interspersing them with play and 
 interest in other objects and finally losing all inter- 
 est so that the experiment was discontinued after 55 
 minutes. The orang showed great concentration of 
 attention and Yerkes contrasts his behavior favor- 
 
58 CHILD BEHAVIOR 
 
 ably with that of the child. Any comparison, how- 
 ever, seems rather arbitrary when we recall the con- 
 ditions. The orang was striving for food, the thing 
 he understood best, and the stimuli from the situa- 
 tion would be reinforced by habit and any hunger sen- 
 sations. The child was given a verbal Aufgabe and 
 the interest aroused in the banana was not the ego- 
 centric one of self-acquisition and self-satisfaction but 
 an appeal to his sympathy for the orang. The sit- 
 uations are very different and the results naturally are 
 not alike in the two instances. 
 
 The maze has been used with human subjects but no 
 one has tried it on very young subjects. Hicks and 
 Carr (80) used it upon children as young as eight 
 years of age but below this age we find no records al- 
 though the method is probably applicable if care be 
 taken to increase the complexity of the situation gradu- 
 ally. There should be no difficulty about using the 
 method without a direct verbal Aufgabe. 
 
 Hunter (86) used the method of delayed reactions 
 upon raccoons, rats, dogs and children. There were 
 five children in all, one two and a half years old, three 
 six years of age and one eight years old. The method 
 with the children differed radically from that used with 
 the animals, the play attitude was suggested and the 
 verbal Aufgabe given. The task was as follows : The 
 child was behind a gate with the experimenter. On the 
 opposite side of the room were three buttons which when 
 pushed might make a noise or not as the experimenter 
 desired. Above the buttons were electric lights. The 
 child was told and taught through accommodating 
 practice that if he pushed the proper button it would 
 buzz and if he pushed this noisy button first he would 
 get some candy. Then the light over some one button 
 
BEHAVIORISM AND CHILD PSYCHOLOGY 59 
 
 was switched on and off, the child was detained a num- 
 ber of seconds, varying in the different trials, and then 
 allowed to press the button. During the delay inter- 
 val, which sometimes lasted twenty minutes or more, 
 the child talked to or exchanged stories with the experi- 
 menter, drew pictures and in some cases of long delay 
 was given candy. 
 
 The children had to acquire the association of the 
 light and button for themselves and develop some 
 method of retaining this associated factor during the 
 delay period in any one trial. All save the youngest 
 child learned the association in one trial. With her 
 no errors were made after the seventeenth trial. In the 
 delayed reactions two children who were six years of 
 age experienced no difficulty until the interval had 
 lengthened to more than four minutes. These two for- 
 mulated their own "purpose to remember." The third 
 six-year-old child was told the purpose of the experi- 
 ments and had only one error in 15 trials, that on a 21- 
 minute interval, although he succeeded on a 35-minute 
 interval. This shows clearly the help given by the for- 
 mulation. The two-and-a-half-year-old had great diffi- 
 culty with even the 10 second period, failing 30% of the 
 time although she did far better than that on periods 
 as long as 50 seconds. These failures on the shorter in- 
 tervals probably represent her failures to formulate a 
 successful method of remembering. 
 
 The children are reported as being impatient and 
 as fretting because of the delay although this unpleas- 
 antness was reduced and largely eliminated by the dis- 
 tractions during the delay period. The memory cue as 
 to which button to press did not seem to depend at all 
 upon a distinctive motor attitude but is due. Hunter 
 thinks, to some intra-organic cue which does not persist, 
 
60 CHILD BEHAVIOR 
 
 due to the distractions during the delay period, but is 
 revived at the moment of release. Whether this revived 
 cue is sensory-perception or imaginal in content re- 
 mains doubtful. 
 
 This is all that has been done with behavior meth- 
 ods in the study of young children. The results are 
 rather discouraging in a way but are only what might 
 be expected when they are the attempts of workers 
 primarily interested in animal psychology. They 
 make rather good usage of play and rewards but none 
 seems to have been able to regard the child in a purely 
 objective way as an animal with as distinctive charac- 
 teristics as any other animal. Hamilton uses food as 
 an incentive for his animals but substitutes toys with 
 the infant. Katz substitutes the still more remotely 
 affective stimulus of colored counters. Yerkes makes 
 a similar error and all three introduce with children 
 the additional factor of language. Hunter's work is 
 better in his handling of the child but it, too, depends 
 upon language development, while all the methods are 
 cumbersome and unwieldy, and the results, so far, are 
 vague, indefinite and complex. 
 
 But a more exact method of studying the less obvious 
 behavior reactions of animals has been developed by 
 another school. That is, by the group of Russian 
 physiologists led by Pavlov. Their methods and re- 
 sults are less easily accessible and hence less well known 
 in this country. What have they accomplished that 
 may be utilized in the study of behavior? 
 
 In 1863 there appeared in the Russian tongue a work 
 entitled "The Reflexes of the Cerebrum." The author, 
 Setchenov, was far in advance of his time. He saw 
 psychology as a part of physiology, saw it using the 
 methods of the natural sciences and concentrating 
 
BEHAVIORISM AND CHILD PSYCHOLOGY 61 
 
 upon the study of motor activity. Although his the- 
 ories were somewhat crude, and not wholly in accord 
 with the views of Helmholtz which were then generally 
 known and accepted, they are most valuable. He for- 
 mulated the theoretical basis of the Pavlov method of 
 to-day. 
 
 "The psychical processes of man," he writes, "are, as 
 is known, recognizable through outer phenomena, and 
 usually the laity, as well as the naturalist and the 
 psychologist, form an opinion of them by that means. 
 Every one knows how great the world of these phe- 
 nomena is. In this world are included the great variety 
 of movements and sounds of which man is generally 
 capable. And this whole mass of facts must be compre- 
 hended as far as possible and nothing left unconsidered. 
 The problem at the first glance seems insoluble, but in 
 reality it is not, and the reason it is not is as follows : 
 The whole endless multiplicity of the outer manifesta- 
 tions of cerebral activity may be reduced to a single 
 phenomenon, that of muscular activity. Thereby this 
 question is considerably simplified. In reality it so hap- 
 pens that a milliard phenomena, which apparently have 
 no connection with one another, may be traced back to 
 the activity of a single group of muscles. We know 
 that under the hand of the musician impassioned and 
 mournful tones may be charmed from the lifeless in- 
 strument. The animating and creative hand of the mu- 
 sician and the sculptor execute in reality only a num- 
 ber of purely mechanical movements which, critically 
 examined, may even be submitted to a mathematical 
 analysis and be expressed by a formula. How would 
 they be able under such conditions to impart the ex- 
 pression of passionate feeling to tones and pictures if 
 it were not a purely mechanical act.'' There will surely 
 
62 CHILD BEHAVIOR 
 
 come a time when the outer manifestations of cerebral 
 activity will be subjected to analysis just as the physi- 
 cist analyses musical accord or the phenomena which 
 are manifested by a freely falling body" (153, p. 3). In 
 another place he writes: "Thought is the first two- 
 thirds of a cerebral reflex" (154, p. 135). 
 
 The work of Setchenov was pioneer but it remained 
 for Pavlov and his followers to work out through labor- 
 ious experiments the first exact confirmation of his 
 theories. 
 
 Under Ivan P. Pavlov, as Director, the work of all 
 in the Physiological Department of the Institute of Ex- 
 perimental Medicine of St. Petersburg, was for many 
 years concentrated on the study of the digestive glands. 
 The first considerable announcement of the results ap- 
 peared in the year 1897, in the book, published by Pav- 
 lov himself, entitled "The Work of the Digestive 
 Glands." An English translation of this book was not 
 made until 1902. In the preface of it Pavlov states 
 that the book is "a joint work, the result of the princi- 
 ple, which actuates the whole laboratory. It owes its 
 existence to the acuity of each individual, but in its to- 
 tality to the guiding conception which has inspired us 
 all" (129, p. xi). With the exception of several short 
 reports this is the only statement of the work of the 
 Russian school accessible in English. A brief resume 
 of their problems and results is therefore permissible. 
 
 The subject matter has been tlie physiology of the 
 digestive glands. The reason for taking up this sub- 
 ject is, Pavlov states, a desire to replace the older, er- 
 roneous views presented in textbooks by a fuller and 
 more correct representation of the work of these glands. 
 The earlier work was based upon the secretion of the 
 salivary and gastric glands, or thei galivary and gastfic 
 
BEHAVIORISM AND CHILD PSYCHOLOGY 63 
 
 reflexes, as they were called. The method consisted in 
 the study of the quantitative and qualitative modifica- 
 tions of the reflex which were conditioned by complex 
 receptive and elaborative processes (psychic reactions) 
 in the central nervous system. As Pavlov stated, 
 "Natural science is under an obligation to determine 
 only the precise connection which exists between the 
 given natural phenomena and the responsive faculty of 
 the living organism with respect to this phenomenon" 
 (128, pp. 613-614). 
 
 The technique, involving, as it does, delicate and ac- 
 curate surgical methods, is in itself a triumph and too 
 well-known to need description. It will suffice to recall 
 that from an artificial opening, drawing ofi^ from its 
 natural function whatever secretion is being studied, 
 there extends a small canula and tube by which the 
 drops are either counted as they fall, or are measured 
 by the scale on a graduate into which they fall, or else, 
 as Nicolai finally developed the method, they drop upon 
 the receiving arm of a Marey tambour and are re- 
 corded upon a revolving drum. 
 
 Along with the study of the diff^erences in the se- 
 cretory reflexes to various edible and non-edible sub- 
 stances the discovery was made that any phenomenon 
 of the external world which is capable of impinging 
 upon the organism through any one of the sense or- 
 gans may become the excitant of the secretory re- 
 flexes ordinarily functioning in response to nutritive 
 substances only. When the secretion is poured out by 
 the glands as the result of the presentation of food 
 the reflex is said to be a natural or unconditioned one. 
 When, however, it functions in reaction to auditory 
 stimulation by an arbitrary sound, or in response to 
 a mechanical stimulation of the skin or to the presenta- 
 
64 CHILD BEHAVIOR 
 
 tion of a colored light or to any other stimulus not 
 usually accompanying the feeding, then the reflex is 
 said to be "artificial" or "conditioned." The stimulus 
 which is the excitant of this conditioned reflex is called 
 the "conditioned" stimulus. 
 
 The conditioned reflex is established as follows: At 
 the same time that the dog (which is the animal that 
 has been generally used in the Pavlov laboratory) is 
 given a piece of meat or other food that stimulates the 
 activity of the reflex, the stimulus which has been 
 picked to become the associated excitant of the reflex is 
 also presented. This simultaneous presentation of the 
 conditioned stimulus and the natural stimulus (i e., the 
 food) is repeated a number of times until at last the as- 
 sociation has been so well established that the artificial, 
 conditioned or unnatural stimulus, as it is variously 
 called, will, when presented alone, excite the secretion. 
 
 These conditioned reflexes have several pecularities 
 which have been verified by repeated experimentations. 
 1. They are unstable or inconstant. 2. They become 
 ineff^ective upon repetition, inversely according to the 
 time interval between the successive excitations of the 
 reflex by use of the conditioned stimulus. 3. Oblitera- 
 tion of one reflex does not aff^ect the functioning of oth- 
 ers. 4. Spontaneous reappearance takes place only 
 after one, two or more hours. 5. A conditioned reflex 
 may be redeveloped by renewed association with the 
 unconditioned reflex with which it was first associated. 
 
 The work of Pavlov himself seems to be purely physi- 
 ological and medical in its interests. True, he speaks 
 of, and experiments upon, the "psychic excitation" of 
 the digestive secretions, but these so-called "psychic ex- 
 citations" are merely all those stimuli which work oth- 
 erwise than by direct temperature, chemical and me- 
 
BEHAVIORISM AND CHILD PSYCHOLOGY 65 
 
 chanical excitations by the food entering the buccal 
 cavity. The conclusion of his speech presented in the 
 Huxley lectures on recent advances in science and their 
 bearing on medicine and surgery shows this clearly. 
 There he says, "The investigation of the conditioned 
 reflex is of very great importance for the physiology 
 of the higher parts of the central nervous system. 
 Hitherto this department of physiology has throughout 
 most of its extent availed itself of ideas not its own, 
 ideas borrowed from psychology, but now there is a 
 possibility of its being liberated from such evil influ- 
 ences. The conditioned reflexes lead us to the consid- 
 eration of the position of animals in nature; this is a 
 subject of immense extent and one that must be treated 
 objectively" (128, p. 618). He ends with the predic- 
 tion that these facts will throw light upon the "highest 
 and most complicated portion of the animal mechan- 
 ism" (128, p. 619). 
 
 This method has been very widely used on dogs but as 
 its application involves the formation of a fistula for 
 the study of almost any of the secretions it was thought 
 to be inapplicable in the study of human beings. Modi- 
 fications of method have arisen which are more promis- 
 ing. Kalischer (88, 89) trained dogs to eat when he 
 presented certain tones, and to refrain from eating 
 when all others were presented simply by associating 
 the feeding with one tone only and found the dogs 
 made no attempt to get the food he held in his hand un- 
 less the correct tone had been sounded. Similar meth- 
 ods might be used with young children. 
 
 To Bechterew (10) we owe, however, a more radical 
 and valuable modification. The work of Pavlov though 
 fundamental for the development of the theory of men- 
 tal activity as reflex in its nature is too narrow in its 
 
66 CHILD BEHAVIOR 
 
 application to function as the basis of all psychology. 
 Bechterew approaches the same subject from the psy- 
 chological rather than the physiological viewpoint and 
 hence applies his experimental data in that field. While 
 Pavlov's work centers about the secretory reflexes, 
 Bechterew studies the motor reflex. One method of 
 studying it is as follows. The reflex movement of the 
 withdrawal of the foot from metal electrodes through 
 electrical stimulation is accompanied by the presenta- 
 tion of some other stimulus such as the flash of an 
 electric light bulb, the ringing of a bell or the appear- 
 ance of a colored form before the subject. After a cer- 
 tain number of trials the presentation of the arbitrarily 
 chosen stimulus without the accompaniment of electri- 
 cal stimulation will suflice to cause the raising of the 
 foot. Voluntary movements are also used under various 
 controlled conditions. 
 
 To Bechterew all activity is reflex activity or re- 
 sponse to stimuli external to the organ or group of mus- 
 cles reacting. He writes that he has observed in detail 
 the development of reflexes in his five children through- 
 out their earliest childhood but he gives us no state- 
 ment of results other than a general theorizing regard- 
 ing movements and language development as condi- 
 tioned reflexes. 
 
 In this country Watson (185) has attempted an ap- 
 plication of this method to human beings using Bech- 
 terew's method of electrical shock but substituting in 
 his later work the movement of the fingers for foot 
 and toe movements. The study is interesting to us be- 
 cause of its use upon one child, an eight-year-old boy. 
 The experiment is reported as follows : "Whether the 
 method can be used widely with children has not been 
 determined. In the course of twenty minutes we ob- 
 
BEHAVIORISM AND CHILD PSYCHOLOGY 67 
 
 tained the reflex several times upon an eight-year-old 
 boy. When first punished he cried and showed some 
 reluctancy towards having the experiment continue. 
 One of the experimenters then sat in the room with him, 
 and, under promise of a moving picture show after the 
 experiment, the series was completed with smiling forti- 
 tude" (p. 102). 
 
 This simple report of what happened shows very 
 significantly that the punishment method is apt to put 
 the child into an unfavorable frame of mind and re- 
 sults obtained upon him will consequently not be com- 
 parable with those obtained from adults who under- 
 stand the aim of scientific experiments. With younger 
 children it is also highly improbable that the promise of 
 some reward would carry them through the necessary 
 number of trials and the mothers themselves would 
 probablj' object. 
 
 One point is exemplified that can not be too em- 
 phatically stressed, no matter what method of study- 
 ing the child is used. That is the need of getting en 
 rapport with the child, of understanding him and know- 
 ing what will appeal to him and keep him interested in 
 the experiment. The adult can be verbally directed 
 towards the task that is set him in the experiment and 
 by his acceptance of the direction is attitudinized to- 
 wards the work expected of him and the value of the 
 results for science will be sufficient as a goal idea. But 
 the child wants immediate reward and also does not 
 want to devote any of his time to things that are not 
 innately attractive. He must be ruled by interest, not 
 by forced attention. 
 
 Watson points out the application of this method 
 in the study of sense perception, acuity and discrimina- 
 tion in all senses, memory and the so-called association 
 
68 CHILD BEHAVIOR 
 
 reaction work, also in determining sensory integrity in 
 those who for some reason or other do not speak. 
 
 The application to the study of learning cannot come 
 by this method unless it is modified. He gives five ex- 
 periences with the shock and the other stimulus work- 
 ing together, then tries the conditioning stimulus alone. 
 If it does not cause the reflex to function, he gives five 
 more simultaneous stimulations before he tries it again. 
 By this method he knows only that the conditioned re- 
 flex has established itself somewhere in the series of five, 
 while a trial of the functioning ability after each pun- 
 ishment stimulus would give the exact point of develop- 
 ment. 
 
 Another line of investigation using the Pavlov 
 method of secretions was begun by Bickel and Bogen. 
 Bickel had the opportunity to observe a 23-year-old 
 girl with a fistula of the esophagus and stomach and 
 found that, just as in the Pavlov dogs, "The different 
 stimuli, which touch the taste or smell organ, suffice 
 to cause a secretion or increase a secretion already in 
 flow" (12, p, 591). He did not, it seems, attempt 
 any serious experiments in an effort to develop condi- 
 tioned reflexes. 
 
 Bogen (17) was familiar with some of the earlier 
 reports of Bickel and consequently when a similar case 
 presented itself in the Children's Clinic at the Univers-^ 
 ity of Heidelberg he studied it not only for the reflex: 
 secretion to natural stimuli but for the artificial or con- 
 ditioned reflexes. 
 
 The case was a boy three and a half years old who* 
 had drunk some lye and gradually developed complete 
 stegnosis of the esophagus so that finally a stomach 
 fistula was made and used for feeding while curative 
 measures were attempted. The experiments were car- 
 
BEHAVIORISM AND CHILD PSYCHOLOGY 60 
 
 ried out while the child was in the hospital. 
 
 The child was laid on his stomach on two out- 
 stretched towels which did not meet but allowed the 
 canula to pass between. The child could not see what 
 was going on in the room. Then he was fed milk or 
 meat and the gastric justice would begin flowing al- 
 though the food was regurgitated as it could not reach 
 the stomach. "After about 6 such experiments had 
 been made it also happened that the sight of the meat 
 as well as of the milk called forth a psychic secretion of 
 gastric juice" (p. 736). Then the associative experi- 
 ment was used. "The child was fed a long time — in all 
 over 40 times — with meat, while simultaneously a cer- 
 tain tone was blown upon a small trumpet" . . . 
 Other combinations were also used, the showing of food 
 and blowing the trumpet, etc. and "all these experiments 
 gave positive results" (p. 73T). Finally in ten trials 
 of the blowing of the trumpet seven were followed by 
 secretion and only three were negative. Anger and 
 pain delayed the secretion, the period of latency for 
 meat was four and three-quarters minutes, for milk, 
 nine minutes, and the secretion decreased as the in- 
 tensity of stimuli decreased. 
 
 So far we see little indication of a method which can 
 be easily applied to the normal child of any age inde- 
 pendent of his ability to speak or understand the spok- 
 en word, or readily adapted for the study of many 
 processes, one that does not force the child into an un- 
 pleasant situation but that invites his cooperation 
 through arousing his interest and which nevertheless 
 is thoroughly in accord with scientific theories and is 
 able to evoke through its use data scientifically valu- 
 able. 
 
 From the work of Pavlov, Bechterew, and Kostyleff 
 
70 CHILD BEHAVIOR 
 
 (97) who has given the theoretical application of the 
 idea of the conditioned reflex its highest development; 
 from the work of Verworn (179), Sherrington (155) 
 and Loeb (105), and from the work of the behavior 
 psychologists already mentioned we have, however, 
 evolved a theory of the child which we can use to de- 
 velop the working rules for the scientific study of him. 
 
 The child, becoming at birth independent in his ex- 
 istence, is an irritable organism with a potentiality for 
 many diverse forms of activity. This irritability is at 
 first not highly specific but practically any stimulus 
 calls forth a diffuse reaction. Within the organism, 
 however, certain reactions have already been deter- 
 mined in a very specific manner by the completed de- 
 velopment of the neural paths subserving those reac- 
 tions. These are the first instincts. Gradually spe- 
 cific neural paths or neural habits of reaction develop 
 for many more and far more varied stimuli. These re- 
 actions are instinctive if they are independent of the ex- 
 perience of the individual previous to their functioning, 
 habits if they are dependent upon his earlier experience. 
 
 Any stimulus in the environment of the individual 
 may become the excitant of a reaction which may be- 
 come habitual. The type of reaction which any one 
 stimulus may excite is not specific but is of an excess- 
 ively varied potentiality. Any reaction of the child at 
 any time is dependent not only upon his environment at 
 that time but also upon the sum total of his earlier ex- 
 periences and likewise not independent of his eff^ectively 
 inherited predispositions, that is the specific tendencies 
 or incapacities of his organism. 
 
 The complexity of the conditions is increased by the 
 fact that the child is a growing organism. Habits are 
 formed, specific reactions developed, not only because 
 
BEHAVIORISM AND CHILD PSYCHOLOGY 71 
 
 of the plastic receptivity of his organism but all activ- 
 ity and functioning is favored by the very nature of 
 the child himself. His fundamental necessity is growth. 
 The great strides which the most casual observer notes 
 in the young child are the result of simultaneity of 
 growth in structure and growth in function which we 
 call adaptation or learning. 
 
 From this we may formulate the theorems basal for a 
 scientific method of studying child behavior. 
 
 1. The child is a responsive organism. 
 
 2. Response may be structural and so involves 
 growth. 
 
 3. The study of structural responses, as a type of 
 adaptation and learning, is the necessary concomitant 
 of the study of neural response. The two are not an- 
 tagonistic. The presence of one does not, as has often 
 been claimed, impede the study of the other. They are 
 necessary correlates and their correlated presence dis- ' 
 tinguishes the study of the child from the study of the 
 adult which is largely one of interest in function. 
 
 4. All neural response is of the reflex type, that is, 
 direct response to a stimulus or group of stimuli. 
 
 5. The neural response is never arbitrary but al- 
 ways motivated by a definite stimulus although for any 
 one stimulus the response may vary greatly, and, vice 
 versa, any one response may at different times be 
 caused by widely diff^erent stimuli. 
 
 6. The child responds to all in his environment for 
 which sense specificity has developed but primarily to 
 the most effectively sensed stimuli. 
 
 7. Any stimulus quality in the external world may 
 be brought into causal or inhibitory relation with any 
 reaction or group of reactions of the functioning or- 
 ganism and probably none is without structural effect. 
 
72 CHILD BEHAVIOR 
 
 The next question is as to the methods by which 
 this theory may be applied to the study of the young 
 child. Baldwin in his dynamogenic method comes very 
 near giving one solution, while Warner's work on hand 
 movements approaches a similar and more exact solu- 
 tion of the same thing. But neither of these men had 
 the apperceptive background of method and knowledge 
 of the conditioned reflex which in Krasnogorski led in- 
 evitably to its application to the study of children. His 
 work far exceeds in suggestiveness anything preceding 
 it, although it should be mentioned that the work of 
 Bickel and Bogen seems to have been an incentive to 
 him. His method and its application are, however, his 
 own. 
 
CHAPTER IV 
 THE EXPERIMENTS OF KRASNOGORSKI 
 
 THE first definite application of the Pavlov method 
 to normal children was made by Krasnogorski. 
 In 1907, in the Russki Wratsch (98), he presented 
 the results of a study of conditioned reflexes as devel- 
 oped in sucklings. Using one fourteen-month-old baby, 
 he studied the cortical activity as indicated by salivary 
 secretion. He had the child in a room by itself, lying 
 on a table, no noise or other changing factor being al- 
 lowed to disturb the conditions, and even the movements 
 of the experimenter being kept as constant as possible. 
 After a few trials in which the child was excited by 
 the sight of food (milk in a glass) held at a distance 
 there was an increasing frequency of swallowing move- 
 ments and also a motor reaction of mouthing and suck- 
 ing. Krasnogorski felt that this presented such a spe- 
 cific picture that it might well be used to study the con- 
 ditioned reflexes in normal cases where there was no 
 salivary fistula by means of which the salivary secretion 
 could be studied. 
 
 In children even the most unimportant salivary se- 
 cretion, of even 0.5 of a square centimeter, induces the 
 act of swallowing and by the number of swallowings in 
 a given time one can judge the force of secretion. In 
 this instance the child studied had been fed and had 
 then enjoyed a short rest before being brought under 
 the experimental conditions. 
 
 73 
 
74 CHILD BEHAVIOR 
 
 A glass with milk in it was shown with the following 
 results : 
 
 Record of Number of Swallows in Three Minutes 
 
 First Second Third 
 
 Observation Observation Observation 
 
 Before 13 3 
 
 stimu- 3 3 2 
 
 lation 2 3 
 
 2 13 
 
 Excited by food 9 16 10 
 
 When the auditory stimulus of a ringing bell was 
 used the following results were obtained in a 3- to 5- 
 minute interval after the ringing of the bell, "after a 
 certain number of trials" (he does not state the num- 
 ber). 
 
 Record of Number of Swallows in Three 
 
 TO Five 
 
 Minutes 
 
 
 
 
 First 
 
 
 Second 
 
 
 Third 
 
 Observation 
 
 Observation 
 
 Observation 
 
 3 
 
 
 3 
 
 
 5 
 
 Before 4 
 
 
 
 
 
 excita- 2 
 
 
 3 
 
 
 4 
 
 tion 2 
 
 
 
 
 
 
 
 
 2 
 
 
 4 
 
 During 
 
 
 
 
 
 stimulation 6 
 
 
 8 
 
 
 8 
 
 From these observations Krasnogorski concludes: 
 The amount of secretion in response to the auditory 
 
 stimulation is in quantitative relation to the amount 
 
 secreted during the foreperiod. 
 
EXPERIMENTS OF KRASNOGORSKI 75 
 
 If the unconditioned stimulus used is one producing 
 a relatively great amount of saliva then the amount ob- 
 tained from excitation by a conditioned stimulus built 
 up upon this basis is correspondingly great as meas- 
 ured by the increasing frequency of swallowing. 
 
 If the child cries when he sees food and does not get 
 it this interferes with the conditioned reflex, having an 
 unfavorable influence upon it, and the experiment can 
 be resumed with favorable results, only when the child 
 again becomes quiet. 
 
 Later Krasnogorski modified and perfected his pro- 
 cedure considerably. A first full report of the find- 
 ings with these improved methods was made by him in 
 1908 at the meeting of the Society of Children's Physi- 
 cians in Petrograd. 
 
 He had been studying the secretion of saliva by 
 counting the number of swallowing movements which, 
 being dependent upon the secretion itself, might natur- 
 ally be expected to vary with it in intensity and dura- 
 tion. But there intervened a period between the first 
 stimulation by a food quality and this movement, a 
 period in which saliva was being secreted but had not 
 yet accumulated in sufficient quantity to stimulate the 
 swallowing reflexes. Other movements were present and 
 noticeable, however. 
 
 These were movements of mouth opening as prepara- 
 tion for food reception. Accordingly he changed his 
 observation to a record of the combined movements of 
 mouth opening and swallowing. These were recorded 
 by the simple arrangement of the receptive plate of a 
 Marey tambour placed over the thyroid cartilage or the 
 hyoid bone, connected by a rubber tubing with a re- 
 cording arm which traced each movement upon a ky- 
 mograph. 
 
76 CHILD BEHAVIOR 
 
 The child, with recorder in position, was "placed in 
 absolute quietness upon a table in an isolated room. 
 The eyes of the child were bandaged to avoid visual 
 stimuli, if the conditioned reflexes were developed from 
 various other receptive sensory surfaces" (99, p. 10). 
 Taking first a control record of a quiescent state he 
 next stimulated the child by feeding chocolate or honey. 
 In the curves recording this feeding the initial devia- 
 tion marking mouth opening may be easily diflPerenti- 
 ated from the swallowing records following. Such a 
 "natural" or unconditioned reflex is too complex to al- 
 low of satisfactory analysis, consequently the effort 
 was made to establish "conditioned" or "artificially de- 
 veloped" reflexes. 
 
 Three children were used, one three years old and 
 two six years old. First the conditioned reflex was es- 
 tablished in the 3-year-old by the ringing of an electric 
 bell for one minute, every third minute with the ac- 
 companying feeding of one-half teaspoonful of honey 
 fifteen seconds after the ringing started. This was re- 
 peated until the ringing of the bell was sufficient to 
 cause the feeding movements. The association lasted 
 and functioned two weeks after its last developmental 
 functioning. The same conditioned reflex was devel- 
 oped in one 6-year-old and the "reaction after 24 hours 
 was weaker than a second reaction 25 minutes later" 
 (99, p. 13). 
 
 In both 6-year-olds the reflex was developed to the 
 sounding of a tone on the reed pipe. Chocolate was 
 given 10 minutes after the beginning of the sound. Al- 
 though the note gave the reflex action yet similar re- 
 action occurred to other tones. Seemingly, tonal dis- 
 crimination is not as well developed in the child at 
 six as Seleni and others find it to be in the dog. Nor 
 
EXPERIMENTS OF KRASNOGORSKI 77 
 
 did re-enforcement of only the response to the correct 
 tone by chocolate feeding seem propaedeutic of in- 
 creased tonal discrimination. 
 
 Krasnogorski also used cutaneous stimulation, 
 scratching a place on the skin lightly with a camel's 
 hair brush for one minute and, after 15 seconds of the 
 mechanical irritation, associatively feeding chocolate. 
 This stimulus soon became an adequate excitant of the 
 feeding reflexes. But in the 6-year-olds the stimulus 
 was not spatially specific, the same response in the re- 
 flex followed scratching upon the foot as had been de- 
 veloped to scratching of the arm above the elbow. 
 Spatial specificity of excitation of reflex was secured in 
 the 6-year-olds, however, by alternating stimulation of 
 the particular spot first used and feeding, with stimula- 
 tion of other portions of the body without feeding. In 
 the 3-year-old child the stimulation had a specific and 
 local value from the first. 
 
 The question of the decadence or unlearning of the 
 conditioned reflex next occupied Krasnogorski's at- 
 tention. A 6-year-old was put in a quiet position and 
 the child stimulated by sight of food held before him 
 without his being fed. This was continued 30 seconds. 
 After 5 minutes a second stimulation was similarly con- 
 ducted, a third, and then on the fourth no reaction 
 occurred. Then the child was given some honey and the 
 reaction immediately reappeared. 
 
 With the other 6-year-old, where a conditioned reflex 
 had been developed to the ringing of an electric bell 
 every 10 minutes for 30 seconds, the disappearance 
 took place gradually being completed in five trials. 
 When the pauses between stimulations in this same child 
 were only 5 minutes the inhibition occurred after three 
 trials. The reflex was renewed by one associative func- 
 
78 CHILD BEHAVIOR 
 
 tioning of conditioned stimulus and feeding. 
 
 The breaking down of the reflex as conditioned by 
 mechanical stimulation occurs with a 6-year-old child 
 after 3 trials, being absent on the fourth and fifth 
 trials. 
 
 A second series of experiments was carried out in 
 which the working of the feeding, or natural stimulus, 
 and the artificial stimulus instead of being simultaneous 
 were successive. Mechanical stimulation was used, for 
 example, and after its application for 30 seconds there 
 was a pause of 10 seconds and then the child was fed 
 in the 11th second. After 16 such associated func- 
 tionings the scratchings acted as a conditioning factor 
 in the 17th trial. This reaction occurred during the 
 early part of the scratching period, but during sub- 
 sequent repetitions it appeared more and more slowly 
 until it was present only after the cessation of the 
 scratching. The child was lively and very exceptional 
 in endowment and attempts to break down the condi- 
 tioned reflex were very slow in taking eff*ect. It took 
 eleven functionings without feeding before, on the 
 twelfth stimulation, we find a complete dissolution of the 
 reaction. In disappearing the reflex maintained the 
 temporal position developed earlier of functioning after 
 the period of stimulation. 
 
 Krasnogorski did not in this study ascertain the 
 value of reflexes during sleep or relative values at dif- 
 ferent ages although he states that in decadence the re- 
 flexes are "diff^erent in diff^erent children" (99, p. 24). 
 
 In 1913 Krasnogorski presented a second report of 
 his work at the International Medical Congress held in 
 London. Evidently, in spite of the brevity of his re- 
 port, the results he has achieved are conclusive to him 
 for he says, "Each phenomenon of the external world, 
 
EXPERIMENTS OF KRASNOGORSKI 79 
 
 which is received by the peripheral systems of the child, 
 can be brought into a temporary association with a 
 motor, that is a secretory, act. All possible stimuli of 
 sight, hearing and skin can be metamorphosed into spe- 
 cific excitants and call forth a definite motor act if their 
 effect as stimuli is temporally associated with the motor 
 act several times" (100, p. 376). 
 
 Without giving detailed results (or in fact any spe- 
 cific data) he states that in normal children S-10 trials 
 is sufficient to establish an associative functioning ; that 
 the conditioned reflexes so established are of "high 
 stability" and "easy inhibition," but that there is a wide 
 range of innate individual variation and he also inti- 
 mates, but does not actually state, a diff*erence due to 
 chronological age, for he writes : "In normal infants the 
 cortical innervations are so little developed in the first 
 two or three months of life that the conditioned asso- 
 ciations usually can not be developed. But as early as 
 the second half of the first year of life the development 
 of temporary associations from all receptive surfaces 
 (eyes, ears, nose, skin) is indeed possible, but occurs 
 more slowly than is the case in later life. Only in the 
 course of the second year of life does the mechanism of 
 the conditioned reflexes reach its full development and 
 functional perfection" (100, p. 376-377). 
 
 Moreover Krasnogorski asserts that all sorts of 
 pathological states cause changes in the activity of the 
 conditioned reflexes ; fever periods reduce activity, while 
 "In many cases of idiocy, in neuro-psychopathic chil- 
 dren, in cases of organic lesions of the cortex the de- 
 velopment of the temporary association is either entire- 
 ly impossible or else very much more difficult" (100, 
 p. 377). 
 
 The dissolution of these conditioned reflexes is also 
 
80 CHILD BEHAVIOR 
 
 very interesting and exceedingly valuable Krasnogorski 
 believes. In neuropathic children this process is un- 
 usually difficult. He gives as an example the case of 
 a five-year-old boy where the conditioned reflex in re- 
 sponse to cutaneous stimulation developed "propor- 
 tionately easily" and where thirty-one repetitions of 
 the conditioning stimulus without accompanying feed- 
 ing were necessary before the dissociation was effected. 
 
 The memory-conditioned reflexes are also more fully 
 treated in this report. Unlike the memory conditioned 
 reflex of the dog which lacks specificity and disappears 
 easily "high specificity and extraordinary precision 
 are usual characteristics of this group of the reflexes 
 in human beings . . . the memory reflex is formed 
 just as easily as the usual contemporary associations. 
 It is sufficient to cause the memorial eff'ect of some sort 
 of a stimulus to occur together with the opening of the 
 mouth only 20-30 times in order for these memory 
 traces to become adequate excitants" (100, p. 379). 
 As this memory reflex develops at a later age, shows 
 lessened specificity in many neuropathic children, and 
 is more difficult to develop in imbeciles and morons its 
 clinical significance is great. 
 
 The next mechanism w^hich Krasnogorski has investi- 
 gated is that of the analysers. Analysers, according to 
 the Pavlov and Krasnogorski terminology are "those 
 neural apparatus which analyze and resolve the stimuli 
 of the external world into the minutest parts in order 
 to build up from these fractional bits new combina- 
 tions which represent the regular projection of these or 
 those external phenomena" (100, p. 380). Dogs have 
 the auditory analyser perfected to the discrimination 
 of differences of an eighth of a tone while with children 
 it is very poorly developed, but with them the visual an- 
 
EXPERIMENTS OF KRASNOGORSKI 81 
 
 alyser is much more highly developed than with the dog. 
 Red and white lights are discriminated by 5- to 6- 
 months-old normal infants, odors are differentiated 
 without great difficulty at the age of 7 to 8 months 
 while the skin analyser is well developed towards the 
 end of the first year. The movement analyser or motor 
 zone is very poorly developed during the first year, 
 but reaches its full development in the course of the 
 second year of life. 
 
 Analysing ability is greatly decreased in idiot and 
 imbecile children, may be disturbed temporarily or per- 
 manently in neuropathic conditions, appearing less 
 readily and fluctuating more easily. A most marked 
 example of disturbance of the motor analyser is to be 
 found in the hysterical paralyses. 
 
 "The clinical investigation of the ability of the an- 
 alysers to differentiate as made by means of the condi- 
 tioned motor reflexes appears to be the sole objective 
 clinical method which permits the determination of the 
 analyser activity of a definite portion of the cortex 
 as well as the discrimination of pathological processes. 
 
 Each neural process consists, as is known, of the 
 phenomena of stimulation and of innervation — they 
 are in a manner two halves of one and the same activity 
 of the nervous system. The normal course of these 
 nerve processes depends upon the balancing, upon the 
 equal force, of these two forms of energy. Consequently 
 it is comprehensible what unusual significance apper- 
 tains to the mechanism which lies at the bottom of cor- 
 tical innervations" (100, p. 384-385). 
 
 The method of conditioned reflexes, because of the 
 delicate fluctuations in the reflex due to changes in the 
 organism gives us an excellent measure of the interplay 
 of reactions, of inhibition, and discharge in any one cor- 
 
82 CHILD BEHAVIOR 
 
 tical center. At first the stimulus of any one sense ex- 
 cites the whole cortical area of that sense and all such 
 stimulation is followed by the associated reflexes of 
 feeding. But as only one part of that sense organ is 
 stimulated in association with the natural conditioning 
 of feeding gradually the rest of that group of cortical 
 analysers develops an inhibitory condition and only 
 the selected and specific stimulation arouses the reflex. 
 This specificity of reaction is rapidly lost and is very 
 unstable. "One must assume," writes Krasnogorski, 
 "that the whole cortege is filled with such conditioned 
 centers, which quicMy arise, quickly disappear, quickly 
 develop in size, soon grow smaller and are always hound 
 up with this or that system^ of the cortex according to 
 the conditions of their arousal'^ (100, p. 388). 
 
 The formation of this specific conditioned reflex in 
 animals passes through three stages. First the at- 
 tempted inhibition brings accompanying inhibition of 
 the desired reaction also, then "stimulation of the inac- 
 tive part induces a reflex but its disappearance is not 
 followed by the disappearance of the reflex from the ac- 
 tive part; in the third phase . . . the phase of 
 absolute differentiation, the inactive stimulation excites 
 neither secretory nor motor reaction any longer, al- 
 though the stimulation of the active part shows its max- 
 imum result" (100, p. 388). In children, however, 
 Krasnogorski finds the first two phases little differenti- 
 ated and absolute differentiation rapidly develops ex- 
 cept in very young infants and in neuropaths where the 
 second phase is almost always clearly lengthened. In 
 idiocy, imbecility and myxoedema "the formation of 
 conditioned centers takes place with unusual difficulty" 
 (100, p. 388) while in excitable neuropathy "the stabil- 
 ity of the conditioned centers appears greatly reduced" 
 
EXPERIMENTS OF KRASNOGORSKI 83 
 
 (100, p. 388). The "inner inhibition" is more inert 
 in young children and only reaches its functional ma- 
 turity in children between three and four years of 
 
 Another mechanism discovered by Pavlov's labora- 
 tory and used by Krasnogorski is that designated as a 
 "conditioned inhibition." By associating any stimulus 
 with the working of a previously established conditioned 
 reflex, without accompanying feeding, the new stimulus 
 becomes in a short time the adequate stimulus for inhi- 
 bition of the action of the conditioned reflex which it 
 accompanied but this conditioned reflex functions as 
 usual when the inhibiting stimulus is not applied. 
 
 This inhibition Krasnogorski finds develops in nor- 
 mal children in from five to ten trials. It then has a 
 strong inhibitory eff*ect, breaks down easily and disap- 
 pears slowly if left to time. In gross pathological 
 cases, however, the inhibition develops more slowly, is 
 less eff*ective and disappears very quickly. In neuro- 
 pathic children the inhibition behaves difl'erently ac- 
 cording to the type. The excitable neuropath develops 
 the inhibition easily, but it breaks down easily and dis- 
 appears rapidly under lapse of time. In the phlegmatic 
 child it develops slowly and only in response to rela- 
 tively strong stimuli and it may, although not always, 
 last a considerable period. 
 
 The most complex mechanism evolved by Krasno- 
 gorski is that of "loading and discharge." A condi- 
 tioned reflex is developed in response to a stimulus 
 through any sense organ and any chance development 
 of a conditioned reflex in response to stimulation of 
 some other sense is broken down by the repetition of the 
 stimulation without feeding. Then the conditioning 
 stimulus is given and no feeding but a presentation of 
 
84 CHILD BEHAVIOR 
 
 the non-conditioning stimulus follows and the feeding 
 follows it. Then the non-conditioning stimulus is given 
 again without accompanying feeding. Thus the reflex 
 develops in sequential order as response to the first 
 stimulus, formerly indiff^erent, after the conditioning 
 stimulus. Krasnogorski used ringing a bell one-half 
 minute, then 3 minutes later stimulating the skin. "In 
 this case," he writes, "the skin stimulation appears, so 
 to speak, as the trigger of the charge weapon. We 
 load the neural mechanism with the stimulation by the 
 ringing of the bell, this lading remains in the cortex and 
 can be discharged at a favorable moment, if we set in 
 motion our depressing mechanism — the skin stimula- 
 tion" (100, p. 391-392). 
 
 In view of the clinical significance which Krasnogor- 
 ski claims for this mechanism it is worth while to give 
 here his physiological explanation of it. "The ele- 
 ments of the hearing analyser were brought into a co- 
 temporal association with the motor cells. Then we 
 changed the conditions of our experiments in that we 
 did not let the unconditioned stimulus (the giving of 
 chocolate) occur together with the ringing of the bell, 
 but with a stimulation of the skin following a little 
 afterwards. Consequently an inner inhibition was de- 
 veloped in the hearing analyser which restrained the 
 energy of the bell stimulation in a latent condition, did 
 not permit it to pass over into the motor elements. In 
 contrast the cortical elements of the skin analyser are 
 in no co-temporal association with the motor elements 
 — as we have seen, the skin stimulation as such arouses 
 no motor act. The skin analyser is exclusively in a co- 
 temporal contact with the inhibiting mechanism of the 
 hearing analyser. Therefore it is clear that as soon as 
 the skin stimulation is received and the elements of the 
 
EXPERIMENTS OF KRASNOGORSKI 85 
 
 skin analyser are set in motion, the wave of the stimu- 
 lation (the positive energy) must tend over the paths 
 developed towards the inhibiting mechanism of the hear- 
 ing analyser. The inhibiting energy (negative energy) 
 which is concentrated in the hearing analyser is thereby 
 neutralized and consequently the inhibiting mechanism 
 is weakened and the charge of positive energy of the 
 hearing analyser is freed from the inhibition. This 
 energy of the hearing analyser will be conducted, by 
 the temporary associations by which the hearing analy- 
 ser is connected with the motor element, to the latter 
 and will call forth, as we have seen, a motor reaction" 
 (100, p. 392). 
 
 This mechanism was developed in a five-year-old child. 
 A cutaneous conditional reflex was developed and then 
 a ringing of a bell introduced with skin stimulation 2 
 minutes later. No reaction appears but to the next 
 skin stimulation ten minutes later a reaction is evi- 
 dent. 
 
 This mechanism does not function before the end 
 of the second year of life and only reaches its full 
 development in the third year. In excitable neuropaths 
 this mechanism develops rapidly but also disappears 
 easily. These are the children who learn rapidly and 
 forget just as readily. In the phlegmatic neuropath 
 the mechanism forms slowly and then in some imbeciles 
 is very unstable while in others it is persistent. Some 
 children who learn very readily also keep the acquired 
 reaction very persistently. 
 
 These six mechanisms, co-temporally conditioned re- 
 flexes, their inhibition, memorially-conditioned reflexes, 
 specific memory reflexes, ability of analysers, lading 
 and discharge, give us an objective measurement of the 
 child's neural assets which must replace the so-caUed 
 
86 CHILD BEHAVIOR 
 
 intelligence testing. They will also give us a definite 
 means of clinically separating the pathological cases 
 in early childhood. 
 
 Krasnogorski asserts also that (in epileptics) their 
 functioning will indicate the onset of a convulsion and 
 pass through four stages of re-development of their 
 power of functioning after a convulsion. In myxce- 
 dema the reflexes develop slowly and disappear rapidly. 
 Thyroid treatment does not change the manner of func- 
 tioning of these reflexes. 
 
 There is a diminution of activity of these mechanisms 
 in the beginning of tubercular meningitis and this de- 
 crease is constant and progressive. 
 
 By means of the study possible at an early age by 
 use of these mechanisms defects discovered may be cor- 
 rectively and educationally dealt with long before they 
 are usually noticed and the possible value and signifi- 
 cance of this training may be enormous. 
 
 CRITICISM OF KRASNOGORSKl's STUDIES 
 
 Promising and valuable as Krasnogorski's work may 
 appear to even the casual reader, no one would deny 
 that it is suggestive rather than decisive, initial rather 
 than final and inspirational rather than scientific so far 
 as the data published are concerned and there are sev- 
 eral points open to criticism. 
 
 In his statement regarding technique Krasnogorski 
 shows he has eliminated all disturbing stimuli from the 
 external world by ensuring a quiet room and a quiet 
 subject in a position of relaxation. One important 
 factor he has entirely neglected despite these precau- 
 tions. That is the child himself. No mention is made 
 as to how he was induced to assume the position, as to 
 
EXPERIMENTS OF KRASNOGORSKI 87 
 
 whether he was familiar with the experimenter, what his 
 emotional reaction to the situation was, what his atti- 
 tude mentally was, that is, was he bribed or threatened 
 or coaxed. In fact that whole externally-undetectable 
 group of factors is not even hinted at although more 
 detailed statements as to how the child was handled 
 might throw some light upon the results obtained. 
 
 No mention is made by Krasnogorski of the criteria 
 used to determine the mental development of his sub- 
 jects. Idiots, imbeciles, cretins, hysteria cases, neuro- 
 psychopaths, epileptics, have all evidently been studied 
 as well as normal children, but of how many and of 
 what ages, degree of pathological characterization, and 
 hereditary predisposition we can unfortunately find no 
 statement. 
 
 In his work to determine pitch discrimination Kras- 
 nogorski used a reflex developed upon a feeding delayed 
 ten minutes after the "beginning of the sound." How 
 long the sound was kept up we do not know, but the 
 conditions seem rather unfair either way. If the sound 
 were continued half the time subjective changes such as 
 those due to fatigue, anticipation and fluctuation of at- 
 tention would make final discrimination of the sound 
 difficult when compared with another at least five or 
 ten minutes later. If the bell rang or tone sounded 
 only a few seconds the difficulty would be to tell to what 
 extent the child remembered and how far he forgot the 
 stimulus in the eight- or nine-minute interval. Prob- 
 lems on tonal discrimination undertaken with adults re- 
 port great difficulty in discrimination when tones are 
 immediately successive. 
 
 Although he states that the conditioned reflex is very 
 difficult to develop in children under one year of age, yet 
 Krasnogorski has used it to determine color discrimina- 
 
88 CHILD BEHAVIOR 
 
 tion at the age of six or seven months, showing that that 
 mechanism can be developed at such an age. 
 
 The time intervals in the various experiments differ 
 without any seeming rationality. In one series the stim- 
 ulation was of one minute's duration and with two min- 
 utes between successive stimulations, and feeding was 
 fifteen seconds after initiation of the stimulation. In 
 testing dissolution of the reflex thirty seconds of stimu- 
 lation at five minute intervals was used. In another 
 case the reflex was developed by thirty seconds of stim- 
 ulation applied every ten minutes, while dissolution was 
 attempted with both five- and ten-minute periods. 
 
 Since in this latter case the results obtained on the 
 same child varied with the time interval we must con- 
 sider this interval an Important factor. In order that 
 results may be at all valuable for comparison it must 
 be kept as nearly constant as possible. If one develops 
 a conditioned reflex with a minute's stimulation once 
 every three minutes and breaks It down with thirty sec- 
 onds of stimulation every five minutes there are two 
 variables in the time factor alone and the value of the 
 variation between development and dissolution cannot 
 be calculated except through results obtained by numer- 
 ous series of experiments. Undoubtedly a minute's 
 stimulation is dlff^erent from a half minute's application 
 of the same stimulus, but whether the additional thirty 
 seconds strengthens the eff^ect, whether it merely bal- 
 ances fatigue or whether It lessens the eff^ect through 
 adaptation can not be settled a priori. The length of 
 interval, too, seems to aff^ect results but whether three 
 or five or ten minutes is most conducive to rapid devel- 
 opment of functioning of the conditioned reflex, whether 
 it works alike on all ages of and types of children must 
 be questions merely raised for further investigation. 
 
EXPERIMENTS OF KRASNOGORSKI 89 
 
 Moreover with objective methods one looks for ob- 
 jective results. In very few of Krasnogorski's experi- 
 ments do we have statements as to the number of trials 
 necessary to develop the mechanisms. 
 
 In one instance he states that after sixteen stimula- 
 tions a memory reflex was developed (99, p. SI). No 
 statement is given as to the amount of time between 
 these stimulations. If it was even three minutes, the 
 shortest interval he mentions anywhere, the experiment 
 occupied forty-five minutes. This is a period of such 
 a length that for the young child the amount of fatigue 
 in the later stimulations probably almost balanced their 
 impression value. If the experiment was carried on in 
 two or more sittings fatigue may have been avoided but 
 there is no statement to any such effect. At any rate 
 the results would probably be different if achieved at 
 one sitting or if the series was divided and knowledge of 
 the condition should be made available. 
 
 Throughout Krasnogorski speaks of hearing "analy- 
 sers," motor "analysers," visual "analysers" and their 
 functioning which gives specificity to the conditioned re- 
 flexes. We have seen his physiological explanation of 
 these functioning entities. Need we accept it.^ A less 
 mystical explanation seems to lie in a more natural 
 application of the theory of cerebral reflexes in its 
 essential form. A stimulus is applied to some one sense 
 organ. The excitation passes along neural paths into 
 the brain and irradiates into conjunctive paths. Then 
 a second excitant passes in and irradiates from the 
 taste paths to those of motor type leading out to mus- 
 cular and glandular innervation of the throat, lips and 
 salivary glands. But part of the irradiation from the 
 motor region has sped along the nerves leading towards 
 other centers including the one already stimulated by 
 
90 CHILD BEHAVIOR 
 
 our first excitant. This has been doubly used and has 
 a stronger tendency to function a second time than a 
 nerve conductor strengthened by usage only once. 
 After a number of repetitions this path, this habit or 
 association is strong enough to function immediately 
 when only the one stimulus has been given. This is a 
 conditioned reflex pure and simple, or in terms more 
 clearly psychological it is an association, arbitrarily 
 determined, between some one sense excitant and a mo- 
 tor innervation. This is the simplest type of learning. 
 
 The persistence of the conditioned reflex becomes in 
 psychological terms the retention of the association. 
 Its degenerescence or dissolution becomes unlearning. 
 
 The inhibition of the conditioned reflex is the neural 
 restraint of one reflex by the simultaneously working 
 effect of a second reflex as strong or stronger. 
 
 Where the conditioned reflex has been formed upon 
 the memory of an antecedent stimulation we have again 
 the simple association only here it is the image of the 
 sensation or even probably, in the later part of the ex- 
 periment-series, the sensation of cessation of stimula- 
 tion which is associated with the motor cortical center. 
 May it be supposed that if the image functions as the 
 excitant a greater number of applications of the stimu- 
 lus will be necessary, due to the greater vagueness of the 
 image, than in a simultaneous association? May we 
 also assume that if the series needed is not longer the 
 association is rather with the cessation of the stimulus ? 
 
 The mere fact that Krasnogorski finds that the so- 
 called "memory reflex" does develop as easily as the 
 usual co-temporary reflex rather indicates that this 
 suggested interpretation is the correct one. 
 
 The analysers now become the different paths of con- 
 veyance of sense impressions : specificity of reaction 
 
EXPERIMENTS OF KRASNOGORSKI 91 
 
 means sensory discrimination. In the very young child 
 it will be hard for us to tell how far this approaches the 
 physiological limen of sensory discrimination and to 
 what extent it is Seashore's (152) "cognitive" discrimi- 
 nating limen, higher or less fine than the physiological 
 limen due to changes in interest, attention, effort or dis- 
 turbances. In so far as it is dependent upon cognitive 
 abilities one would hesitate before using it, as Krasno- 
 gorski suggests, to map out analgesic or anaesthetic 
 centers unless the mental development of the child has 
 been carefully ascertained beforehand. Moreover the 
 sensory equipment must be examined before we can be 
 sure the cortical mechanisms are getting the proper 
 sensations to differentiate. No reference to any such 
 preliminary study is made by Krasnogorski. 
 
 The conditioned inhibition, or as he called it, "lad- 
 ing and discharge," may be explained as a neural as- 
 sociation with an additional link in it. The cutaneous 
 stimulation, for example, functions through no direct 
 path to the motor center but is associated with an audi- 
 tory excitation and the auditory excitation arouses 
 the motor response. Neither one functions alone be- 
 cause in all probability it is the reception of an audi- 
 tory stimulation by the organism when in a certain at- 
 titude produced by the cutaneous stimulation plus the 
 memory of stimuli, i. e., a state of active attention, 
 which makes the auditory stimulus a sufficient excitant 
 of the reaction. Can this be shown objectively.? 
 
 Thus we see instead of a series of new "mechanisms" 
 merely the objectively studied results of a behaving 
 organism. The Pavlov and Krasnogorski reflexes must, 
 as Hough (83) has pointed out, be differentiated from 
 the unconditioned reflex as a separate type of reaction 
 and not be considered merely as an unconditioned reflex 
 
92 CHILD BEHAVIOR 
 
 in process of formation. The conditioned reflex is 
 learning, association, habit formation. As such the 
 possibility of its formation is a so-called conscious 
 one, functioning through the cerebrum and by means 
 of the so-called association centers. 
 
 The validity of this assumption of the conditioned re- 
 flex as a functioning of the neencephalon is confirmed 
 by Burnett's (22) work on the decerebrate frog, which 
 he found could not learn to escape a labyrinth but per- 
 formed unconditioned reflex acts. 
 
 The observations of Edinger and Fischer (42) re- 
 garding the anencephalic child who lived a purely vege- 
 tative existence for three and a half years but never 
 showed any learning ability again corroborate, and in 
 a more striking way, the same interpretation of the 
 conditioned reflex. 
 
 To what extent we may class the formation of a con- 
 ditioned reflex in the same group of mental processes 
 as the verbal associations it is difficult to state. In 
 the verbal association the stimulus may be the same as 
 in the conditional reflex, may vary similiarly in intensi- 
 ty and complexity, may be just as clearly or indefinitely 
 sensed, causing the verbal reaction which outwardly dif- 
 fers from the feeding reactions only in that it involves 
 more varied motor adjustments which are not so fully 
 developed at birth. 
 
 The conditioned reflexes as we commonly conceive 
 of them are undoubtedly more direct, and have fewer in- 
 termediate steps in their development but how many 
 less and the relative amount of functioning necessary to 
 form an association of either type can only be deter- 
 mined by further experimentation. 
 
 The claims made by Krasnogorski for his method 
 and findings are so great that a verification or disproof 
 
EXPERIMENTS OF KRASNOGORSKI 93 
 
 of them seems to be demanded from the standpoint of 
 both experimental and clinical psychology. If the 
 method is so easily and accurately applicable and al- 
 lows of so many variations, it opens up to the experi- 
 mentalist a most promising avenue of attack upon the 
 infant mind. If it differentiates with such accuracy 
 the defective and pathogenic child while he is still young 
 enough for preventive education and corrective therapy 
 to have a chance, it will revolutionize our present clini- 
 cal methods. 
 
CHAPTER V 
 
 METHODOLOGY AND TECHNIQUE MODIFIED 
 FROM KRASNOGORSKI 
 
 SINCE an extensive and at the same time intensive 
 study of all the processes outlined by Krasno- 
 gorski would involve a problem too voluminous to be 
 handled with facility and coherence, the selection for 
 preliminary study of the processes which seemed most 
 significant became necessary. As the formation of the 
 conditioned reflex is basal to all the other mechanisms, 
 it, naturally, would be included in any group selected. 
 Then, as the fatigue incident upon the development of 
 the conditioned reflex would be apt to interfere with 
 the successful development of any other mechanism, 
 the further experimentation with any one child was 
 postponed until the following day. But it then be- 
 came necessary to ascertain the retained functioning 
 ability of the conditioned reflex after the twenty-four 
 hour interval and this consequently was a test of 
 memorial regression or saving through retention of 
 the learning of the previous day. 
 
 With only these two processes in mind, after some 
 practice experimentation upon available babies, seven 
 idiots at the Massachusetts School for the Feeble- 
 Minded, located at Waverly, were studied. Due to in- 
 teresting diff^erences in functioning of the reflex after 
 the 24-hour period, 48-, 72- and 96-hour intervals were 
 also tried. No apparatus was used for recording 
 the mouth opening and swallowings but the movements 
 
 94 
 
METHODOLOGY AND TECHNIQUE 95 
 
 were observed and immediately recorded by the experi- 
 menter who felt in this series that her mechanization of 
 the procedure of the experiment was not sufficient to 
 enable her to handle with ease the apparatus as well as 
 the child and the food. 
 
 The results obtained by this series of experiments 
 will be discussed in their proper connection later. 
 
 Next, in order that the acquaintance with the use of 
 Krasnogorski's work might not be in one direction only, 
 a long series of observations was made upon one child. 
 This was a boy of five who lived near enough to the 
 laboratory to be able to come regularly, in spite of bad 
 weather, and whose parents recognized, because of their 
 own University training, the value of such studies and 
 gave hearty co-operation. Recording apparatus was 
 used with this child throughout the series. 
 
 The results obtained here showed the need for ex- 
 tensive study of each process to determine the signifi- 
 cance of variations in its functioning as well as to de- 
 termine the probable variations among children of dif- 
 ferent ages, abilities and capacities. Consequently it 
 was decided that the best method of attack was the 
 study of a few of the processes upon a large unselected 
 group of children. 
 
 The processes finally selected for study in the large 
 group of children were the following : 
 
 First, the formation of a simple conditioned reflex, 
 or, in other terms, the formation of a sensory-motor 
 association. 
 
 The Pavlov school has shown that any stimulus may 
 be made the effective stimulus for the functioning of a 
 reflex naturally conditioned by some other stimulus. 
 Such a stimulus should be as little offensive as possible 
 unless we are interested in a comparative study of 
 
96 CHILD BEHAVIOR 
 
 pleasant and unpleasant stimuli, and it should be as 
 simple a stimulus as possible so that the response in 
 different children may not be due to response to differ- 
 ent parts of a complex stimulus. 
 
 Krasnogorski usually used cutaneous or auditory 
 stimuli with the child lying blindfolded. Of course, one 
 rather naturally reasons that with the child, as with 
 an adult, the position and the bandaged eyes would 
 soon suffice to develope an Einstellung of expectation of 
 being fed. But it is highly probable that these factors 
 remained constant throughout the experiment and the 
 condition persisting through periods of non-feeding 
 soon lost whatever stimulating power it may have had, 
 except that it possibly functioned as a stimulus arous- 
 ing a state of expectation or alertness. 
 
 One question presents itself, however. The author 
 tried this method with the first three children studied. 
 Case A was a defective child, almost idiotic and five 
 years old. He allowed the bandage to stay on five 
 minutes, then began to fuss and tear at it. His hands 
 were held down by the nurse, attendant on him, until 
 the third feeding was made at the end of 6' 15'' but 
 even that did not distract his attention and he began 
 crying in earnest and stopped only when the bandage 
 was removed. 
 
 Case B was a five-year-old normal child. He was 
 told to "lie there quietly" and *Vait a little while," 
 when after the second feeding he began pulling at the 
 bandage. This kept him from fussing for two minutes 
 then he announced he didn't "want to stay there any 
 longer." 
 
 Case C was a normal child of fifteen months and she 
 cried violently and tried to take the bandage off as 
 soon as she had finished tasting the first bit of sweet 
 
METHODOLOGY AND TECHNIQUE 97 
 
 chocolate given as the stimulus. 
 
 Krasnogorski himself observed in his earlier work 
 that crying interfered with the conditioned reflex and 
 that renewed experimentation should be delayed until 
 the child was once more quiet. This statement may ac- 
 count for some of the prolonged intervals (25 min., 15 
 min., etc.) that he mentions in his later articles. But 
 from another point of view how much better it would 
 be to avoid entirely any such emotional change and the 
 consequent uncertain but probable modifications in the 
 development of the conditioned reflex. This can easily 
 be done by making the application of the bandage itself 
 the conditioning stimulus. The interval between ex- 
 citations is then a so-called "filled" one and may be 
 devoted to play or to other experiments with the same 
 child. 
 
 This method was the one used in all experiments re- 
 ported in this study. The bandage was applied by 
 gently sliding it down over the child's eyes from above, 
 with a slight but firm pressure of one finger over each 
 eye, thus inducing the most certain exclusion of light 
 and then the bandage was kept in place SO". In the 
 eleventh second the child was fed a bit of sweet cho- 
 colate and the bandage was removed at the end of 
 the twentieth second. Then the child was allowed to 
 sit up and was kept busy with other tests for the in- 
 terval that must elapse before the process was re- 
 peated. The lying down was itself kept from becom- 
 ing the conditioning stimulus by frequently lying the 
 child down in the intervals between experiments. The 
 three-minute interval was used. That is, it was three 
 minutes from the initiation of any one stimulation until 
 the beginning of the next stimulation. 
 
 Several factors determined the choice of these time 
 
98 CHILD BEHAVIOR 
 
 intervals. Ten seconds is the least period of excita- 
 tion used by Krasnogorski and it seemed well to use 
 a period that would give a basis of direct comparison 
 with some of his work. This shortest period was cho- 
 sen because of the probability that a finer, more ex- 
 tensive series of numerical results could be obtained 
 (in terms of the number of applications of stimulus 
 necessary to evoke response) if the stimulus were less 
 and hence less effective in any one application. 
 
 The three-minute interval was chosen instead of the 
 five-, ten- or twenty-minute interval in order to expe- 
 dite the development of the association. Probably here, 
 too, a finer gradation in number of trials necessary to 
 obtain a positive reaction would have been obtained if 
 a longer interval had been used but this consideration 
 seemed outweighed by the following factors: 
 
 1. The need of finishing each day's work with the 
 child before fatigue was sufficient to play an important 
 role in results obtained. 
 
 2. The need of finishing the work with each child in 
 a small enough number of days so that he would not 
 lose interest in the general situation. 
 
 3. The need of developing any standards that might 
 be evolved in an expeditious procedure which would be 
 short, direct, specific enough for clinical use in case 
 Krasnogorski's claims of the diagnostic value of the 
 method were confirmed. 
 
 The average length of time a child was to be used 
 was set at one-half hour. This allowed for the initial 
 procedure and ten repetitions if that number proved 
 necessary. In case more were needed the procedure 
 was continued at twenty-four-hour intervals until the 
 desired result was obtained. The child was considered 
 to have learned to associate the bandage with the feed- 
 
METHODOLOGY AND TECHNIQUE 99 
 
 ing of chocolate when he twice in succession opened his 
 mouth for the chocolate before the ten seconds preced- 
 ing the stimulation by chocolate had elapsed. 
 
 It was felt necessary to use the two responses because 
 sometimes one response might be observed and record- 
 ed and considered an opening of the mouth in antici- 
 pation of food when it was really a slight yawn, a 
 cough, a deep breath, or a laugh. 
 
 The appearance of two consecutive positive reac- 
 tions ended the work for that day. 
 
 Twenty-four hours later the second process was car- 
 ried out. This was the memorial functioning of the 
 association and it was proposed that it be tested by 
 the Ersparnis Methode — calculating the number of 
 trials less than the number used in developing the asso- 
 ciation that were necessary to cause it to function in 
 the same manner. Unfortunately any one memory in- 
 terval chosen arbitrarily is not apt to be the most effi- 
 cient interval. The twenty-four-hour interval was one 
 that had best claims for investigation, however, from 
 our standpoint. It allowed, as do any of the day in- 
 tervals in contrast to the part-day intervals, a second 
 experimentation with the child under conditions of 
 feeding, rest, and play most nearly approximating 
 those of the previous work. It also is an interval short 
 enough to be used possibly in the clinical study of 
 children, and, as the difficulty of getting children who 
 are not under one's immediate control seemingly dou- 
 bles with every additional day over which the experi- 
 mentation must extend, it seemed practically worth 
 studying. Moreover, it may allow for some compari- 
 sons with recalls of reagents on other problems where 
 the interval of delayed recall most frequently used is 
 one of twenty-four hours. 
 
100 CHILD BEHAVIOR 
 
 As soon as the associative functioning was re-estab- 
 lished in the child the third process was begun. This 
 is what Krasnogorski called the inhibition and degencr- 
 escence of the conditioned reflex. The bandage was 
 placed over the child's eyes just the same as when the 
 association was developed but this time the child was 
 not fed. This was repeated until the anticipatory 
 mouth openings and swallowings were entirely absent 
 in two successive trials. The association was then con- 
 sidered to be inhibited or unlearned to a point below 
 the functioning level. From an objective standpoint 
 we can not say whether it was really an inhibition that 
 was developed or merely a fading out of the association 
 previously formed, but the term "unlearning" indicates 
 merely the absence of a response while the term "in- 
 hibition" more frequently means the restraining action 
 of an additional, newly-introduced factor, so it seems 
 better to leave the latter term to be applied to the more 
 complex Krasnogorski process described in Chapter 
 IV, and to designate the third process used in this study 
 as "unlearning." 
 
 The number of trials necessary to effect the unlearn- 
 ing were in some cases too many to allow of full de- 
 velopment in half an hour. The question arose 
 whether here as on the learning process the work should 
 be suspended until the next day and after due con- 
 sideration was answered in the negative. Here we 
 are dealing with a process more apt to be unpleasant 
 to the child than pleasant. In the learning he has been 
 fed every time with a bit of chocolate and learned to 
 expect it, here he expects it and doesn't get it. The 
 probabilities were that if taken home in that state he 
 would be apt to refuse to come back the next day and 
 the work would remain unfinished. Also there was the 
 
METHODOLOGY AND TECHNIQUE 101 
 
 probability that the effect of the partially effected 
 unlearning might be strengthened in some and weakened 
 in others during the twenty-four-hour interval so that 
 we would have to deal with an unknown factor in evalu- 
 ating our results. 
 
 Feeling that these considerations were sufficiently im- 
 portant to make it worth while risking fatigue the ex- 
 periments were continued until the desired results were 
 obtained, although every effort was made through va- 
 ried plays and games and story-telling to decrease the 
 fatigue factor as far as possible. 
 
 For a test of reassociation, the fourth process 
 studied, immediately after a three-minute interval had 
 elapsed after the completion of the unlearning, the 
 stimulus was repeated but this time the child was fed. 
 This was repeated until he again reacted positively 
 twice in succession. 
 
 A saving of several trials was effected in the follow- 
 ing manner : The first time the conditioned reflex func- 
 tioned when it was being memorially tested on the sec- 
 ond day the child was of course fed but when on a 
 successive trial it functioned similarly the child was 
 not fed. Thus although the trial gave us our positive 
 reaction indicating that the association functioned, yet 
 it also became the first in our series of trials for un- 
 learning. Likewise the second of two successive trials 
 indicating complete unlearning was used as the first 
 of the series to correct the unlearning by giving the 
 chocolate. Also, no preliminary record was considered 
 necessary as indicating the quiescent state of the child 
 other than the foreperiod of the first actual trial. 
 
 With this procedure carefully carried out one has 
 a quantitive expression of the ability of the individual 
 (a) in associative learning, the more rapid the learn- 
 
lOS CHILD BEHAVIOR 
 
 ing the fewer the number of trials required; (b) in 
 memory or forgetting, the fewer the number of trials 
 the greater the retention; (c) of the inhibitory effect 
 of a change in conditions and hence of unlearning or 
 adaptability, the adaptation being greater the fewer 
 the number of trials required; and (d) re-association or 
 re-learning, this being less difficult the fewer the num- 
 ber of trials required. 
 
 The objective method of recording used was a 
 slightly modified form of that described by Krasnogor- 
 ski. A small receptive disc of a Marey tambour, at- 
 tached to a long rubber tube, was placed under the 
 hyoid bone and over the thyroid cartilage. This disc 
 passed through a slit in a strip of linen and was held 
 in place by this strip being wrapped around the child's 
 neck. The rubber tube connected with a recording disc 
 which recorded all the movements of the throat and 
 lower jaw upon a kymograph. This recording appara- 
 tus was kept in place throughout the experiment, a pro- 
 cedure rendered feasible by having the rubber tubing 
 plenty long enough to allow the child free movement 
 without his disturbing the adjustment of the record- 
 ing end. 
 
 The time was likewise recorded on the kymograph by 
 a Jacquet chronometer and an electric indicator con- 
 trolled by a telegraph key made it possible to record 
 the actual moment in which the food stimulus was 
 given, as well as the presentation of other stimuli. 
 
 Another point that had to be considered was the 
 method of handling the child himself. This method 
 begins logically with the manner of handling the com- 
 munity in order to obtain permission to use the children. 
 A wrong attitude developed in the parent may not al- 
 ways bring a refusal of the use of the child but may 
 
METHODOLOGY AND TECHNIQUE 103 
 
 instead bring such comment and criticism within the 
 family that the child feels the attitude and reacts ac- 
 cordingly towards the experimenter. 
 
 Of course with the low grade defectives there was 
 little trouble. They were under institutional care and 
 consent was readily given by Dr. Fernald when per- 
 mission to use them was asked. They themselves were 
 too low-grade to seem much influenced by even the pet- 
 ting and caresses of their nurses and being in an insti- 
 tution were accustomed to the presence of little-known 
 faces. Care was taken to visit and study all of them, 
 though, before experimenting began and with the two 
 of highest grade quite a play intimacy was developed. 
 
 With the normal boy Partil who was used for some 
 time the intimacy was developed through two trips to 
 his home before he was asked to go to the laboratory, 
 but there he made up readily and consented at once 
 to come, although his parents thought this a little un- 
 usual as he was rather timid. That the relation was 
 perfectly normal is shown by the fact that the second 
 time I called at his home he was taking a nap and on 
 awakening and hearing that I was there he brought his 
 shoes and suit in and asked me to help him put them 
 on and button the buttons. 
 
 In the attempt to use a large group of children from 
 average homes the situation is somewhat more difficult. 
 Consequently the experimenter studied first of all the 
 village habits and conditions before attempting to gain 
 permission to use the children. 
 
 The work was done in a village of about 400 inhabi- 
 tants. (1910 census says 241.) The village is subur- 
 ban to one of our large eastern cities and has splendid 
 railroad service, rendering the metropolis easily access- 
 ible for business and recreation. It is also on a State 
 
104 CHILD BEHAVIOR 
 
 Road which gives rise to heavy automobile traffic and 
 makes possible a goodly amount of automobile trade. 
 It has a community composed of a large percentage of 
 professional men, commuting to the city, a still larger 
 group of railroad employees of middle scale — engineers, 
 conductors, electrical staff, etc., due to the village be- 
 ing the terminal for all suburban trains, and a new 
 and growing percentage engaged in cement-block mak- 
 ing. Besides these there is a group of some twenty to 
 forty men employed by the leading business concern 
 of the place, a wholesale and retail flour, feed and lum- 
 ber mill and coal yard. The most significant fact per- 
 haps is that there are in a literal sense no dependents 
 in the community. Some years ago a number of good 
 ladies of the place organized a Dorcas Society and 
 sewed for the poor, only to find that there were no poor 
 to accept the garments when they were made. 
 
 Of course there are those who are poor, but as each 
 little house usually has its own garden and as almost 
 every one keeps a few chickens, smaller wages suffice 
 and the independence and frugality of these poor not 
 only makes charity impossible but also shows that they 
 are normal individuals even if not well to do. 
 
 No one group, or social level, was used in this experi- 
 ment but re-agents were drawn from all as far as pos- 
 sible. A couple of rooms near the center of the vil- 
 lage were rented and starting with children nearest 
 at hand they were sought in an ever-widening circle 
 until practically all resources were exhausted. Here 
 and there a child was skipped because he was away 
 when that part of the village was covered or because 
 he lived so far away from all other children as to make 
 the trip, proportionately to the need of using him, 
 rather a proceeding not worth while. 
 
METHODOLOGY AND TECHNIQUE 105 
 
 The majority of the people dwelling there were 
 known, at least by name, to the experimenter and 
 through them the rest were easily met or in many in- 
 stances self-introduction worked informally and well. 
 
 The experimenter studied first of all the village hab- 
 its. Like true German housewives, since they lived in 
 a community where German traditions if not German 
 blood flourished, the morning hours were busy ones for 
 the most. Housekeeping, cooking, gardening, cleaning, 
 washing, made morning calls unsolicited and painfully 
 formal. Early afternoon meant children and many 
 mothers napping, but about four o'clock the broad 
 porches and big or little lawns were in general use. 
 Neighborly chats and semi-social trips to the grocery 
 store or for the mail showed the village as a place full 
 of real live people, but as most of them were financially 
 situated so that they did their own cooking, they were 
 not apt to be far away for a long time, for the man 
 of the house here receives due consideration of his la- 
 bours and needs. In the evening coolness the whole 
 little family was apt to jaunt out to some farther point 
 — the moving picture, the lanes lined with berry bushes 
 or the neighboring, more metropolitan, village. 
 
 Consequently the time between four and six, not too 
 near six, was chosen as the time to solicit the loan of 
 children. Beginning with the children of the "best citi- 
 zen" was avoided. Instead I chose to ask the wife of 
 the chauffeur of one of the best citizens to lend me her 
 three babies. The fact that I'd take them all at once, 
 for a whole morning, two days in succession, appealed 
 to her gossip-loving, care-hating mind, and she con- 
 sented. By the next morning the news of the choice as 
 well as the fact that I had asked her to help me get a 
 complete list of other children was over the whole vil- 
 
106 CHILD BEHAVIOR 
 
 lage "circle," for which she helped set the pace. Dur- 
 ing the two days I used these children I visited other 
 parents in that section, securing their consent and let- 
 ting them name any two days that suited them best, 
 explaining with emphasis the importance of the sec- 
 ond day, and getting acquainted with the children. 
 This was not difficult. The news of toys and games 
 and of pennies to spend for candy before one came home 
 scored every time. 
 
 Whenever there were two or three children under 
 eight in the family I tried to use them the same da3^s 
 and, if there were only one or two, other children whom 
 they knew were taken the same days. I found I could 
 handle three in a morning and this number was the 
 most satisfactory. If I had only two, one was left 
 to play alone while the other was being used. If there 
 were three, two played together, although if they were 
 very young I had a young girl come to assist by taking 
 care of them. If more than three were used the ex- 
 periments ran too near breakfast period on one ex- 
 treme, and too near lunch time on the other, so that 
 satiety and hunger in more extreme forms were intro- 
 duced. 
 
 Calling for the children myself gave me a chance to 
 get acquainted with them more fully while on the way 
 to "my house." Once there, on all pleasant days the 
 children helped take the playthings out on to a large 
 shady corner porch connected by a glass door with the 
 room used for experimenting. In bad weather they 
 played in an adjoining room. Sometimes an older sis- 
 ter came along. This usually simplified matters but the 
 permission was always offered as a great privilege and 
 was naturally always so regarded. 
 
 Then the children usually wandered around in the 
 
METHODOLOGY AND TECHNIQUE 107 
 
 room while I put up windows, smoked the kymograph 
 paper, wound up the kymograph, etc., and prepared 
 record sheets. They usually asked what the kymo- 
 graph was — what it was for, and even if they didn't 
 I always explained — explained so as to form an asso- 
 ciation fully dissociating its slight noise from the main 
 experiment — that I ran it to make the room cooler and 
 keep flies and mosquitos out. Then I allowed it to run 
 so that they would become accustomed to the noise. 
 The rest of the apparatus was never taboo — any ques- 
 tions and curiosity were eliminated before we began 
 experimenting. 
 
 The next question was how to attack the work itself. 
 Here a consideration of the fundamental nature of 
 the child gives us as an attribute most likely to form 
 an adequate basis for handling him, his instinctive love 
 for play. So our whole procedure became a game. The 
 children were told that I wanted to play something with 
 each one alone and so I'd take Marie first and then 
 James. The others could play house, tea party or 
 what they wished on the porch. Schmitt also recog- 
 nizes this for she writes: "With him (the child) the mo- 
 tive most conducive to natural reaction, uncomplicated 
 by disturbing emotions, is the play motive" (149, p. 
 13). Two factors had to be watched, however. The 
 toys must not be given in such profusion as to make 
 a child lose all interest in what might be going on in- 
 doors and the play indoors must be made sufficiently 
 attractive to make him eager to come back a second 
 day. 
 
 The chocolate stimulus itself was quite effective in 
 this way and then if there were any things a particu- 
 lar child disliked in the secondary tests they were left 
 until the second day. Also on our way home we usually 
 
108 CHILD BEHAVIOR 
 
 stopped at the corner drug store and each youngster 
 had an ice cream cone. By the time he had finished 
 this he was home and the recollections of any unpleas- 
 ant details of fatigue were lost in the anticipation of 
 another such treat. Also the fact that I treated their 
 children in such an unnecessary fashion made many 
 of the mothers consider themselves under more heavy 
 obligation to let me have the children the second day. 
 
 The most conclusive proof I can state to the effect 
 that what extra trouble there was was worth while is 
 that no mother refused to let me borrow her children, 
 although in one case the father had to be consulted 
 before she'd say yes. Moreover, of all the children 
 tested one day, none failed to come the second day 
 except one little boy that I refused to take because he 
 was ill. The rest all wanted to come back again, of- 
 fering to come with other children, to help me, to put 
 the toys away or even in several instances declaring 
 they wanted to come and live with me. 
 
 During the two-and-a-half-minute intervals in all of 
 these processes a definite procedure was followed. Bit 
 by bit the Binet tests and those additional tests neces- 
 sary for the Point Scale evaluation, were given. The 
 Healy Construction Puzzles A and B, the Healy Foal 
 and Mare and School Puzzles, the Goddard Adaptation 
 Board, and Goddard modification of the Seguin Form 
 Board were also used. Also each child was measured 
 for standing and sitting height, weight, dynamometer 
 measurement of grip with the right and left hand and 
 lung capacity as measured by the wet spirometer. 
 
 The intelligence of the parents was also rather point- 
 edly observed during the visits to the homes, which 
 also gave significant facts regarding each child's en- 
 vironment. These estimations of intelligence of the pa- 
 
METHODOLOGY AND TECHNIQUE 109 
 
 rents as average or not were corroborated by appeal 
 to the family physician of the village, and in still 
 doubtful instances by appeal to the leading business 
 man of the village who was in financial touch with prac- 
 tically all of them. 
 
 One requirement that is harder to fulfill when work- 
 ing with children than it is when working with adults 
 is that of uniform verbal Aufgabe. Even though the 
 task itself may be uniformly explained or directed the 
 child cannot and does not (nor need he) understand the 
 purpose as even an untrained adult does. He asks 
 questions and they must be answered; he raises objec- 
 tions, they must be met; he modifies his procedure to 
 suit his own pleasure. The control of all this must 
 not be one of forcing into a narrow and fixed groove 
 all responses so that they may be used but in a quick 
 adaptation of non-essentials which £re kept before the 
 child while the process under observation is tested un- 
 der unmodified conditions. One may have to pet, coax, 
 bribe, or even with some children threaten a little but 
 I write this last word rather hesitatingly. In most 
 children threatening of any sort upsets the normal 
 poise. Now and then one finds, however, the child 
 who may be threatened by the idea of how badly he 
 would feel if he failed, if some one else, a concrete per- 
 son, did better than he. Or one finds the child who 
 may need to be told that we won't need him unless he 
 tries harder. But usually the work should be held 
 as a privilege and open choice on the material or ac- 
 tivity to fill the rest intervals will lead the child to 
 feel he is perfectly free in the whole procedure. One 
 of the chief advantages of this method of conditioned 
 reflexes is its utter lack of any need for verbal direc- 
 tions, the child formulates for himself his response to 
 
110 CHILD BEHAVIOR 
 
 a situation. 
 
 Besides the kymograph record of the movements, the 
 observed movements not only of mouth and throat but 
 of the whole body, any unusual disturbance and any 
 verbal or behavior reactions were noted immediately 
 after each trial. 
 
 The extra tests, which consisted of all the more gen- 
 erally used clinic tests for mental diagnosis that are 
 applicable with such young subjects, were given in a 
 standard way, the one adapted by the experimenter 
 after five years of experience with such tests. 
 
 In using the Binet Scale the Goddard (58, 60, 62) 
 Revision was used throughout and supplemented, as 
 is done in the Vineland Laboratory and the Massachu- 
 setts School for Feeble-Minded, by the Binet-Simon 
 series of six easier tests for idiots (57). 
 
 The Point Scale was used as accurately as possible 
 according to directions given in the article in print 
 at that time (190), as the Yerkes-Bridges (191) book 
 on the Scale had not then been issued from the press. 
 Where the questions in the Binet and the Point Scale 
 were similar but varied in difficulty of presentation, the 
 more difficult form was given first and if that failed 
 the less difficult method was used, credit being given 
 accordingly. 
 
 The Healy Boards were all four presented to the 
 child one after another with the directions suggested by 
 Healy and Fernald (75). Minute records were not 
 made of the errors but merely a record of the total 
 length of time and the type of procedure, although if 
 Schmitt's (149) standardization had appeared before 
 the experiments had been made I would undoubtedly 
 have followed her suggestion and recorded the time 
 on the triangles in the Foal and Mare Puzzle sepa- 
 
METHODOLOGY AND TECHNIQUE 111 
 
 rately. 
 
 The Adaptation Board was used as Goddard (63) 
 suggests but with these modifications and additions. 
 Due to the brief, indirect directions given it may be 
 possible that a child fails on the first turn because of 
 lack of or rather misdirected attention. Hence, if a 
 child failed on the first trial but succeeded on the sec- 
 ond, another trial was given on the turn from lower 
 left to lower right. Then several new moves were also 
 added to the board's use. These are ones suggested 
 but not standardized by Goddard (63, p. 188). The 
 third turn, or first added turn, was from lower left to 
 lower right and on to upper right without stopping. 
 The fourth turn was from upper right to upper left to 
 lower left to lower right without stopping. These ad- 
 ditions allow of a wider use of the test and finer gra- 
 dation of ability. 
 
 The Form Board was used as Goddard (61) and Syl- 
 vester (168) suggest. It was given three times the 
 first day and, on the last nineteen children, three times 
 on the second day. This usage on the second day sug- 
 gested itself at that point as another corroboration of 
 the memorial regression of learning. This board, as 
 well as all other of the tests were presented to all the 
 children used, regardless of any doubts the experi- 
 menter had, due to the age of the child, as to its ability 
 to perform the required tasks. The time was recorded 
 with a stop-watch and the child urged to hurry and 
 make speed a part of his goal-idea. 
 
 Height standing and sitting were measured in milli- 
 meters and expressed to the nearest centimeter. 
 
 Weight was measured in kilograms to the nearest 
 tenth. 
 
 Grip was measured in kilograms to the nearest tenth 
 
112 ! CHILD BEHAVIOR 
 
 upon an adjustable Smedley dynamometer. 
 
 Lung capacity was measured by the wet spirometer 
 and expressed in liters to the nearest hundredth. 
 
 With exactly the same procedure another group of 
 such children as tested normal or nearly so by the Binet 
 and performance tests but who were, because of hered- 
 ity or a-social reactions, suspected of mental defect 
 was studied. These children, seven in number, were 
 inmates or observation cases at the Massachusetts State 
 School for the Feeble-Minded. 
 
 Also, two children were accessible who had been clini- 
 cally studied and diagnosed as not feeble-minded but 
 as "normal on all tests." These children had been taken 
 to the clinic because of suspected defect due to lack 
 of ability to get along in school. 
 
CHAPTER VI 
 
 PRELIMINARY EXPERIMENTS AND THEIR 
 INDICATIONS 
 
 THE preliminary investigation of the use of Kras- 
 nogorski's method was twofold. First a study 
 was made of seven young defective children who were 
 available. It seemed feasible that a method whch could 
 be applied with definite results upon such low-grade 
 children would be applicable without difficulty upon 
 normal children; also, if Krasnogorski's statements 
 were true, the conditioned reflexes would here be ob- 
 tained only with greater difficulty than upon normals 
 and hence their development would allow more experi- 
 mentation with the method itself. 
 
 Secondly, an extensive study was made of one child, 
 endeavoring to develop a number of the various mechan- 
 isms, but here again primarily with the aim of study- 
 ing and understanding the method. 
 
 The work upon the seven low-grade defectives in- 
 volved two processes, learning and forgetting. 
 
 Although the method used with this group varied 
 somewhat from individual to individual, due to the fact 
 that the procedure was one arbitrarily determined yet 
 the results seem worth presenting in detail, chiefly be- 
 cause they form the basis for the definite procedure 
 followed upon the larger group of children used in the 
 later experiments. 
 
 The plan begun with was to leave the child lying 
 113 
 
114 CHILD BEHAVIOR 
 
 on a low couch (all but two of the seven studied spent 
 their whole day lying down or tied in a chair) and to 
 apply the bandage as previously described. Then after 
 5 seconds to stimulate the right arm above the elbow 
 for 10 seconds and in the sixteenth second to feed a bit 
 of sweet chocolate, to be exact, a piece one centimeter 
 square. 
 
 The first modification came in the food stimulus. 
 Three of the seven children refused to eat candy and 
 were accustomed to liquid foods only. This fact was 
 ascertained beforehand. Each was then experimen- 
 tally fed a bit of chocolate and when it was definitely 
 refused a new stimulus, sweetened water, was adopted. 
 Two of them took this readily from a spoon but the 
 third refused this when made from white sugar and 
 took it only when it was made from brown sugar to 
 which he had become accustomed. It was thought bet- 
 ter to use this rather than honey, which was used by 
 Krasnogorski, as honey is not only an unknown taste 
 quality to some children and not always liked when 
 first tasted, but the use of it is apt to lead rapidly to 
 a feeling of satiety, at least such is the report of a 
 number of older persons, and our stimulus should be 
 just sufficient to evoke with the sensation a pleasant 
 affective toning making the subject desirous of more. 
 
 The next modification was that regarding the use of 
 the bandage. It seemed highly probable that these de- 
 fective children were so low grade that they might 
 easily be persuaded to lie with the bandage over their 
 eyes throughout the experiment. Experience proved 
 the opposite. Their negative reaction to the bandage, 
 if violence of behavior be a just criterion, was far 
 greater than their positive reaction to the sweet fed 
 to them. Two of them cried out at first when the 
 
PRELIMINARY EXPERIMENTS 115 
 
 bandage was put on and all of the others, even the 
 very lowest grade ones, tried to get it off after they 
 had been fed and lain a little while. 
 
 Since the difference in reactions is marked in a quali- 
 tative as well as a quantitative manner it seems best to 
 describe the results by the individual cases. 
 
 1. Leitha was a little girl, aged 55 months, born in 
 this country of English parentage. Peculiarity mani- 
 fested itself through bumping of the head, crying and 
 convulsive muscular attacks, etc., between the ages of 
 one and two. She walked at 25 months but her gait 
 is still straddling and uncertain. She has so far not 
 formed any habits of cleanliness, does not talk and has 
 to be fed with a spoon. Indeed if she is hungry and 
 food is on the table within reach she does not know 
 enough to take it. She does not seem to recognize the 
 nurses who are with her the whole time. She has been 
 diagnosed as a low-grade idiot with a mentality of less 
 than one year. She has not improved since these ex- 
 periments were made. 
 
 I began trying to develop a conditioned opening of 
 the mouth through excluding light by a bandage with 
 a cutaneous stimulation upon the right arm above the 
 elbow. At first she was rather restless and grew mark- 
 edly so if the bandage was kept on after she was fed 
 and had eaten the candy. Ten trials were given the 
 first day without the slightest indication of an associa- 
 tion having been made. On the next day she lay quiet 
 for the first two trials and on the third trial opened 
 her mouth, grinding her teeth and said "eh-ah" before 
 she was fed. This was repeated the fourth time, so 
 the conditioned association had been developed in 14 
 trials. 
 
 The conditioned reflex was stimulated and functioned 
 
116 ) CHILD BEHAVIOR 
 
 without defect six more times that day, marking 10 
 trials in all, then the child was allowed to rest. The 
 reaction was, however, to the application of the band- 
 age before cutaneous stimulation was applied and so 
 during the rest of the work upon her the bandage alone 
 was used. 
 
 Twenty-four hours later the procedure was repeat- 
 ed. The first trial she was quiet but on the second 
 trial she at once began smiling, making noises and 
 opening her mouth. This happened on three successive 
 trials. 
 
 After another forty-eight hours, when the process 
 was again tried, there was no response upon the first 
 two trials but upon the third trial she opened her 
 mouth after nearly ten seconds of stimulation by the 
 bandage, similarly on the fourth trial, while on the 
 fifth trial she began smacking her lips as soon as the 
 bandage was put over her eyes. 
 
 She was allowed to rest 4 days and then the ex- 
 periment was repeated. The child was not in good 
 condition for the work. She was very restless and con- 
 tinually falling into the masturbating movements char- 
 acteristic of idiots, grinding her teeth at the same time. 
 She seemed, however, to react positively upon the sev- 
 enth trial and this is probably accurate as there was 
 no difficulty in deciding that she had not reacted posi- 
 tively before and as this seeming reaction was present 
 in three succeeding trials. 
 
 Twenty-four hours later six trials were necessary for 
 functioning and this functioning continued through 
 the four succeeding trials given on that day. 
 
 Forty-eight hours later 4 trials brought the re- 
 quired reaction. 
 
 With Leitha, and on the others of this group as 
 
PRELIMINARY EXPERIMENTS 117 
 
 well, an effort was made to keep the number of trials 
 from day to day at either five or ten. This proved 
 disadvantageous and was not tried in any later series. 
 One of the disadvantages is the increased difficulty in 
 calculating the number of trials necessary for memo- 
 rial functioning and saving. To do this we must count 
 all the trials after the proper functioning on a given 
 day and add them to the number required for func- 
 tioning upon the next day in order to get the full 
 series. 
 
 If we do this with the data obtained upon Leitha we 
 have the following results : — 
 
 For Learning the number of trials required is 14. 
 For Memory the number of trials required is 9 after 24 hours. 
 For Memory the number of trials required is 6 after 48 hours. 
 For Memory the number of trials required is 9 after 96 hours. 
 For Memory the number of trials required is 8 after 24 hours. 
 For Memory the number of trials required is 8 after 24 hours. 
 
 If, however, we disregard the trials given after the 
 conditioned reflex functioned on a given day and count 
 only the number of trials necessary to re-establish it 
 the next we have the following number of trials re- 
 quired : 
 
 After an interval, since last functioning, of 24 hrs. — 3 trials were needed 
 After an interval, since last functioning, of 48 hrs. — 4 trials were needed 
 After an interval, since last functioning, of 96 hrs. — 8 trials were needed 
 After an interval, since last functioning, of 24 hrs. — 6 trials were needed 
 After an interval, since last functioning, of 48 hrs. — 4 trials were needed 
 
 These figures vary much more nearly as the time fac- 
 tor, and, although any deduction is merely a surmise, 
 seem to indicate that the habituation of an idiot child 
 to a process newly acquired is not greatly helped by in- 
 creasing the number of times the habit is exercised any 
 
118 CHILD BEHAVIOR 
 
 one day but that functioning at short intervals is more 
 important. This agrees with the conclusions reached 
 by those studying the relative value of grouped a^id dis- 
 tributed repetitions for learning but it is also probable 
 that the effects of fatigue may be more marked here 
 than they would be in normal subjects or adults and 
 so render the last trials on the day of learning rela- 
 tively weak in effect. 
 
 S. Pasha was a boy about 50 months old, born in 
 America of Armenian parentage. He is a helpless di- 
 plegiac, not able to move much. He is not clean, cannot 
 feed himself, seems to be able to understand a few 
 words. Diagnosed as an idiot with a mentality of one 
 year. No improvement since. 
 
 Since he eats only liquid food he was given sweetened 
 water. With him I used bandage on 5", followed by 
 stimulation of upper right arm with camel's hair brush 
 for 10'', then feeding in the sixteenth second. 
 
 He developed the association between bandage and 
 feeding in the fourth trial but from the fifth trial on did 
 not begin reacting until brush touched the arm. 
 
 The results obtained with him were as follows : 
 
 Length of interval since last pre- 
 vious trial 24 hrs. 48 hrs. 96 hrs. 
 
 1st 2nd 
 trial trial 
 
 Number of trials needed on day 
 
 of new trial 3 3 4 2 
 
 Number of trials of over-learn- 
 ing that had been given on the 
 day of last previous trial 4 2 2 1 
 
 Total number of trials needed 
 
 for functioning 7 5 6 3 
 
PRELIMINARY EXPERIMENTS 119 
 
 Learning to associate bandage and feeding took five 
 trials while learning to associate bandage, brushing the 
 arm and food took six trials. The memorial function- 
 ing took a varied number of trials in the different 
 length intervals and even in two different trials after 
 the same length intervals. 
 
 3. Ahil was a boy 51 months old, born in America 
 of Russian parentage. He was a seven-months baby, 
 is spastic in both legs and rather microcephalic. He 
 is unclean and does not feed himself. He has been 
 diagnosed as an idiot with a mentality of between one 
 and two years of age. He showed no signs of improve- 
 ment in the year between the time of the experiments 
 and his death. 
 
 Here, also, an attempt was made to develop the dis- 
 criminating reflex to the cutaneous stimulation. Dur- 
 ing the ten trials on the first day no response to the 
 situation developed but on the second trial the next 
 day the child reached up and tried to pull the bandage 
 off after he was fed. He had not tried to pull it off 
 before. This happened throughout the rest of the 
 trials that day. There was no reaction to the bandage 
 when applied nor to the cutaneous stimulation. 
 
 After twenty-four hours he took the bandage off on 
 the second trial. Two days later he removed it on 
 the first trial, and 4 days later and again after 4 days 
 he removed it upon the first trial. Throughout he 
 showed no other reaction to the situation. After the 
 experiment was finished it seemed advisable to examine 
 his skin sensitivity with the result that we found him 
 almost completely anaesthetic and even analgesic, ex- 
 cept on and around his lips, to such minimal stimuli 
 as were being used in the experiment. The motor re- 
 action of removing the bandage is, however, as good 
 
120 CHILD BEHAVIOR 
 
 as any food reaction for the study of the learning 
 process and shows here the fumbling but sure adjust- 
 ment of even a faulty organism to environmental con- 
 ditions. Summarizing, we see that the association de- 
 veloped in 18 trials while memorial functioning was as 
 follows : 
 
 Length of interval since last 
 
 experiment 24 hrs. 48 hrs. 96 hrs. 
 
 1st 2nd 
 trial trial 
 
 Number of trials needed to es- 
 tablish functioning on day 
 of re-trial 3 2 2 2 
 
 Number of trials of over-learn- 
 ing given on day of previous 
 learning 7 2 3 3 
 
 Total number of trials given 10 4 5 5 
 
 Here again we see that the regularity of the num- 
 ber of trials given at each sitting interferes with a 
 direct study of the number required for actual reten- 
 tion and probably is in excess as the association is 
 found to function in the first two trials after 2- and 4- 
 day intervals since last functioning. 
 
 4. Jorsi is a boy 60 months of age, American born 
 of Italian parents. He is a swarthy youngster covered 
 all over with fine black hair. He is rachitic and the 
 sternum protrudes sharply. He has a slight lumbar 
 scoliosis and enlarged epiphyses of the wrists, elbows, 
 ankles and knees ; has also umbilical hernia and large 
 tonsils and adenoids. He is clean and feeds himself 
 with a spoon. He can walk by pushing against a chair ; 
 plays real nicely and with good coordination with small 
 
PRELIMINARY EXPERIMENTS 121 
 
 objects. Diagnosed as an idiot with a mentality of 
 1 ^ years by the Binet. (No marked improvement be- 
 fore death, which occurred recently.) 
 
 With Jorsi, also, an attempt was made to develop 
 the conditioned reflex to a cutaneous stimulation. At 
 first he gave no reaction except to try to get the band- 
 age off even before the feeding, then on the ninth trial 
 he lay quiet but took the bandage off at once after he 
 was fed. This happened on the tenth trial also. After 
 twenty-four hours he removed the bandage on the sec- 
 ond trial but not until the third trial, or thirteenth in 
 all, did he open his mouth before he was fed. Even 
 then this reflex functioned irregularly, being firmly es- 
 tablished only after the nineteenth trial, although the 
 reaction of removing the bandage functioned regularly 
 after the twelfth trial. 
 
 After another 24 hours he removed the bandage on 
 the first trial but opened his mouth only upon the sec- 
 ond trial. 
 
 Forty-eight hours later both mouth opening and re- 
 moving the bandage came at the correct time in the 
 first trial. One point is to be noted, however. At no 
 time was there any reaction to the cutaneous reaction 
 as distinguished from the application of the bandage. 
 His mouth opened as wide before the brush was applied 
 as after. He was not suff^ering from anaesthesia. 
 
 Considering the development of the association be- 
 tween food and removing bandage we find establishing 
 it took 10 trials, while that between bandage and feed- 
 ing took 14 trials, then functioned irregularly but 
 after 19 trials is fully established. The memorial 
 functioning is as follows, the numbers in parentheses 
 being for bandage-food associations, the other for feed- 
 ing-remove bandage associations: 
 
122 CHILD BEHAVIOR 
 
 Interval since last experiment 24 hrs. 48 hrs. 
 
 No. of trials given on day of re-trial 2 (3) 2 (2) 
 No. of trials of over-learning given 
 
 in previous experiment '^ (^) 3(3) 
 
 Total number of trials used 9 (9) 5 (6) 
 
 Jorsi was sick when the time came for a 96-hour 
 trial of memorial functioning and so was not tested 
 after that interval. 
 
 5. John was a boy about 36 months old, born in 
 America of Italian parentage. He was reported as 
 "peculiar from the time of birth." He has a cleft 
 palate and hare lip but both soft and hard palate have 
 been repaired. He does not walk or talk but feeds 
 himself with a spoon. Is diagnosed as an idiot with 
 a mentality of 1 ^ by Binet and as probably hydro- 
 cephalic. He has since died. No microscopical findings 
 are as yet available upon any of the three who have 
 died but the description of gross physical attributes has 
 not been reversed by the autopsy studies. 
 
 An attempt was made to develop an association be- 
 tween cutaneous stimulation and feeding. On and af- 
 ter the fifth trial he reacted to the application of the 
 bandage by opening his mouth with mouthing and suck- 
 ing movements. After three more trials the mouthing 
 was deferred until the cutaneous stimulation was ap- 
 plied, or the first type of association was formed in 6 
 and the second in 9 trials. 
 
 After twenty-four hours the cutaneous-feeding asso- 
 ciation functioned on the second and successive trials. 
 After another twenty-four hours the cutaneous-feeding 
 association functioned at once. After 48 hours the 
 bandage-feeding association functioned at once but it 
 took five trials to redevelop the cutaneous-feeding asso- 
 
PRELIMINARY EXPERIMENTS 123 
 
 elation. After 96 hours more the cutaneous-feeding 
 association functioned immediately. The results are as 
 follows, figures representing bandage-feeding or band- 
 age-open mouth associations being in parentheses : 
 
 Length of time since last ex- 
 periment 24 hrs. 48 hrs. 96 hrs. 
 
 1st 2nd 
 trial trial 
 
 No. of trials needed on day of 
 
 re-trial 3-2 5 (2) 2 
 
 No. of trials of over-learning 
 
 previously given 1-2 3(3) 
 
 Total number of trials inducing 
 
 the reaction 4-4 8 (5) 2 
 
 6. Jock is a boy 34 months old, American born of 
 American parents. He had convulsions when about 18 
 months old, but probably was not normal before that 
 time. What is known of his parents is not very much 
 in their favor, being merely that they have never lived 
 long enough in any one place to have legal residence 
 there. The child is somewhat undersized, does not 
 talk, is not clean in his habits, learned to walk at two 
 years of age but is rather unsteady in his gait. He 
 feeds himself with a spoon. Is diagnosed as an imbe- 
 cile with a present mentality of about two years. 
 
 The experience with the preceding cases led to a 
 modification of our procedure here. No use was made 
 of the cutaneous stimulation at first but an attempt 
 was made to establish the association between the band- 
 age and feeding, the bandage being kept on ten seconds 
 before the food was given. 
 
 Only five trials were given the first day as Jock rather 
 
lU CHILD BEHAVIOR 
 
 disliked the bandage although he seemed to like the 
 candy. The second day ten more were given but with- 
 out any reaction before the feeding. On the third day 
 he opened his mouth anticipating feeding upon the sec- 
 ond and successive trials, making 18 in all for the learn- 
 ing. Seven more trials were given that day, all with 
 positive reactions, indeed before the last trial, during 
 the play interval, he managed to get possession of my 
 handkerchief, put it on the back of his head and opened 
 his mouth, evidently for candy. 
 
 After 24 hours the association functioned at once 
 and was strengthened throughout five trials. Then in 
 the sixth trial for that day a double procedure was 
 tried. Period a, the bandage was put on 10 seconds, 
 no candy given, and it was taken off. Period b, after 
 5 seconds it was put on again, and cutaneous stimula- 
 tion applied at the same time, candy being given at 
 the end of 10 seconds. 
 
 Immediately after this first trial Jock took another 
 brush with which he had been punching holes into paper 
 and rubbed his own arm. 
 
 In the next trial he stretched out his arm as soon 
 as I put the bandage on and opened his mouth, not dis- 
 criminating periods a and b. This happened in the 
 next trial but in the last two trials of that day he lay 
 absolutely without reaction in both periods. 
 
 After 24* hours he reacted only when touched by 
 the brush in the second and successive trials. In the 
 eighth trial for that day he developed a new reaction. 
 As soon as the bandage was put on he would stretch his 
 arm out towards me, although in stimulating it, it had 
 always been left in its natural position alongside his 
 body, and then after it was touched he would open his 
 mouth. 
 
PRELIMINARY EXPERIMENTS 125 
 
 After twenty-four hours more, when tried again, he 
 was not very well but seemed to want to go through our 
 game, running to me as soon as he saw me coming. Dis- 
 crimination seemed lost as he would open his mouth 
 before as well as after the cutaneous stimulation. His 
 own activity, however, showed that some sort of an 
 association was there, for as he sat playing on the 
 couch he put a handkerchief on his head and tried to 
 rub his hand with a pencil, then wanted me to take it, 
 and, when I did, he lay down and opened his mouth. 
 
 Two days later no reaction was obtained which 
 lacked discrimination and this correct reaction ap- 
 peared also upon presentation of the cutaneous stimu- 
 lation, and to it only, 48 hours after this first 48- 
 hour trial. 
 
 7. George was a boy 73 months old, American bom 
 of French-Canadian parents. He was a seven-months 
 baby, his mother was alcoholic and has since disap- 
 peared, while his father is in a Home of Correction. 
 The child's defect was noticed at one year of age. 
 He began to walk at three years of age. He says a 
 few sounds, feeds himself with a spoon and is clean in 
 his personal habits. Has chronic ringworm of scalp, 
 masturbates, is very nervous and excitable, although 
 usually very good tempered. He talks incessantly in a 
 jargon of his own, tries to imitate sounds but does not 
 attempt a systematic use of even the few words he 
 knows. His coordination of eye and hand is very good, 
 and he seems to notice a great deal in his environment. 
 He has been diagnosed as an imbecile with a present 
 mentality of between two and three years. 
 
 The same method was used with him as with case 6. 
 At first he tried to remove the bandage before he was 
 fed but gradually this activity disappeared and after 8 
 
126 CHILD BEHAVIOR 
 
 trials he had learned to remove it after he was fed 
 but made no attempt to do so before he was fed. Not 
 until the second day did he open his mouth before the 
 feeding, but it developed in the first two trials on that 
 day, taking twelve trials in all, but on the second trial 
 that day he stopped removing the bandage and only 
 re-developed this reaction in connection with opening 
 his mouth upon the fifth and sixth trials of that day. 
 After that the series worked as if automatically. I 
 would place the bandage on his eyes, his mouth would 
 open, I would give the chocolate, his hand would re- 
 move the bandage and then, usually, he would laugh. 
 
 After 24 hours this series functioned once. Then 
 an attempt was made to develop the inhibition of the 
 mouth opening unless the cutaneous stimulus accom- 
 panied the bandage by the procedure of alternation used 
 and described in case 6, Jock. At first he opened his 
 mouth under conditions of both the a and the h periods. 
 On the eighth trial he opened his mouth once when the 
 bandage only was used, then closed it, opened it also in 
 h of that trial and moved his arm as the brush touched 
 it. In trials nine and ten he did not open his mouth 
 for either condition but as he made no attempt to re- 
 move the bandage it seems obvious that he in some way 
 anticipated food. 
 
 On the first trial the next day he opened his mouth 
 in period a and was not fed, then kept it closed for &. 
 On the second trial his reaction was the same. On the 
 third trial he made no response in period a but opened 
 his mouth once in period h. In trials four, five, six and 
 seven he was quiet during period a but opened his mouth 
 during cutaneous stimulation, i. e., period h. This shows 
 beautifully the various stages of development of a dis- 
 crimination or of inhibition to one group of conditions, 
 
PRELIMINARY EXPERIMENTS 19,1 
 
 mentioned by Krasnogorski. But this seeming discrimi- 
 nation might be due to an established rhythm of no 
 response — response, consequently, in the eighth trial the 
 cutaneous stimulus was given at once, a period being 
 omitted, and the correct reaction appeared, while in 
 trials nine and ten the a period was used without evok- 
 ing response which functioned correctly in the b period. 
 
 After 24 hours the reaction was absent from both a 
 and b periods for two trials but re-developed in b in the 
 third trial with the addition that he would stretch out 
 his arm at right angles with his body and say "la-la- 
 na-na" before the cutaneous stimulation began. This 
 occurred regularly during seven succeeding trials given 
 that day. 
 
 After 48 hours there was no response upon a first 
 trial but the series of reactions appeared upon the sec- 
 ond and succeeding trials. On the fourth trial, before 
 it was time, he lay down, tried to put a bandage on his 
 eyes, stretched out his arm and opened his mouth. 
 Forty-eight hours later he repeated this same series of 
 acts as soon as I began working with him. 
 
 This series convinced me that the mechanism of a 
 conditioned reflex or stimulus-reaction association could 
 be easily developed with even young children, but also 
 showed that the conditions were more complex than had 
 been supposed while the variations in details of method 
 loomed up as innumerable. But before attempting to 
 determine just which points would best repay for a 
 quantitative and detailed study, another series of pre- 
 liminary experiments, this time a developmental one, 
 was carried out upon one and the same child. 
 
 Partil was 65 months old when I began working with 
 him. He was unusually well developed physically for 
 his age but very nervous, given to small twitching move- 
 
128 . CHILD BEHAVIOR 
 
 merits of which he seemed unconscious. By the Binet 
 tests he tested 7 ^, accomplishing in all 34 points. On 
 the Bridges-Yerkes he scaled 32 points. He could not 
 do the Healy Construction Puzzles A or B, nor the 
 Foal and Mare Puzzle without help. The School Room 
 Puzzle he succeeded in completing but with the blocks 
 for the window and blackboard spaces interchanged, nor 
 did he notice this error until it was called to his at- 
 tention. He learned rapidly, however, and did all of 
 these without difficulty when given a second trial. 
 
 He had been accustomed to having the bandage of 
 the receptive Marey tambour around his neck while 
 he played in the laboratory and did the various form- 
 boards, also to having the bandage over his eyes at ir- 
 regular intervals while the kymograph and chronome- 
 ter, separated from the couch where he played by a 
 screen, were kept running during the whole fore-period. 
 
 The reaction to cutaneous stimulation with the eyes 
 bandaged was first developed by putting the bandage on 
 and after 5 seconds starting the cutaneous stimulation, 
 then feeding ten seconds later. This conditioned reflex 
 functioned on the fourth and fifth trials. Then work 
 for that day ceased. After M hours the retention 
 value of the association was studied. The first trial 
 found the child very quiet, on the second trial slight 
 twitchings and openings of the mouth were noticed 
 while on the third trial the mouth openings were very 
 marked and breathing was heavy enough to be recorded 
 in the curve of throat and mouth openings. That the 
 child anticipated candy may be seen by his question as 
 to where the candy came from which he answered for 
 himself by associating it with the black kymograph for 
 he said, "Oh, I see, that (the kymograph) turns and it 
 comes out of there (pointing in the top) and you give 
 
PRELIMINARY EXPERIMENTS 129 
 
 it to me." After forty-eight hours the association func- 
 tioned slightly on the first trial and markedly on the 
 second and third trials. Owing to the child's going 
 away for Christmas work stopped at this point and was 
 resumed after an interval of 25 days. 
 
 While I was adjusting the apparatus the first day 
 after this interval Partil said, "I know what that feels 
 like." "What does it feel like.?", I asked. "Chocolate," 
 he answered. "Why".? "I don't know." An attempt 
 was then made to test the functioning strength of the 
 association previously established between the cutane- 
 ous stimulation and the mouth opening. Upon the first 
 trial there was no reaction except slight general move- 
 ments of the body, twitching of the hands, etc. Upon 
 the second trial very definite mouth openings appeared 
 but they appeared in the period before the tactual stim- 
 ulation, immediately after the bandage was adjusted, as 
 well as in the later period. This condition persisted in 
 the third trial. In the fourth trial the reaction 
 occurred during the cutaneous stimulation only. As 
 the child seemed very tired the day's experiments were 
 discontinued at this point. 
 
 After 24 hours the correct reaction occurred upon 
 the first trial. Then an attempt was made to determine 
 specificity or localization for the cutaneous stimulation. 
 So far cutaneous stimulations had always been applied 
 to a definite place, i. e., the inner side of the right arm 
 just above the elbow. Now the same place on the left 
 arm was also stimulated. The stimulus was applied 
 10'' on the left arm, then 10" on the right arm, then 
 the child was fed. The first time there was no reaction 
 except a slight opening of the mouth at the moment of 
 change from the left to the right arm, although 
 throughout the child's body was stiff and tense. 
 
130 CHILD BEHAVIOR 
 
 In the succeeding trials 5'' was allowed to elapse be- 
 tween the stimulation on the left and right arms in 
 order to reduce any shock of change. On the first of 
 these trials there was no reaction except a slight stiffen- 
 ing and extending of the right arm before the brush 
 was applied to it, then a very faint swallowing move- 
 ment after it had been applied about five seconds. On 
 the next or in all the third trial for specificity there was 
 more definite reaction but only to the correct stimula- 
 tion. The indications are that specificity as such, at 
 least right-left specificity had developed with the con- 
 ditioned reflex itself, although all reaction was tem- 
 porarily inhibited by the introduction of the new area 
 of stimulation. 
 
 After 24 hours specificity in reaction occurred in the 
 first trial, then the conditions were complicated even 
 more. The cutaneous stimulus was applied for 10" to 
 the left cheek, with a marked reaction. Then five sec- 
 onds of no cutaneous stimulation intervened during 
 which period the reaction persisted but gradually di- 
 minished, then the right cheek was stimulated for 10'', 
 again with violent reaction, then 5" intermission fol- 
 lowed and finally came 10'' stimulation of the right arm 
 without any reaction except very heavy breathing. In 
 the next trial the same order of stimulation prevailed 
 except that 10" stimulation of the left arm was also 
 introduced between the stimulation on the cheeks and 
 that on the right arm. Reaction was marked to all 
 stimulations applied except to that on the right arm 
 to which there was no reaction. In the next trial the 
 intermissions were omitted to shorten the series and 10" 
 stimulation given on each of the following places — left 
 cheek, forehead, right cheek, left arm, right arm, with- 
 out arousing reaction to any except the new area, i. e., 
 
PRELIMINARY EXPERIMENTS 131 
 
 the forehead. The child now seemed tired, said he 
 wanted to go up stairs and see the toys, so only one 
 more series was tried. This time the same places were 
 stimulated as in the last trial preceding but only S" 
 stimulation on each, except on the right arm where the 
 usual 10" was given. No reaction occurred except to 
 the stimulation on the right arm and that developed 
 within the first two seconds. 
 
 The next day another attempt was made to deter- 
 mine specificity. In the first trial there was a general 
 reaction to all cutaneous stimulation of cheeks, fore- 
 head and both arms. This persisted in the second trial 
 and was accompanied by marked tension of the whole 
 body. In the third trial only the forehead and right 
 arm were stimulated and the reaction was much more 
 marked to the arm stimulation. On the fourth trial all 
 areas were again stimulated but reaction was rather 
 faint except to that of the right arm which this time 
 was very violent. 
 
 A four days interval now elapsed while Partil was 
 away. 
 
 On the next day of experimentation the development 
 of specificity of reaction was again undertaken. On 
 the first trial successive stimulation of the left arm, 
 forehead, right cheek, left cheek, right arm for ten 
 seconds each brought absolutely no reaction. Upon the 
 second trial reaction occurred to all except stimulation 
 of the left arm. Upon a third trial there was no re- 
 action to touching the left arm, forehead and right arm 
 and almost none to the stimulation upon the cheeks. 
 Upon the fourth trial there was reaction only to stimu- 
 lation upon the right arm and this reaction was accom- 
 panied by a smile. This discrimination was not abso- 
 lutely perfected, however, but in the fifth trial reaction 
 
132 CHILD BEHAVIOR 
 
 occurred to the forehead stimulation also, while com- 
 plete discrimination functioned in the sixth trial. This 
 fluctuation is most interesting in connection with the 
 following information. During the four days he was 
 away Partil had been to visit at a place which aroused 
 an old phobia that he had had from the age of two. 
 Since his return he had been nervous and excitable, had 
 not slept well and had refused to sleep in his room 
 alone. 
 
 Two days later he seemed to be in far better condi- 
 tion, although he was not yet sleeping well, and came 
 again to the laboratory. Another attempt was made 
 at determining a specific reaction to the cutaneous stim- 
 ulation. The skin was stimulated upon the left arm, 
 left cheek, forehead, right cheek and right arm. In all 
 seven trials were given that day. In the first trial the 
 child was passive except for a very faint reaction to the 
 stimulation of the left arm and left cheek. In the 
 second trial there was a slight correct reaction to the 
 touch upon the right arm. There was no reaction at 
 all during the third and fourth trials, but in the fifth 
 trial the child reacted to all stimuli, while in the sixth 
 and seventh trials he was again absolutely quiescent. 
 
 The next day, after the first night of real rest which 
 he had had since his trip and when for the first time 
 he had consented to sleep in his own room, specificity 
 was again studied. Upon the first trial all five places 
 of stimulus application were used and all were reacted 
 to with violent twitchings and quiverings of the body 
 but neither here nor in any other trial made that day 
 was Partil's mouth opened once, all reaction being vio- 
 lent body twitchings. In the second trial only the left 
 arm, right cheek and right arm were touched but all 
 gave the reaction. In the third and. fourth, trials the 
 
PRELIMINARY EXPERIMENTS 133 
 
 whole five places were touched and both times the re- 
 action was general. In the fifth trial the bandage alone 
 was sufficient to give marked reaction which increased 
 when the left arm was touched and continued about the 
 same for the stimulation of the right arm. In the 
 sixth trial there was no reaction to bandage or the 
 touch upon the left arm or left cheek but only to the 
 conditioning stimulation of the right arm. In the sev- 
 enth trial this specificity was lacking and response 
 occurred to the bandage itself then to left arm and 
 forehead stimulation as well as to right arm stimula- 
 tion. Work stopped at this point until the next day 
 when four more trials were given but the results were 
 all still non-specific. 
 
 No more attempts were made at developing speci- 
 ficity of the skin stimulus but instead the next day an 
 attempt was made at the development of inhibition or 
 unlearning of the response which had become so gen- 
 eral. The cutaneous stimulation and bandage were 
 applied ten seconds and the child was not fed. This 
 was repeated at the same three minute interval used to 
 develop the reaction. After 6 trials the child was quiet 
 and on the seventh or second quiet trial he was again 
 fed. The next trial showed a very convulsive reaction 
 but this was as much to the bandage as to the bandage 
 plus the cutaneous stimulus. 
 
 The question then arose of developing discrimination 
 between these two. The bandage was at first an indif- 
 ferent factor having been rendered so by habituation 
 to it without feeding but during the series when an 
 attempt was made to develop specificity the stimulus 
 reaction had irradiated so as to include it. This sec- 
 ondary association must next be broken down and we 
 attempted it as follows. The bandage was put on ten 
 
134 CHILD BEHAVIOR 
 
 seconds and no feeding was made. Then after three 
 minutes the bandage was put on 5'', then the cutaneous 
 stimulation was simultaneously presented for 10" more 
 and a feeding was made. After two repetitions of the 
 double procedure the child lay perfectly quiet upon the 
 third trial while in the fourth, fifth and sixth trials he 
 reacted with increasing volume to the correct conditions 
 only. 
 
 After 24 hours this discrimination was tested again 
 and a rather doubtful reaction occurred to the bandage 
 alone the first, second and third times but this was 
 entirely lacking the fourth and fifth times, reaction 
 occurring only in response to cutaneous stimulation. 
 
 Thirty-three days later Partil was again available 
 and the persistence of the touch-open-mouth association 
 tried again. The first trial there was no reaction, the 
 second time there was a vague undifferentiating reac- 
 tion to the bandage but this increased when the cutane- 
 ous stimulation was given. The reaction was still gen- 
 eral on the third and fourth trials but occurred only in 
 response to the cutaneous stimulation in the fourth and 
 fifth trials. 
 
 One more series was attempted with Partil, that of 
 the development of a memory conditioned reflex. An 
 auditory stimulus, the ringing of a metronome, was used 
 for ten seconds and then ten seconds after the ringing 
 stopped the child was fed. As early as the second trial 
 the reaction occurred, but it occurred during the ring- 
 ing of the metronome. Gradually it came later and 
 later after the initiation of the auditory stimulus and 
 finally after 15 trials was delayed until the metronome 
 has stopped. 
 
 The results of the work upon these eight children left 
 no doubt in the mind of the experimenter as to the 
 
PRELIMINARY EXPERIMENTS 135 
 
 feasibility of applying the method of conditioned re- 
 flexes in the study of young children. These children 
 had been approached with the determination that their 
 behavior itself should be made the controlling factor 
 and should be allowed to lead to suggestions for modifi- 
 cation of 'technique and method. The necessity of mak- 
 ing the bodily position to be assumed during the study 
 indifferent had been recognized and with active children 
 who could not be kept lying down the whole time re- 
 course was had to a game of lying them back on the 
 couch (upon which they stayed even when sitting up) 
 at irregular intervals both before the experiments began 
 and in the intervals of the experiment. The bandage, 
 too, could probably have been rendered indifferent in 
 the same way but the fact, entirely unanticipated, that 
 it proved such an important factor in the child's re- 
 actions suggested that the Russian insistence upon 
 simplification could be carried still further in this in- 
 stance and at the same time make it easier for any one 
 person to handle the various factors of child, bandage, 
 stimulation, feeding, apparatus and time control, while 
 it also simplified the number of possible reactions. 
 These could again be simplified by taking off the band- 
 age at once after the feeding as it would eliminate the 
 development of the child's successful attempts to re- 
 move bandage after feeding. This was done with Partil 
 and in all later experiments. 
 
 The trial with Partil of stopping the day's work 
 when the desired reaction was once obtained, or before 
 if fatigue showed, proved far more commendable from 
 the standpoint of evaluation of results as over-learning 
 was decreased to the minimum necessary due to trials 
 for memorial re-functioning. 
 
 That there are great individual and probably also 
 
136 CHILD BEHAVIOR 
 
 developmental differences seems evident, while there is 
 no doubt left in the mind of the experimenter but that 
 innumerable variations of the method may be applied 
 to the solution of almost any problem of child behavior. 
 
 The development of the specificity of reaction in Par- 
 til, its fluctuation under differences in number and 
 order of points of stimulation and in indicating neural 
 disturbances which could not be outwardly detected and 
 were not understood until the report of his mental dis- 
 turbance was afterwards obtained, the evident fluctua- 
 tions due to fatigue of a rather neuropathic organism, 
 all indicate the exquisite sensibility of the behavior re- 
 action here studied. The transient irradiation of in- 
 hibition from a new non-conditioning point of stimula- 
 tion to the old formerly-functioning conditioned reflex 
 is in itself a problem of high speculative interest. 
 
 Although the results are only indicative, they are 
 positively indicative of the possibility of studying in a 
 normal fashion hitherto untouched provinces of child 
 development and a quantitative investigation seemed 
 next in order. 
 
CHAPTER VII 
 
 A QUANTITATIVE STUDY OF THE 
 CONDITIONED REFLEX 
 
 THE group of fifty children, which was practically 
 all of those under seven years of age living in the 
 village and which included in three instances seven-year- 
 old-sisters of younger children, is in some senses a 
 selected, in others an unselected group. The village is 
 healthfully located and simply because it is surburban 
 lacks congestion and slums. The children are probably 
 benefited by these better conditions. Malnutrition is 
 not a problem in the schools and is recognized in the 
 homes in the several cases I found, being seemingly a 
 condition due to other causes than lack of proper feed- 
 ing. 
 
 The home conditions of the children do vary and 
 although the variation may not be as extreme as that 
 which would be found in a large city yet visiting the 
 homes gave data which was most enlightening. On one 
 extreme I met the college woman, studying her children 
 conscientiously and individually, willing and able to 
 give me definite characterizations of each one, knowing 
 his weak as well as strong points, interested, too, in all 
 children, trying to establish a kindergarten for the vil- 
 lage in the hope that it would lead to more genuine 
 consideration of the pre-school child. Then there was 
 the less well-trained but intelligent mother, using com- 
 mon sense in letting her children get daily lessons from 
 
 137 
 
138 CHILD BEHAVIOR 
 
 life through helping care for each other, encouraging 
 Marie to dry the dishes even if one were broken, prais- 
 ing Jackie when he carried away the grass as father 
 raked the lawn, too busy with three or four under school 
 age to be theoretical but yet appealing to me in more 
 than one instance for advice as to whether James should 
 start school this fall or wait until he's fully six and 
 nearly seven, making cogent observations regarding 
 school hygiene, play and teachers. On the other ex- 
 treme were those homes which seemed markedly dis- 
 tinguished by one peculiarity. Although the houses had 
 at least the conventional three rooms on the first floor 
 they were not in use as in the other homes. The front 
 doors were closed, the front porches bare and entrance 
 was made through the back door. The family, in other 
 words, huddled. It ate, dressed, sewed, played, visited, 
 in the kitchen. The members were living under slum 
 conditions when they were absolutely unnecessary and 
 even in the warm weather were seldom found outdoors 
 if we except the playing children who were chased out 
 to be out of the way. From the standpoint then of 
 home and social environment the children were not se- 
 lected. 
 
 As regards their inheritance, variation is again 
 found. Careful observation, carefully verified, showed 
 the following conditions. The parents of most of the 
 children were both living and both normal, the mother 
 running an average American middle-class home, the 
 father working steadily, interested in his family and his 
 home. In one instance the father was paralyzed, had 
 been so for several years, due to a clot in the motor 
 area of the brain. This had been detected by X-rays 
 and was due to a sudden hemorrhage from over-exer- 
 tion. He had always been rather delicate. In another 
 
STUDY OF CONDITIONED REFLEX 139 
 
 instance the mother had a goitre. In another the 
 mother had insane spells resembling psychic epilepsy. 
 In these spells she would strike and beat her five-year- 
 old son without any seeming cause, then suddenly pet 
 and nurse him to make up for it. This occurred six 
 or eight times a day. The woman was seemingly intelli- 
 gent, conversed well and is of people who are in better 
 circumstances than she. The husband and father is a 
 feeble-minded man with a mentality of about ten. He 
 works steadily but cannot even be allowed to drive a 
 team for his employer as he ruins the horses through 
 unintentional misuse. His wages are doled out by his 
 employer as needed else the wife would spend them all 
 for whatever took her fancy and leave the bills unpaid. 
 In another case the mother was rather neurotic, suffer- 
 ing from intense nervous headaches. In one other case 
 the mother was that easy-going type that can manage 
 to keep a family alive and fed due to delicatessen and 
 bakery shops, but would, we feel, make a failure of any- 
 thing where efficiency was demanded. Whether she 
 would be classed as a social inefficient is a doubtful 
 question. In one other case the mother was very large 
 and obese. This condition was accompanied by a coars- 
 ened skin condition, a deep mannish voice and facial 
 hair. The two children who have reached adolescence 
 have at that period developed a similar great stature 
 and obesity. The condition does not resemble a pure 
 acromegaly but one would suspect a definite thyroid 
 abnormality with its concomitant disturbance of other 
 functions. The older children are above average in 
 their school accomplishments. One other abnormality 
 was noticed. This is probably the sort of thing that 
 would never be detected in a survey by one not on 
 intimate terms with some members of the community. 
 
140 CHILD BEHAVIOR 
 
 It is the thing that the village gossips did not talk 
 about and this seemed surprising at first, but rather 
 gives corroborative evidence of the fact that the condi- 
 tion not only exists but exists to the extent found by 
 the investigator, escaping comment just because of its 
 prevalence. Among the fifty children tested the history 
 was obtained that 4 of them were the children born of 
 "forced" marriages, while the mother of another one is 
 reported as having been exceedingly immoral since m^ar- 
 riage. The fact that in all but one of these instances 
 discrepancies of the same sort are reported in other 
 branches of the famil}^ living in other villages indicates 
 the truth of the findings. Whether the condition is 
 unusual or just due to a more intimate knowledge of 
 the situation than is usually acquired cannot be de- 
 termined here. 
 
 Turning now to consideration of the children them- 
 selves let us study them quantitatively. 
 
 The following mathematical evaluations of the meas- 
 urements of the children studied have been made and 
 the correlations of the most important of them calcu- 
 lated: 
 
 1. Chronological age, or the age of the child at the 
 time of the experimentation, expressed in months to 
 the last whole month, including any month completed 
 on either of the two successive days upon which the 
 child was studied. 
 
 2. The first process of the modified Krasnogorski 
 experiments, or the learning ability of the child as 
 expressed in the number of trials necessary to form a 
 sensory-motor association. The assumption being that 
 the fewer the number of trials necessary, the greater 
 the learning ability. 
 
 3. The second process of the Krasnogorski experi- 
 
STUDY OF CONDITIONED REFLEX 141 
 
 ments, or the memorial functioning of the association 
 learned after an interval of twenty-four hours, meas- 
 ured by the number of trials necessary to obtain its 
 refunctioning, fewer trials meaning better memory. 
 
 4. The learning value of the retention, or the sav- 
 ing in number of trials necessary the second day as 
 compared with the number necessary the first day. 
 
 5. The percentage of saving in number of trials 
 saved from first to second day. 
 
 6. The third process of the Krasnogorski experi- 
 ments, or the number of trials necessary to effect un- 
 learning of the associative act learned when condition- 
 ing stimulus is absent. Here again the actual number 
 of trials necessary should theoretically be fewer the 
 greater the intelligence of the child. 
 
 7. As the number of trials needed to develop the 
 unlearning may bear some relation to the number of 
 trials necessary to learn the original association, the 
 relation of these was calculated in the per cent of trials 
 necessary for the learning that was used in bringing 
 about the unlearning. Whether a low percentage indi- 
 cates higher intelligence or not remains to be seen. If 
 the supposition expressed in number six is true, then 
 the same should hold in this case. 
 
 8. The fourth process of the modified Krasnogor- 
 ski experiments, or the number of trials necessary to 
 correct the unlearning developed and to restore the 
 re-functioning of the first association. Here again the 
 number of trials should be less, according to theory, 
 the greater the child's intelligence. 
 
 9. The mental age of the child as expressed by his 
 ability measured upon the Binet scale. These evalua- 
 tions were not made in years but the actual number of 
 points upon which the child succeeded was counted. 
 
U2 CHILD BEHAVIOR 
 
 10. The mental age of the child as expressed by his 
 ability measured upon the Bridges-Yerkes scale. Here 
 again the evaluation was not transposed into years of 
 mental age but left in the total number of points with 
 which the child was credited. 
 
 11. The number of seconds the child required to 
 complete putting all the blocks into the Seguin Form 
 Board, taken upon the first trial upon which the child 
 succeeded without help, three trials being given if 
 necessary. 
 
 12. The number of seconds required to complete 
 the Form Board in the best of the three trials given 
 the first day. 
 
 13. Improvement upon the Form Board upon the 
 first day, being the saving in number of seconds from 
 the first trial to the best of the three given. 
 
 14. The percentage of the original time saved in 
 the best trial made upon the first day. This seems to 
 be a measure of the learning ability of the child. 
 
 15. The improvement in number of seconds saved 
 from the best trial made on the first day to the first 
 trial made upon the second day. 
 
 16. The improvement in number of seconds saved 
 upon the Form Board from the best trial the first day 
 to the best trial the second day. 
 
 17. The percentage of improvement made upon the 
 Form Board from the best trial of the first day to 
 the best trial of the second day. 
 
 18. Success upon the Goddard Adaptation Board 
 as measured by the number of turns successfully com- 
 pleted out of the four possible successes. 
 
 19. The standing height of the child as expressed 
 in millimeters. 
 
 20. The sitting height of the child as expressed in 
 
STUDY OF CONDITIONED REFLEX 143 
 
 millimeters. 
 
 21. The standing-sitting height index, or the stand- 
 ing height in millimeters divided by the sitting height 
 in millimeters. 
 
 22. The weight of the child as expressed in kilo- 
 grams. 
 
 23. The weight-height index, or the weight in kilo- 
 grams divided by the standing height in centimeters. 
 
 24. The dynamometer ability of the right hand, ex- 
 pressed in kilograms. 
 
 25. The dynamometer ability of the left hand, ex- 
 pressed in kilograms. 
 
 26. The average dynamometer ability, expressed 
 in kilograms. 
 
 27. The grip-ability — height index, being the aver- 
 age dynamometer ability in kilograms divided by the 
 height in centimeters. 
 
 28. The grip-ability — weight index, being the aver- 
 age dynamometer ability in kilograms divided by the 
 weight in kilograms. 
 
 29. The spirometer ability of the child as expressed 
 in liters. 
 
 30. The spirometer-ability — height index, being the 
 spirometer ability in liters divided by the height in 
 centimeters. 
 
 31. The so-called vital index or the spirometer 
 ability in liters divided by the weight in kilograms. 
 
 Any further or more detailed discussion of the sig- 
 nificance of these various measurements will be left 
 until we consider the significance of their relations to 
 each other. 
 
 The interpretation of these correlations is, however, 
 not so simple as it may seem at first. In social sta- 
 tistics we are usually concerned with trying to find how 
 
144 CHILD BEHAVIOR 
 
 far two elements, two conditions, are correlated and 
 the mathematical expression which gives us this in- 
 formation is in itself understandable. In this study, 
 also, we wish to know in how far these various measure- 
 ments are correlated but that is only half of our task. 
 In order to evaluate the correlations that we may find 
 it is necessary to know in how far the arrays should 
 be correlated, provided they were the expressions ob- 
 tained by the use of methods of mental examination 
 which were infallibly correct in their diagnosis of nor- 
 mality, defect, and genius. 
 
 If we had any such measure, indicating the various 
 diiferences in mentality as correctly as the stadiometer 
 indicates indifferences in height, the distribution of any 
 unselected group measured by it would probably take 
 the same characteristic form as the distribution of 
 other anthropometric characteristics, that is, it would 
 be a Gaussian distribution. There would be this dif- 
 ference, however. In-so-far as it is harder for any one 
 to reach and surpass the ability expected of him than 
 it is for him to remain intellectually dormant and fall 
 farther and farther behind the constantly increasing 
 norm, we might expect the distribution to be somewhat 
 skewed towards the side of mental superiority. 
 
 This curve skewed towards the upper end is the typ- 
 ical curve that has been found in many studies of esti- 
 mated intelligence through the use of marks, intelli- 
 gence tests, etc. This distribution may be due to a 
 lesser range of variation among those above normal or 
 it may be due to our own mediocrity and consequent 
 inability to properly discriminate and evaluate those 
 factors which really indicate superiority. Whichever 
 the cause this study does not claim to differ from any 
 
STUDY OF CONDITIONED REFLEX 145 
 
 of the rest and will consequently make use of the skewed 
 form. 
 
 Goddard (59) found such a distribution in his study 
 of over fifteen hundred school children tested by the 
 Binet-Simon scale. Indeed, he uses the fact that the 
 distribution is such as a proof that the scale is an 
 accurate one. Whether this is so or not, nevertheless, 
 it is true that the distribution is such a one as we 
 would expect to find with a scale well-nigh perfect. 
 This may be due to the fact that any imperfections in 
 the scale are not general but pertain to perhaps more, 
 perhaps fewer, of the individual tests. In the general 
 findings these errors compensate for each other and 
 give fairly accurate results although the individual find- 
 ings may be more or less unfair. Moreover, any errors 
 due to the functioning of the personal equation of an 
 examiner are here probably balanced by the like errors 
 of other examiners in the opposite direction, and so we 
 have used the data presented by him in the table on 
 page 234 to calculate the correlation coefl5cient of 
 mental and chronological age when its expression takes 
 the form of a Gaussian distribution. The value of this 
 coefficient proved to be + 0.808. Using this coefficient 
 for the sake of rough comparison we shall be able to 
 tell more exactly than by the use of the actual corre- 
 lations alone the significance of the various relations 
 found. 
 
 The following coefficients of correlation have been 
 calculated by the product method. 
 
 What is the significance of these findings .f* A sepa- 
 rate discussion of each one is not necessary but those 
 which seem the most important deserve further analysis. 
 
 According to chronological age the distribution of 
 the fifty children tested is as follows: 
 
II 
 
 d 
 + 
 
 00 
 
 d 
 t 
 
 d 
 1 
 
 00 
 
 ^ 
 
 d 
 1 
 
 CO 
 
 d 
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 2 
 
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 1 
 
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 IN 
 
 d 
 4- 
 
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 d 
 4- 
 
 III 
 
 d 
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 C3S 
 
 d 
 
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 ll 
 5- 
 
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 IN 
 
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 4- 
 
 
 
 
 00 
 d 
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 d 
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 d 
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 d 
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 03 
 
 d 
 + 
 
 d 
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 CO 
 
 d 
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 d 
 
 + 
 
 d 
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 d 
 -t- 
 
 i 
 
 d 
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 d 
 4- 
 
 i 
 
 o 
 1 
 
 00 
 
 ^ 
 
 d 
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 d 
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 d 
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 d 
 1 
 
 
 
 
 
 
 
 d 
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 OO 
 
 d 
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 00 
 
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 00 
 
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 d 
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 J 
 1 
 
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 d 
 + 
 
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 1 
 
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 + 
 
 15 
 
 "5 
 
 d 
 1 
 
 d 
 -l- 
 
 IN 
 
 d 
 1 
 
 d 
 + 
 
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 d 
 1 
 
 00 
 
 d 
 + 
 
 
 
 
 
 
 
 
 n 
 
 05 
 
 d 
 + 
 
 00 
 
 d 
 1 
 
 d 
 1 
 
 OO 
 
 d 
 1 
 
 d 
 + 
 
 (N 
 
 d 
 1 
 
 d 
 + 
 
 
 
 
 
 
 
 
 
 Rede- 
 veloped 
 Learn- 
 ing 
 
 i 
 
 d 
 
 d 
 + 
 
 00 
 
 ^ 
 
 6 
 + 
 
 d 
 1 
 
 05 
 
 rH 
 
 d 
 
 d 
 + 
 
 d 
 1 
 
 
 
 
 
 
 
 
 
 
 % of 
 Leaming 
 for Un- 
 learning 
 
 s 
 
 d 
 1 
 
 d 
 1 
 
 CO 
 
 d 
 1 
 
 f 
 
 OS 
 
 d 
 + 
 
 CO 
 
 d 
 + 
 
 
 
 
 
 
 
 
 
 
 
 4 
 
 o 
 CO 
 d 
 1 
 
 d 
 1 
 
 d 
 1 
 
 d 
 1 
 
 d 
 
 
 
 
 
 
 
 
 
 
 
 
 4k 
 
 d 
 + 
 
 d 
 1 
 
 d 
 + 
 
 d 
 1 
 
 
 
 
 
 
 
 
 
 
 
 
 
 ill 
 
 1 
 d 
 1 
 
 i 
 
 d 
 + 
 
 d 
 1 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 Me- 
 morial 
 Func- 
 tioning 
 
 d 
 1 
 
 o 
 
 S3 
 
 d 
 + 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 il 
 
 d 
 1 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 1 
 1 
 
 a 
 "3 
 
 60 
 
 ^ g 
 'S'3 
 ■no 
 
 O'S 
 
 |i 
 
 3 
 
 il 
 
 SI 
 
 .9- 
 
 il 
 
 1 
 3 
 
 Mm 
 £§0 
 
 O so 
 
 "So 
 
 la 
 
 1 
 
 1 
 
 II 
 
 1 
 
 3 
 
 ft 
 
 
 > 
 
 i 
 
 li 
 
 a 
 35 
 
STUDY OF CONDITIONED REFLEX IV! 
 
 Age in mos. Boys Girls Totals 
 
 12-23 
 
 2 
 
 3 
 
 5 
 
 24-35 
 
 6 
 
 2 
 
 7 
 
 36-47 
 
 S 
 
 3 
 
 6 
 
 48-59 
 
 4 
 
 8 
 
 12 
 
 60-71 
 
 4 
 
 4 
 
 8 
 
 72-83 
 
 6 
 
 3 
 
 9 
 
 84-89 
 
 
 
 3 
 
 3 
 
 Totals 24 26 50 
 
 The predominance of girls is to be regretted but is 
 due simply to the sex ratio in the village studied. 
 
 First, the number of trials necessary for the forma- 
 tion of an association between stimulus and mouth 
 opening for food does not vary sufficiently with the 
 different chronological ages to have a sufficient value 
 for indicating with a high degree of accuracy the 
 differences of learning ability at the different chrono- 
 logical ages, if such differences exist. The correlation 
 coefficient or r of the number of trials with chrono- 
 logical age is only — 0.571 while in our criterion of a 
 sufficiently high value in a Gaussian distribution r is 
 plus or minus about 0.80. 
 
 Let us turn, however, to the original data and inspect 
 it further. We find that the number of trials required 
 by the various children ranges from nine to three. As 
 two correct trials were required before the association 
 was counted as learned, and as one additional trial, the 
 initial one, was needed to introduce the situation and 
 replace a verbal Aufgabe, three is the smallest possible 
 number of trials in which a child could develop the 
 correct functioning of the association. Krasnogorski 
 uses the first correct response as indicating learning, 
 
148 CHILD BEHAVIOR 
 
 however, and so the records of all these cases, accord- 
 ing to his estimation, would lie within the range of two 
 to eight trials. Krasnogorski (100) reports that two 
 to ten trials are sufficient. The difference in the upper 
 limit of the range may be due to the fact that he used 
 younger children than those twelve months old who were 
 the youngest used by the experimenter in the present 
 study, or to time differences, or may be those varia- 
 tions due to differences in the strength of stimuli, 
 method of presentation, or, as is quite likely, to the 
 differences between children being handled by a man 
 and by a woman. 
 
 If we analyze the data for the number of trials re- 
 quired by the children of different chronological ages, 
 using whole years because of the small number of cases, 
 the following results are obtained : 
 
 No. of Cases Age No. of Trials (Av.) Range Mean Var. 
 
 5 
 
 12-23 
 
 8.0 
 
 7-9 
 
 0.8 
 
 7 
 
 24-35 
 
 6.71 
 
 6-8 
 
 0.82 
 
 6 
 
 36-47 
 
 5.33 
 
 3-8 
 
 1.44 
 
 12 
 
 48-59 
 
 3.83 
 
 3-5 
 
 0.83 
 
 8 
 
 60-71 
 
 4.12 
 
 3-5 
 
 0.44 
 
 9 
 
 72-83 
 
 5.0 
 
 3-7 
 
 1.11 
 
 3 
 
 84-89 
 
 4.3 
 
 4-5 
 
 0.44 
 
 These results may be seen expressed in curves on 
 Chart I. 
 
 It is clearly to be seen that up until the age of five 
 the number of trials necessary for the formation of the 
 conditioned association decreases rather regularly as 
 the chronological age of the child increases. Above 
 this the curve is not only less regular but the range 
 of trials necessary for any one age is also greater than 
 
STUDY OF CONDITIONED REFLEX 149 
 
 for the ages just preceding. This can hardly be due 
 to any great difference in the ability of the older chil- 
 dren as a group, for they were in most instances (in 15 
 out of 20) the older brothers and sisters of the younger 
 children used. It may be possible that we have here 
 a symptom of an innate difference of different periods 
 of development. The older child may see or imagine, 
 
 CHART I. RELATION OF LEARKING TO CHROKOLOGI CAL AGS. 
 
 E8 
 
 S4 
 
 o 
 
 lb 
 
 h 
 ;33 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 * 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 ,♦ 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 s 
 
 V 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 s 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 ^ 
 
 
 
 
 
 
 
 
 
 
 > 
 
 H' 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 »^ 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 N 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 S 
 
 
 
 
 
 
 
 
 
 
 ^•>LI_L 
 
 ^ 
 
 
 
 
 
 
 
 
 
 
 
 
 K 
 
 \ 
 
 
 
 
 
 
 
 
 irfl 
 
 ^ 
 
 •^ 
 
 
 1:^ 
 
 ■■^- 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 s 
 
 s, 
 
 
 
 -9^ 
 
 p 
 
 kf 
 
 ^^ 
 
 
 
 
 
 ' 
 
 
 
 
 
 
 
 
 
 
 
 
 
 " 
 
 
 •• 
 
 •T 
 
 ^o 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 •••. 6 mo0. groups 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 __ 
 
 
 KI 
 
 
 
 
 
 
 ^ 
 
 «» 
 
 
 L, 
 
 m^ 
 
 
 
 uEsLa 
 
 BK 
 
 ChroTtological age expressed in months. 
 
 because of his greater experience, and consequent great- 
 er potentiality of associations, possibilities of varia- 
 tion in the procedure to which the younger child is 
 oblivious, being absolutel}^ sure after he has been fed 
 candy under a given condition once or twice that it will 
 appear again under like conditions. Genetically viewed, 
 this difference may be as significant as a mark of old 
 stages of development as are the differences recognized 
 to-day between the adolescent and the pre-adolescent. 
 Calculating the correlation coefficient for the num- 
 
150 CHILD BEHAVIOR 
 
 ber of trials necessary for the formation of the asso- 
 ciation with chronological age for the children under 
 60 months of age we obtain r. equals — 0.816. As the 
 one is a decreasing array and the other an increasing 
 one, the relation is a positive one and comparison with 
 the coefficient of the high value Gaussian distribution 
 assumed as a tentative norm, 0.808, indicates that it 
 has undoubted value as a basis for distribution.* 
 
 It may be interesting to note that no child over two 
 years of age needed more than eight trials while none 
 under that age used less than seven, none under three 
 years needed less than six, while the minimum number, 
 three, was all that were required by a child in the fourth 
 year. Out of the fifty children, regardless of age, ten 
 needed only three trials, eleven needed four trials, eleven 
 used five trials while only seven needed six, five needed 
 seven, four needed eight and two, nine trials. 
 
 If we analyze this data still further and consider the 
 sexes separately we see that there is in sex yet another 
 factor determining differences in the rate of learning. 
 This shows in the table following although some of the 
 differences are obscured by the age grouping. 
 
 No. of Cases 
 
 Age in 
 Months 
 
 Av. No. of Trials 
 for Learning 
 
 Range 
 
 Mean 
 Var. 
 
 Boys 2 
 Girls 3 
 
 12-23 
 
 
 ' 7.0 
 
 8.7 
 
 7 
 8-9 
 
 0.00 
 0.43 
 
 Boys 5 
 
 Girls 2 ■ 
 
 24-35 
 
 
 ■ 6.4 
 
 7.5 
 
 6-8 
 
 7-8 
 
 0.64 
 0.50 
 
 Boys 3 
 
 Girls 3 
 
 36-47 
 
 - 
 
 ■ 6.S3 
 4.33 
 
 4-8 
 3-5 
 
 1.59 
 0.89 
 
 * Some such criterion of the correct value of r must be assumed 
 when diagnostic norms are being studied. An r too near±l means 
 that the factors under observation correlate too highly for the one 
 to be used in selecting variants from a group which will not vary 
 
STUDY OF CONDITIONED REFLEX 151 
 
 No. of Cases 
 
 Age in 
 Months 
 
 Av. No. of Trials 
 for Learning 
 
 Range 
 
 Mean 
 Var. 
 
 Boys 4 ^ 
 Girls 8 
 
 48-59 
 
 1 4.50 
 3.50 
 
 3-5 
 3-5 
 
 0.75 
 0.62 
 
 Boys 4 1 
 Girls 4 
 
 60-71 
 
 4.50 
 3.75 
 
 4-5 
 3-4 
 
 0.50 
 0.38 
 
 Boys 6 
 Girls 3 ^ 
 
 7S-83 
 
 4.67 
 5.67 
 
 3-6 
 
 4-7 
 
 1.11 
 1.11 
 
 Boys 
 
 Girls 3 ^ 
 
 84-89 
 
 
 4.33 
 
 4-5 
 
 0.44 
 
 Expressed as a curve for the purpose of easier com- 
 parison, this table gives the distribution seen on Chart 
 II. 
 
 Pursuing the analysis we find that almost without 
 exception the average age of the boys decreases as the 
 number of trials necessary for learning increases. With 
 the girls, however, the age-learning relation is much 
 less definite. The mode for learning with the boys is 
 at five trials while for the girls it is at four, although 
 the number there is almost equaled by the number learn- 
 ing in three trials. This may be seen in the following 
 table : 
 
 Relation of Learning to Sex and Age 
 
 No. of trials needed 
 for learning 3 4 5 6 7 8 9 Total 
 
 No. of boys 3 3 7 6 3 2 ..24 
 
 Average age.... 69 62.7 62.3 44.5 20.6 34.5 
 
 No. of girls 7 8 4 1 2 2 2 26 
 
 Average age.... 52.6 69.1 53.8 77.0 52.5 21.5 18.0 
 
 in the other factor also. For instance, a mental test which has an 
 r of it 0.95, or so, with chronological age is apt to indicate an 
 ability so dependent upon chronological age that it varies with 
 chronological age independent of actual mental ability. 
 
152 
 
 CHILD BEHAVIOR 
 
 The correlation between chronological age and the 
 number of trials needed for memorial functioning of 
 the association after 24 hours is — 0.065, which shows 
 such a slight decrease as the age increases as to appear 
 negligible. Again recourse to our actual figures may 
 be helpful. Since two trials were required before the 
 association was counted as functioning that is the 
 smallest number that could be used. Thirty-six of the 
 fifty children gave a positive reaction on the first and 
 
 CKARTII. RELATION 0? LSARKIHG TO CHROK, AGE AOT) SEX. 
 
 iJ, 9 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 ^ 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 E fl 
 
 
 
 *• 
 
 ,, 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 (4 
 
 
 
 
 
 •• 
 
 ,^ 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 ^7 
 
 
 
 
 
 
 
 ', 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 (4 
 
 
 r*^ 
 
 
 
 ' 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 -26 
 
 
 
 
 
 
 ^ 
 
 «. 
 
 
 
 
 ^ 
 
 
 
 
 
 
 
 
 
 
 
 ■ 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 ', 
 
 
 
 s> 
 
 
 
 
 
 
 
 
 
 
 
 , 
 
 
 
 
 25 
 
 
 
 
 
 
 
 
 
 
 
 
 
 S 
 
 
 
 
 
 
 
 
 
 
 ' 
 
 • 
 
 
 
 ;3 
 
 
 
 
 
 
 
 
 
 
 * 
 
 
 
 
 s. 
 
 
 
 
 
 « 
 
 ^ 
 
 
 sua 
 
 
 
 ^» 
 
 
 ?f4 
 
 
 
 
 
 
 
 
 
 
 
 
 •» 
 
 
 
 
 
 
 
 
 
 
 
 
 
 « 
 
 ^ 
 
 
 
 
 
 
 
 
 
 
 
 
 
 •• 
 
 ,, 
 
 
 
 , 
 
 . 
 
 * 
 
 
 
 
 
 
 
 ,<» 3 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 <i 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 h 2 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 o I 
 
 Ill, "boys 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 -r,,- girls 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 ^0 
 
 
 
 
 sm 
 
 ^ 
 
 
 ,^ 
 
 mm 
 
 
 
 
 
 »i 
 
 ■n 
 
 
 >T3>I 
 
 
 
 m 
 
 m 
 
 Chronological age expressed in months. 
 
 second trials, 9 on the second and third trials, while 
 one took 4 trials, two required five, one needed six and 
 one seven trials. Evidently in most of them the asso- 
 ciation was so firmly developed that a twenty-four hour 
 interval had not reduced it sufficiently to bring it below 
 the functioning limen. Nor is the distribution of those 
 who needed more than two or three trials greatly in- 
 fluenced by age. The one who required seven trials 
 was IS months old but the one who required 6 trials 
 
STUDY OF CONDITIONED REFLEX 153 
 
 was 77 months old and the distribution of the rest was 
 very irregular. 
 
 The correlation of the number of trials needed in 
 learning with the number needed after the ^i-hour 
 interval is + 0.22, or a shght indication that those 
 who needed more trials for learning were not, as is 
 usually supposed, more retentive but required likewise 
 a greater number of trials to re-establish the associa- 
 tion. Some interesting relations of the learning and 
 memorial function are seen in the following table: 
 
 Relation of Memory to Learning 
 
 No of Trials Range of Trials Av. No. of Trials Mean 
 
 for Learning No. of Cases for Remembering for Remembering Deviation 
 
 fBoys 3 2 2.00 .00 
 
 3 \ Girls 7 2 2.00 .00 
 [ Both 10 2 2.00 .00 
 rSoys 3 2 2.00 .00 
 
 4 \ Girls 8 2-5 2.50 .75 
 [Both 11 2-5 2.36 .59 
 [Boys 7 2-6 3.29 1.04 
 
 5 \ Girls 4 2 2.00 .00 
 [ Both 11 2-6 2.82 .89 
 fBoys 6 2-3 2.33 .43 
 
 6 \ Girls 1 2 2.00 .00 
 [Both 7 2-3 2.29 .41 
 fBoys 3 2-7 3.70 2.23 
 
 7 \ Girls 2 3-5 4.00 1.00 
 [Both 5 2-7 3.80 1.76 
 fBoys 2 2-3 2.50 .50 
 
 8 I Girls 2 2-3 2.50 .50 
 
 [Both 4 2-3 2.50 
 
 .50 
 
 9 Girls 2 2 2.00 .00 
 
154 CHILD BEHAVIOR 
 
 These results do not confirm the rather generally 
 accepted thesis that the greater the number of trials 
 necessary for learning, the more efficient the reproduc- 
 tion, as both the most facile and the slowest learners 
 are more efficient than those intermediate in type. 
 
 Let us turn now to the third Krasnogorski process, 
 or the unlearning of the previously developed associa- 
 tion. It was found impossible to effect this unlearning 
 without severe emotional disturbances in the youngest 
 nine of the children tested. The palliative effect of the 
 candy in the learning experiment was more vividly 
 understood when this attempt was made to use the 
 bandage and not feed. Usually the second, always the 
 third or fourth trial, brought crying and no further 
 attempt was then made, chiefly because of the unfavor- 
 able effect of the crying upon the other children play- 
 ing near, and the effect of reported crying upon the 
 mothers of the community. No difficulty was experi- 
 enced with children over twenty-eight months of age. 
 The group in whom unlearning was developed conse- 
 quently includes only 41 children ranging in age from 
 29 to 89 months. 
 
 The average rate of unlearning for children of the 
 different ages and sexes may be seen in the table on 
 page 155. 
 
 From this we can see that there is in general a de- 
 crease in the number of trials needed for unlearning 
 as the chronological age increases. The average num- 
 ber of trials needed by boys and girls of the same 
 chronological age likewise differs considerably and there 
 is an accompanying difference in the range of number 
 of trials and in variability in the two sexes. 
 
 The correlation between the number of trials neces- 
 sary to effect the unlearning and chronological age is 
 
STUDY OF CONDITIONED REFLEX 155 
 
 No. of Cases 
 Boys 4 
 Girls 5 
 
 Boys 3 
 Girls 
 
 Boys 
 
 Girls 
 
 Boys 
 
 Girls 
 
 Boys 
 
 Girls 
 
 Boys 
 
 Girls 
 
 Boys 
 
 Girls 
 
 Av. No. of Trials 
 Age in Months for Unlearning 
 
 12-29 
 
 MeanVar. 
 
 30-35 
 
 36-47 
 
 48-59 
 
 60-71 
 
 72-83 
 
 84-89 
 
 f Failure 
 Failure 
 
 
 
 
 
 6.33 
 
 5-8 
 
 1.11 
 
 '8.33 
 
 5-12 
 
 2.44 
 
 9.67 
 
 9-10 
 
 0.44 
 
 7.00 
 
 3-9 
 
 2.00 
 
 8.38 
 
 5-11 
 
 1.63 
 
 6.50 
 
 5-9 
 
 1.50 
 
 9.50 
 
 7-12 
 
 2.00 
 
 6.33 
 
 4-10 
 
 1.78 
 
 5.33 
 
 4-7 
 
 1.11 
 
 5.33 
 
 5-6 
 
 0.44 
 
 — 0.316, which corroborates the fact shown by the 
 table above that there is only a slight decrease in the 
 number of trials needed as age increases. The num- 
 ber of trials necessary to unlearn the association varies 
 more than the number required in the learning of it. 
 The distribution frequency is as follows: 
 
 %h J 3 4 5 6 7 8 9 10 11 12 Failures 
 
 required. ) 
 
 No. of 
 cases 
 
 ;*} 1 2 10 4 4 6 5 5 2 
 
 This table indicates a double distribution in the rate 
 of developing unlearning, the one with a mode of 5 
 trials, in some instances approaching in ability the 
 
156 CHILD BEHAVIOR 
 
 minimal limit of the task, the other type more variable 
 among themselves with a mode less well expressed but 
 lying probably at 8, 9 or 10 trials. 
 
 The extremes of number of trials necessary to effect 
 unlearning are those mentioned by Krasnogorski for 
 although he makes the general statement that it de- 
 velops in 5 to 10 trials in normal children he also says 
 in one instance that the association broke down after 
 three trials in one six-year-old while in another in- 
 stance it took eleven trials without stimulation before 
 on the twelfth the reaction was lacking. But as there 
 may have been great differences in method, length of 
 stimulation times and intervals in the work he reports 
 and that reported here this coincidence may not be 
 assumed to mean corroboration of the accuracy of the 
 findings in either of our series. If he used only one 
 trial without positive response as an indication of the 
 degeneracy or decreased functional efficiency of the 
 conditioned reflex then by comparison we again, as in 
 the learning process, find the mechanism more easily 
 developed in our series. 
 
 If we analyze the results on unlearning in their re- 
 lation to the number of trials needed in the original 
 learning we find r equals — 0.450, while in the relation 
 between unlearning as measured in per cent of the 
 learning trials it required and learning itself r equals 
 — 0.774. Tabularly distributed this relation may be 
 seen on page 157. 
 
 In general the greater the number of trials that was 
 necessary to develop the conditioned reflex the less the 
 number required to break it down. 
 
 If we analyze these results stiU further, according to 
 sex, we find the distribution for either sex is quite dif- 
 ferent from that of the other. 
 
STUDY OF CONDITIONED REFLEX 157 
 
 Relation of Learning to Uni^earning 
 
 No. of No. of Trials needed to 
 
 Cases effect Unlearning No. of Trials used in Learning Av. No 
 
 3 4 5 6 7 8 
 
 13 1 5 
 
 2 4 1 1 6.5 
 
 10 5 2 4 3 1 5.4 
 
 4 6 1111 4.5 
 
 4 7 3 1 4.25 
 6 8 2 3 1 4.3 
 
 5 9 3 11 3.6 
 5 10 2 3 4.2 
 2 11 11 3.5 
 2 12 1 1 5.0 
 
 Average No. 9.2 7.4 5 5 8 6.5 
 
 Sex and Age Distribution with Number of Trials 
 FOR Unlearning 
 
 No.oftridiforUnUaming 8 4 5 6 7 8 9 10 11 12 F.* 
 
 No»ofBoy9 116 2233 10 14 
 
 No. of Girls 14 22324 2 15 
 
 Av.No.of trials on Learning 
 
 Boys 5 6 5.8 6.5 4.5 5 4 3 ... 7 6.5 
 
 GirU 7 4.8 8.5 4 3.7 4.55 4.5 8.5 3 8 
 
 Average age. Boys 52 73 58.8 56.5 59 50.3 67 74 ... 36 20 
 
 Girls 80 75.8 71.5 70.5 59 45 44.6 66.5 70 20.8 
 
 * F » Failures. 
 
 The range of distribution of the boys is wider, ac- 
 cording to the number of trials used, than is that of the 
 girls although the opposite was true of the learning 
 process. The most frequent form of development of 
 the unlearning took five trials with the boys while with 
 the girls the development in five trials and development 
 in ten trials occurred with equal frequency. With the 
 boys the learning rate for those who needed five trials 
 or less for unlearning was slower than it was for any 
 
158 
 
 CHILD BEHAVIOR 
 
 of those who needed more trials if we make an excep- 
 tion of one case who took twelve trials to unlearn and 
 had needed seven to learn. With the girls the number 
 of trials for learning is highest for those needing four 
 or five trials to effect the unlearning and then gradu- 
 ally decreases as the difficulty of unlearning increases 
 but with another rise in learning difficulty for those 
 who had taken ten trials to unlearn the association. 
 
 CHAM llla. RELATION 07 lEARUlNO AND UNLEAWIINC TO CHROH. AGE AND 3BX (BOYS). 
 
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 CJ ■# tfl eo o I 
 
 10N'<i'0<COM'3'«)«)0<V-«*<OcOON'4"'PCOO(S}'t<oa)ON«1"i 
 
 Chronological age expressed in.monthe. 
 
 With the boys we have an almost homogeneous group, 
 finding less difficulty in developing unlearning the more 
 slowly they learned or the less plastic they were to 
 receive the more mobile they were to erase or modify. 
 With the girls we have one group learning slowly and 
 unlearning easily and also a group learning slowly and 
 unlearning with difficulty, while those who learn more 
 readily unlearn with proportionately increasing diffi- 
 culty. Have we here in these early differences an indi- 
 cation of conditions which later lead to the much more 
 
STUDY OF CONDITIONED REFLEX 159 
 
 frequent nerve disturbances among girls? The fact 
 already pointed out by Krasnogorski that neuropathic 
 cases are apt to unlearn conditioned reflexes very slowly 
 seems to re-enforce the probability of any such an 
 inference. 
 
 Although less accurate than a rough polygon would 
 be, Charts III a and III b show more clearly the rela- 
 tions age, sex, learning and unlearning hold to each 
 
 CHART Illb. RELATION OP LEARMIHO AND UNLEARNING TO CHROH. ASE AST> SEX (GIRLS). 
 
 S'12 
 I- 
 
 I? 
 
 V 
 
 o 
 
 h 
 
 a 
 
 <a 3 
 * 
 "S 2 
 
 ol 
 
 io 
 
 ^ 
 
 P 
 
 i; 
 
 U 
 
 £====5 
 
 A 
 
 Learning 
 Unlearning 
 
 CM^lOa)OM'<l'<0 a]OM«<S00OC14<<OCDOCM'<«<<O00O(>)V<0C0O< 
 
 Chronological age expressect in vonths. 
 
 other. Above 6 years, i. e., 72 months of age, our data 
 is too scanty to enable us to analyze what seems to be 
 a very complex matter but below that the diff*erences 
 are more clearly seen. 
 
 Up until the age of two years and a little over the 
 girls learn more slowly than the boys. From the age 
 of about two until six they learn more rapidly than 
 boys of the same age with only one exception. 
 
 Unlearning, on the other hand, is in every case but 
 one harder for the girls than for boys of the same age 
 
160 CHILD BEHAVIOR 
 
 up until six years of age. 
 
 The fourth mechanism studied was that of re-func- 
 tioning of the conditioned reflex which had been un- 
 learned. Krasnogorski uses the term "breaking-down" 
 or "degenerescence" to denote the process which I have 
 called unlearning. Those two terms together with a 
 consideration of this fourth process itself give a better 
 insight into its mechanism. In all of the 41 cases in 
 whom the destructive eff*ect of stimulating without feed- 
 ing was seen the unlearning was neutralized and learn- 
 ing redeveloped with little difficulty. Two successive 
 reactions were necessary to be sure the response was 
 not accidental and in 38 of the children the first two 
 after the renewed feeding were all that were necessary 
 as they reacted positively from the first renewed feed- 
 ing. In two cases three trials were necessary and in 
 one case four. It is interesting to note that the two 
 cases needing three trials were both over six years of 
 age while the one needing four trials was only 51 
 months old, a child rather above usual intelligence, who 
 formed a conditioned reflex in five trials but who needed 
 ten trials to effect unlearning. 
 
 As might be expected from this uniformity of results 
 correlation of redevelopment of learning with other 
 functions is almost lacking, r for chronological age 
 being only + 0.081 and the highest, that with the num- 
 ber of trials needed for memorial functioning of the 
 conditioned reflex, being only -f- 0.228 and conse- 
 quently insignificant. 
 
 The regularity of these results leads to a different 
 view concerning this fourth process. It is not the re- 
 building of an association that has been broken down 
 completely although reaction is completely lacking. 
 Instead the mechanism of unlearning may be looked 
 
STUDY OF CONDITIONED REFLEX 161 
 
 upon as a process which reduces the strength of the 
 association just far enough to take it below the limen 
 of response and consequently only enough new asso- 
 ciations are needed to raise it once more above the 
 threshold. It seems relatively valueless as a method 
 of studying mental processes when used in this form. 
 Undoubtedly a study of the functioning of the re- 
 developed association, comparing it with its primary 
 functioning before modification by unlearning, would 
 throw still more interesting light upon the relation of 
 the learning and unlearning processes. At least the 
 field is one of speculative interest although the results 
 I have obtained throw very little light upon the mental 
 processes of the child in this respect. 
 
 Before making any further analysis of these pro- 
 cesses it will be well to study the group from the stand- 
 point of other tests given. 
 
 RESULTS OBTAINED BY OTHER TESTS 
 
 In evaluating the measurements obtained by the use 
 of the Binet and Bridges- Yerkes scales all calculations 
 have been made upon the total number of points gained. 
 This gives one a chance to study the value of the test 
 series apart from any arbitrarily determined age value 
 which has been assigned. This seemed especially im- 
 portant for the Binet evaluations as most people fail 
 to recognize in them a point scale from which the 
 Yerkes scale differs chiefly in that it has selected a 
 limited number of questions, chiefly from the Binet, and 
 has then made a higher number of points of gradation 
 possible through more minute qualitative classification 
 and a consequent higher evaluation of results than they 
 were given in the Binet. 
 
 The correlation between chronological age and Binet 
 
162 CHILD BEHAVIOR 
 
 grading is + 0.949. This is much higher than the 
 indicated correlation of a Gaussian distribution. 
 Whether this is an error or not is difficult to decide. 
 The tests surely do not pick out in a prognostic man- 
 ner any large number of deviates from the norm. 
 Whether there are, however, significant deviations pres- 
 ent at this early age in a larger proportion of children 
 is still an unanswered question. 
 
 The correlation of the Yerkes evaluations and age 
 is -f- 0.893. This is probably a more highly prog- 
 nostic distribution. The inventor of this scale might 
 justly criticize the usage of it on the younger children 
 since he states (191, p. 89) that the scale is of little 
 value below the age of three years and seven months. 
 As a matter of fact it gives a rather regular distribu- 
 tion, approximating that of the Binet, between the 
 ages of two and four, and above that age it differs 
 little from the Binet in general trend but because of 
 higher evaluation of each test it gives greater indi- 
 vidual variations. This may readily be seen in the 
 following curves which show the relative achievement 
 of each child on the two scales, considered with respect 
 also to chronological age. 
 
 An analysis of the ratings by the Binet or Yerkes 
 tests based upon sex brings out very little that is new. 
 The individual cases of either sex are now higher, now 
 lower, in the number of points they receive credit for 
 although in general children of about the same chrono- 
 logical age seem comparable regardless of this factor. 
 But with such a small number of children, all in the 
 period where a few months' development may mean 
 great differences in the ability to do tests, there is no 
 adequate basis for a study of sex differences. The 
 number of children of both sexes who are of any one 
 
STUDY OF CONDITIONED REFLEX 163 
 
 chronological age is too small and too irregularly 
 divided between the two sexes to make it worth while 
 presenting the comparisons in detail. 
 
 If we analyze out the various cases falling below the 
 general level by either, or rather by both, Binet and 
 Yerkes tests, since in all the grosser instances these 
 
 BIHET Airo POIirr scale RATIHGS to CHHONOLOGICAI. AGS. 
 
 Cases arranged numerically according te chronological age. 
 
 coincide, we find the following to be the children who 
 deviate the most (See Chart IV). 
 
 Case 26, female, is the daughter of the woman de- 
 scribed as immoral since married. The child to a clini- 
 cian appears dull in many ways, needs to be told things 
 again and again and is very babyish. She is undoubt- 
 edly the dullest girl studied. 
 
 Case 38 is the son of the feeble-minded man and the 
 insane woman. 
 
 Case 29 is the daughter of the woman with goitre 
 
164 CHILD BEHAVIOR 
 
 and seems to be rather slow about doing things but 
 does not seem to be really defective. 
 
 Cases 28 and 35 are brothers. They are both called 
 dull when compared with their older sister, case 50, but 
 although below their compeers are not feeble-minded so 
 far as can be determined. They are of normal but 
 rather inferior, slow, easy-going stock. 
 
 The relation of the evaluations by either of these 
 methods to the Krasnogorskian results is not so simple. 
 
 If we study the mental age of the group when dis- 
 tributed according to the number of trials they used 
 for learning the conditioned association, regarding also 
 age and sex, we find evidences that the relation is very 
 complex. On the Binet all the averages for boys except 
 for those taking 8 trials for learning show that the 
 Binet age increases as the chronological age increases 
 for each of the sub-divisions according to the number 
 of trials needed for learning and that in any group of 
 the same age the mental age decreases as the number 
 of trials needed for learning increases. In the two 
 cases taking 8 trials for learning the mental age is 
 slightly greater than for those taking seven trials or less 
 but this variation is probably due to chance working 
 upon such a small number of cases. Also, the younger 
 boys tend towards slower learning. 
 
 Exactly the same condition holds for the mental age 
 of boys calculated by the Yerkes scale except that the 
 differences according to chronological age and rate of 
 learning seem accompanied by greater but less regular 
 variations in mental age. 
 
 The distribution of the girls on both scales seems far 
 less regular. Under any one of the groups formed by 
 division according to the number of trials used on the 
 learning the mental age increases with the chronological 
 
STUDY OF CONDITIONED REFLEX 165 
 
 age, except in the group requiring four trials which 
 includes at the points marked ° the two brightest chil- 
 dren for their ages that were tested, while ° ° indicates 
 case 26, the dullest girl tested. 
 
 The relation, under any one chronological grouping, 
 of mental age and the number of trials required to form 
 the association is not regular although it indicates that 
 in general the number of trials necessary is less with 
 some dull children than with average children while 
 other dull children take longer to learn than the average 
 child. Only children under three years of age take as 
 many as eight or nine trials and here the duller child 
 of an equal age takes longer to learn. 
 
 These relations may be best seen in the tables follow- 
 ing. The correlation between learning and Binet rating 
 is — 0.588 while with evaluations by the Yerkes scale 
 it is — 0.589. In the tables the figures represent the 
 
 Relation of Learning to Binet with Analysis by 
 Sex and Age 
 
 Age in months Number of trials required to develop learning. 
 
 3 4 5 6 7 8 9 
 
 ^^-^^{Es: ' 7 i 
 
 ^^^^{oiris 16 17 15 16 
 
 .o^Q / Boys 24 20.6 
 
 ^^^^\ Girls 19°° 27.5° 22 
 
 60-71 / ^«y« 2^-^ ^^ 
 
 ^"^n Girls 28 27.3 
 
 „a oq / Boys 30.5 29.5 28.5 
 
 '^ "^ \ Girls 34° 28 32 
 
 84-89 Girls 32.5 32 
 
 Av. Age Boys 28.3 22.7 24.1 17.8 8.3 14.0 
 
 by Girls 19.9 29.5 22.0 28.0 19.5 11.5 5.5 
 Binet Both 22.4 27.6 23.4 19.3 12.8 12.8 5.5 
 
166 CHILD BEHAVIOR 
 
 Relation of Learning to Yeekes with Analysis by 
 Sex and Age 
 
 Age in months 
 
 Number of i 
 
 Irials req 
 
 wired to c 
 
 levelop I 
 
 earning. 
 
 
 
 3 
 
 4 
 
 5 
 
 6 
 
 7 
 
 8 
 
 9 
 
 '^Hg^s 
 
 
 
 
 
 
 
 
 
 
 
 ^H^^s 
 
 
 
 
 5.25 
 
 
 
 6 
 8 
 
 
 ^^&s 
 
 10 
 
 11 
 
 10 
 
 
 7 
 
 9 
 
 
 ^^^o{^^l 
 
 29 
 15°° 
 
 27.5° 
 
 16.3 
 12 
 
 
 
 
 
 «o-^ir^?£ 
 
 28 
 
 22 
 24.3 
 
 20.5 
 
 
 
 
 
 72-83 {Bgfl 
 
 30.5 
 
 32° 
 
 27.5 
 
 27.5 
 20 
 
 31 
 
 
 
 84-89 Girls 
 
 
 31.5 
 
 33 
 
 
 
 
 
 Av.Age Boys 
 
 30.0 
 
 18.3 
 
 20.6 
 
 12.7 
 
 2.3 
 
 7.5 
 
 
 by Girls 
 
 16.1 
 
 28.0 
 
 16.2 
 
 20.0 
 
 15.5 
 
 4.0 
 
 
 
 Yerkes Both 
 
 20.3 
 
 25.4 
 
 19.1 
 
 13.7 
 
 7.6 
 
 5.8 
 
 
 
 average rating by BInet or Yerkes tests of the children 
 who by sex, age and number of trials needed for learn- 
 ing belong in a group. The ratings are all expressed 
 in points for which credit was given. 
 
 If we make the same type of distributive analysis 
 upon the basis of the number of trials necessary to 
 develop unlearning we find that for both the boys and 
 the girls the mental age increases as the chronological 
 age within each and every subdivision made according 
 to difficulty of unlearning. This is true on both the 
 Binet and Yerkes distributions but with one exception 
 in both. In the group needing 9 trials for unlearning 
 there is a deviation, the case marked #, which is case 
 38, the son of the feeble-minded man and the insane 
 woman. 
 
 If within any one division according to chronological 
 age we compare the mental ages of those requiring 
 
STUDY OF CONDITIONED REFLEX 167 
 
 different numbers of trials to unlearn we find sex dif- 
 ferences. The mental ages of the boys increase as the 
 number of trials increases up to a certain point, then 
 decrease as unlearning becomes still more difficult. 
 
 Relation of Binet Age to Unlearning, Age and Sex. 
 
 Age in 
 months 
 
 Number of trials required to develop unlearning. 
 3466789 10 
 
 12 
 
 12 to 23 f Boys . . 
 
 \ Girls . . 
 
 24 to 35 / Boys . . 
 
 ....... \ Girls . . 
 
 26 to 47 / Boys . . 
 
 \ Girls . . 
 
 48 to 59 /Boys 17. 
 
 1 Girls . . 
 
 60 to 71 / Boys . . 
 
 \ Girls .. 
 
 72 to 83 / Boys . . 
 
 \ Girls . . 
 
 84 to 89 Girls . . 
 
 12.0 16.0 
 16!0 '.'. 
 
 12.0 
 19 '.0 
 
 Fail- 
 urea. 
 
 5.0 
 5.6 
 11.0 
 11.5 
 
 15.0 
 
 26.0 
 24.0 
 
 19 
 
 28.0 28.5 
 
 S2.0 28.0 
 
 .. 31.0 
 
 22.0 .. 
 
 .. 23.5 
 30.0 .. 
 
 .. 28.0 28.0 
 
 31.0 .. 31.0 
 .. 34.0 .. 
 
 35.1 .. 
 
 16.0 
 23.5 
 23.0 
 19.# 
 
 17.0 
 18!5° 
 
 36:it# 
 
 20.0 
 26^0 
 
 28.0 
 
 Av age 
 Binet 
 
 ' age f Bo 
 by Gi 
 ;iaet I, Bg 
 
 Boys 17.0 
 Girls . . 
 Both 
 
 28.0 22.2 23.5 26.0 
 32.0 29.0 27.0 31.0 
 20.0 24.9 25.2 28.5 
 
 20.7 22.0 30.0 
 25.0 19.5 17.8 
 
 22.8 21.0 20.2 
 
 15.0 8.0 
 
 23.0 27.0 8.2 
 
 21.5 8.1 
 
 Relation of BBiDaEa-YEBKES Age to Unlearning, Age and Sex. 
 
 Age in 
 months 
 
 Number of trials required to develop unlearning. 
 4 5 6 7 8 9 10 11 
 
 12 
 
 Boys 
 
 Girls . . 
 Boys 
 
 Girls . . 
 Boys 
 
 Girls . . 
 
 Boys 10.^ 
 
 Girls . . 
 Boys 
 
 Girls . . 
 
 72 to 83 / Boys . . 
 
 Girls . . 
 
 84 to 89 Girls .. 
 
 12 to 23 
 24 to 35 
 36 to 47 
 48 to 59 
 66to7i 
 
 4.0 
 9!o 
 
 26.0 
 20.5 
 
 26.0 
 31. 
 
 27.5 29 
 20.0 . 
 29.5 37 
 
 Av, age f Boys 10.0 
 
 by ] Girls . . 
 Yerkes I Both 
 
 26.0 18.2 
 31.0 26.2 
 28.6 21.4 
 
 6.0 
 
 ii!o 
 
 20.0 .. 
 
 .. 22.0 
 
 30.0 .. 
 
 29.0 23.0 
 
 .. 33.0 
 
 32.0 .. 
 
 10.0 
 24.0 
 26.0 
 
 14. S 
 
 25.0 16.7 
 30.5 22.3 
 27.8 19.5 
 
 20.7 
 18.0 
 19.6 
 
 16 
 
 5 28 
 17 
 
 Fail- 
 ures, 
 
 0.0 
 0.0 
 4.5 
 4.0 
 
 2.2 
 1.6 
 5 1.9 
 
 This seems to be the situation although a complete dis- 
 tribution at any one age is lacking but the cases of 
 lower mentality are on the ends of the various distribu- 
 tions according to number of trials needed. Case # 
 is the case 38 mentioned above. Case ### is case 
 28 also mentioned before as rather dull, while case 
 ## indicates the child from the family where there 
 
168 CHILD BEHAVIOR 
 
 seems to be some glandular disturbance which brings 
 abnormal obesity from adolescence. This boy as yet 
 shows no physical signs of the abnormal development. 
 Among the girls the duller ones seem intermediate 
 in range while the brighter ones unlearn either more 
 rapidly or more slowly. Case ° is number 26 described 
 above while case °° is the daughter of the woman with 
 goitre. 
 
 In general it seems evident that rating the child by 
 either Binet or Yerkes and at the same time placing 
 him relatively on the Krasnogorski processes brings out 
 complementary evidence, from the two extremely dif- 
 ferent measures, of the child's ability relative to the 
 group. 
 
 Let us consider next the results obtained upon the 
 Seguin Form Board. In all only 89 children were able 
 to complete the task of placing each of the ten blocks 
 where it belonged. Of the eleven who failed nine failed 
 completely and the other two were unable when they 
 had incorrectly covered a hole to go ahead and correct 
 their error. All children were given three trials one 
 right after the other and no more than three. For 
 the 39 who succeeded the following correlation with 
 chronological age were calculated: 
 
 Initial time — 0.774 
 
 Best time first day — 0.806 
 
 Improvement first day + 0.011 
 
 % improvement first day + 0.442 
 
 Improvement from best first day 
 
 to first trial second day — 0.302 
 
 Improvement from best first day 
 
 to best second day — 0.482 
 
 Improvement from best first to 
 
 best second day in % — 0.512 
 
STUDY OF CONDITIONED REFLEX 169 
 
 The initial time on the Form Board is not a valuable 
 nor a reaUy correct value with several of the children 
 as it was necessary to help them in order to enable 
 them to comprehend what was wanted from them. None 
 of the other methods of rating their ability has a suffi- 
 ciently high correlation coefficient to be worth studying 
 intensively except the best Form Board time the first 
 day. This was the rating which was consequently 
 selected for correlation with other findings on the same 
 children as well as for analysis independently. 
 
 The r between Form Board time on the best trial and 
 Binet age is — 0.799, or the time decreases as the men- 
 tal age increases. The correlation with the Yerkes age 
 is very nearly the same, being — 0.798. The correla- 
 tions between Form Board time and the development 
 of learning and unlearning are very low, indeed negligi- 
 ble, being only + 0.228 and + 0.199 respectively. A 
 tabular analysis gives very little more information re- 
 garding the reason for this non-conformity. A curve 
 plotted on the individual cases arranged in order of 
 merit or speed on the Form Board shows that the rate 
 of completing the task decreases as age or as mental 
 age decreases. There is some relation to learning: those 
 who learn most quickly are not, however, the quickest 
 on this task but rather nearer the middle of the group, 
 while the slowest learners are slowest here also. The 
 girls seem somewhat more rapid than the boys. 
 
 The lack of a higher correlation may probably be ex- 
 plained in the following manner. A child who forms 
 a conditioned reflex or conditioned association rapidly 
 Tuay learn just as rapidly on the Form Board hut in his 
 learning if there be any error due to a false move or 
 to trial and error learning in general he learns that 
 false move as a part of the procedure and he then has 
 
170 
 
 CHILD BEHAVIOR 
 
 to unlearn it before it drops out of his behavior. This 
 lengthens his total reaction time and may persist for 
 a number of trials. Such an explanation can not be 
 proven to be correct without micromotion study but ex- 
 perience leads the writer to believe that it may be at 
 least one of the factors at work. 
 
 The accompanying tables give the results obtained 
 from an analysis of the Form Board times in the groups 
 homogeneous as regards age, sex, learning and unlearn- 
 ing ability. The figures in the tables indicate average 
 times for the groups expressed in seconds. 
 
 Relation of Form Board Time to Learning, Age and Sex. 
 
 Age in 
 months 
 12 to 23 
 
 24*10 35 
 
 36 to 47 
 
 48 to 59 
 
 eotoT-i 
 
 72 to 83 
 84 to 89 
 
 Number of trials needed for learning, 
 4 5 6 
 
 Boys 
 
 Girls 
 
 Boys 
 
 Girls 
 
 Boys 
 
 Girls 127.0 
 
 Boys 62.0 
 
 Girls . 
 Boys. 
 Girls. 
 Boys. 
 Girls. 
 Girls. 
 
 65.9 
 
 27.0 
 31.7 
 
 60+lF. 
 75. 7# 
 73.0 
 33.0 
 
 24!5 
 
 22!o 
 
 107 +2F. 
 F. 
 
 28.0 
 28.0 
 
 2F. 
 
 23 
 F = Failure 
 
 F 
 
 145 
 F 
 
 2F. 
 
 Average 
 time 
 
 Age in 
 months 
 
 Boys. 
 
 Girls. 
 Both. 
 
 41.5 
 69.1 
 
 36 
 
 51.5 
 51.7 
 51.6 
 
 54.3 
 28.0 
 47.0 
 
 122.0 
 122.0 
 
 Relation of Form Board Time to Unlearning, Age and Sex. 
 
 Number of trials to develop unlearning. 
 3456789 10 
 
 12 
 
 Fail- 
 ures 
 
 12 to 23 
 
 fBoys 
 1 Girls 
 
 
 
 
 •• 
 
 •• 
 
 •• 
 
 •• 
 
 
 .. 2F. 
 .. 3F. 
 
 24 to 35 
 
 Boys 
 1 Girls 
 
 •• 
 
 
 
 107.0 
 
 •• 
 
 •• 
 
 145.0 
 
 
 .. 2F. 
 .. 2F 
 
 36 to 47 
 
 fBoys 
 1 Girls 
 
 
 
 
 99.0 
 
 F. 
 
 
 90.0 
 
 127.0 60+lF. 
 
 95.0 
 
 • 
 
 48 to 59 
 
 [Boys 
 Girls 
 
 135.0 
 
 
 
 32^4 
 
 38!o 
 
 33.0 
 
 67!5 
 
 20.5 .. 
 
 49.4 55.5 123.0 
 
 
 • 
 
 60 to 71 
 
 Boys 
 Girls 
 
 
 
 
 33.0 
 
 
 30.0 
 27.0 
 
 34!o 
 
 54.0 .. 
 
 .. 33.0 
 
 27 .'O 
 
 • 
 
 72 to 83 
 
 Boys 
 Girls 
 
 
 28.0 
 23.4 
 
 24.5 
 28.0 
 
 28.0 
 
 21^0 
 
 24.0 
 
 .. 39.4 .. 
 
 
 
 84 to 89 
 
 Girls 
 
 
 •• 
 
 21.0 
 
 24.0 
 
 •• 
 
 "f. 
 
 = Failure. 
 
 
 
 Average 
 
 Boys 
 
 135 
 
 28.0 
 
 53.5 
 
 28.0 
 
 31.5 
 
 86.3 
 
 58.3 39.4 .. 
 
 95.0 
 
 P. 
 
 Time 
 
 Girls 
 
 
 23.4 
 
 25.6 
 
 31.0 
 
 24.0 
 
 49.7 
 
 88.2 57.0 78.0 
 
 27.0 
 
 K. 
 
 
 
 ,Both 
 
 
 2i 
 
 5.7 
 
 42.3 
 
 30.0 
 
 27.8 
 
 68.0 
 
 70.3 62.6 
 
 61.0 
 
 V. 
 
STUDY OF CONDITIONED REFLEX 171 
 
 In studying the relation of Form Board times to the 
 rate of unlearning of an association we can see that in 
 general the rapid unlearners succeed more rapidly with 
 this task but the deviations are marked in both direc- 
 tions 
 
 The results obtained upon the Adaptation Board are 
 interesting in spite of the small number of cases. They 
 extend downward the results published by Goddard. 
 No child under thirty months of age succeeded in cor- 
 rectly responding to any one of the trials. No child 
 under 47 months of age completed the whole four turns 
 while no child over 77 months failed. In this inter- 
 mediary group success upon the first two trials is by no 
 means synonymous, as Goddard seems to think, with 
 success upon the third and fourth trials although it 
 may be in older children. Of the 33 between the ages 
 of 47 and 77 months 3 did only 1 turn, 8 did 2 turns, 
 3 did 3 turns, 10 did 4 turns and 9 failed com- 
 pletely. The correlation with chronological age is 
 -f- 0.703, which is surprisingly high when one considers 
 the few possible types of behavior in response to the 
 situation. The correlation with Binet age is -|- 0.716 
 and that with the Yerkes is + 0.672 with a slight su- 
 periority of the Binet evidenced as a means for study- 
 ing adaptability. This slight difference of the two is 
 also seen in a slightly higher correlation of the Yerkes 
 with the reverse function, unadaptative memory, as 
 measured by the Krasnogorski process of unlearning. 
 
 The correlation value of the adaptation board ability 
 with learning is — 0.366 and with unlearning is 
 — 0.280. The difference here, although slight, again 
 corroborates the fact that the learning and the un- 
 learning processes do involve adaptation as a factor 
 making for success. Disregarding age, which we have 
 
172 
 
 CHILD BEHAVIOR 
 
 seen is highly correlated with success on this test, we 
 find the relation of learning and unlearning to the num- 
 ber of successful turns on the Adaptation Board clearly 
 shown in the following tables : 
 
 Relation of Learning to Adaptation. 
 Number of trials needed for learning. 
 
 Boys 
 
 Girls 
 
 
 
 3 
 
 4 
 
 5 
 
 6 
 
 7 
 
 8 
 
 9 
 
 Failed... 
 
 
 2 
 
 
 2 
 
 2 
 
 2 
 
 2 
 
 
 Succeeded 
 
 on 
 
 
 
 
 
 
 
 
 Iturn... 
 
 
 
 
 
 
 
 
 
 2 turns.. 
 
 
 
 
 2 
 
 1 
 
 1 
 
 
 
 3 turns.. 
 
 
 
 1 
 
 1 
 
 1 
 
 
 
 
 4 turns . . 
 
 
 1 
 2 
 
 2 
 
 2 
 
 1 
 
 2 
 
 1 
 
 2 
 
 
 Failed... 
 
 
 2 
 
 Succeeded 
 
 on 
 
 
 
 
 
 
 
 
 1 turn... 
 
 
 2 
 
 1 
 
 
 
 
 
 
 2 turns.. 
 
 
 1 
 
 1 
 
 2 
 
 1 
 
 
 
 
 3 turns.. 
 
 
 
 
 
 
 
 
 
 4 turns.. 
 
 .. 
 
 2 
 
 6 
 
 1 
 
 
 1 
 
 
 
 Relation of Unlearning to Adaptation. 
 Number of trials needed for unlearning. 
 
 
 
 3 
 
 4 
 
 5 
 
 6 
 
 7 
 
 8 
 
 9 
 
 10 
 
 11 
 
 12 
 
 Failures 
 
 r Failed 
 
 1 
 
 
 1 
 
 
 1 
 
 1 
 
 1 
 
 1 
 
 
 
 4 
 
 Succeeded on 
 
 
 
 
 
 
 
 
 
 
 
 
 Boys 1 turn 
 
 
 
 
 
 .. 
 
 
 
 
 
 
 
 2 turns 
 
 
 
 2 
 
 
 
 
 1 
 
 
 
 1 
 
 
 3 turns 
 
 
 
 1 
 
 1 
 
 
 
 1 
 
 
 
 
 
 1.4 turns 
 
 .. 
 
 1 
 
 2 
 
 1 
 
 1 
 
 2 
 
 
 
 
 .. 
 
 
 (-Failed 
 
 
 
 
 
 
 
 1 
 
 2 
 
 
 
 5 
 
 
 Succeeded on 
 
 
 
 
 
 
 
 
 
 
 
 
 Girls 
 
 1 turn 
 
 
 
 
 
 
 1 
 
 1 
 
 
 1 
 
 
 
 
 2 turns 
 
 3 turns 
 
 •• 
 
 •• 
 
 1 
 
 •• 
 
 
 1 
 
 
 2 
 
 1 
 
 
 
 
 .4 turns 
 
 1 
 
 3 
 
 2 
 
 2 
 
 1 
 
 
 
 
 
 1 
 
 
 The tables merely confirm the low correlation coeffi- 
 cients indicating that in general the child who learns 
 more readily in the Krasnogorski learning is apt to 
 learn more readily to adapt to the changing situation 
 in this test, while the learning is still further condi- 
 tioned by the ability to unlearn which is essential for 
 adaptation. Or, it is the child who not only learns 
 quickly but who also unlearns quickly that is most apt 
 to do well on this board. 
 
STUDY OF CONDITIONED REFLEX 173 
 
 It is interesting to note that all boys who succeeded 
 in completing the first turn likewise did the second 
 turn while the two successes are not always correlated 
 in the girls. On the other hand the girls who do the 
 third turn all do the fourth turn also and this is not 
 true of the boys. Of course this may be only a chance 
 result from so few cases. 
 
 Regarding the three Healy Boards very little data 
 were obtained. The boards were not presented as a 
 learning problem in the manner Schmitt used them but 
 as a completion problem or task. As such they inter- 
 ested the children but errors and difficulty usually led 
 them to express a preference for the Seguin Form 
 Board. No successful completion was obtained from 
 any child under the age of 52 months. A girl of that 
 age completed the Foal and Mare Puzzle in 300 seconds 
 but failed on the other two boards. No other child 
 under 70 months of age was successful on the Foal and 
 Mare Puzzle. No child under 55 months of age com- 
 pleted Healy A and no child under 67 months com- 
 pleted Healy B. 
 
 On the Foal and Mare Puzzle only ten of the fifteen 
 children who were over the age of 70 months succeeded 
 nor is the failure definitely correlated with any other 
 process tested. 
 
 Similarly, eight children completed Healy A in times 
 ranging from 30" to 325", and nine, five that did the 
 Healy A and four others did Healy B in times rang- 
 ing from 90" to 330". The failures for children of the 
 same ages, mental ages, etc., are more frequent than 
 the successes, however. Consequently all that we can 
 decide is that success is indicative of an ability not 
 generally possessed by children of these ages but 
 whether failure is significant can not be determined. 
 
174 , CHILD BEHAVIOR 
 
 All of the cases worked either by chance or by the trial 
 and success method. 
 
 The other measurements of the children were of two 
 kinds : the purely anthropometric and the psychomotor. 
 The purely anthropometric measurements consisted of 
 the standing and sitting heights of the child and his 
 weight. The psychomotor measurements were the dyna- 
 mometric record the child achieved with his left and his 
 right hands used separately and his spirometer ability. 
 These are usually called the "grip" and the "vital" or 
 "lung capacity." These last are measured indirectly 
 through the use of apparatus and consequently measure 
 not the maximum efficiency of the muscles and the lungs 
 as such but the maximum efficiency of the child to vol- 
 untarily utilize the capacities inherent in his organism. 
 As this introduces a mental factor they are measures 
 which should probably correlate more highly with each 
 other than with the purely anthropometric findings. 
 This is actually the case. 
 
 The height and weight as such are less significant 
 than their relation to other measurements as indicated 
 by indices, hence we have made no detailed study of 
 them separately. The small number of cases would in 
 itself seem sufficient reason for not attaching any sig- 
 nificance to them as norms of height or weight, espe- 
 cially as all analysis would have to be by age and sex. 
 In studying mental processes, however, and psychomo- 
 tor functions, the thing we most desire to obtain is in- 
 formation concerning the relation of these measures to 
 psychomotor and mental growth. If they are at all 
 closely associated with the development of mental abil- 
 ity as tested by the various present-day procedures the 
 relation should appear when the two sexes are studied 
 together. 
 
STUDY OF CONDITIONED REFLEX 175 
 
 The following correlations with chronological age 
 were found: 
 
 Height, standing +0.898 
 
 Height, sitting + 0.908 
 
 Standing-sitting height index + 0.64)2 
 
 Weight + 0.894 
 
 Weight-height index + 0.673 
 
 Grip with right hand +0.871 
 
 Grip with left hand + 0.848 
 
 Average grip + 0.867 
 
 Grip-height index + 0.829 
 
 Grip-weight index + 0.844* 
 
 Spirometer ability + 0.862 
 
 Spirometer ability-height index + 0.827 
 
 Spirometer ability-weight index +0.762 
 
 Of these we selected several for further study and 
 correlation. The average grip was chosen instead of 
 either the right- or left-hand grip because it equates 
 the values for right- and left-handed children and since 
 it is the average of the best trial for each hand its 
 value is less apt to be influenced by chance factors. 
 The grip-weight and grip-height indices were also 
 studied because of their possible value as giving indi- 
 cations of physiological age while the spirometer-height 
 and the vital indices were studied for the same pur- 
 pose. 
 
 Average grip and the two grip indices may be con- 
 sidered together. The grip-weight index seems to be 
 slightly more valuable than either of the others as it 
 correlates slightly higher with the results of the mental 
 examinations. The grip indices invariably correlate 
 more highly with the mental ratings than do the vital 
 
176 CHILD BEHAVIOR 
 
 indices if we consider the Binet, Yerkes, Adaptation and 
 Form Board tests and the Krasnogorski unlearning 
 while the vital indices correlate significantly higher with 
 the Krasnogorski processes of learning, memory and re- 
 learning. This correlation with learning may seem to 
 be partly due to the fact that the use of the spirometer 
 involves more learning than the use of the dynamometer 
 but such can hardly be the case as the children were 
 given similar chance to improve their record on both 
 pieces of apparatus. The best record was used re- 
 gardless of the fact that it was the first or the last rec- 
 ord that the child made. 
 
 Grip records were obtained upon all of the children 
 over two years of age. The five under that age failed 
 seemingly because of lack of being able to understand 
 what was required of them and not because of their in- 
 ability to grip anything at all. The same children 
 failed to make any record upon the spirometer with the 
 exception of the one nearest to two years of age (22 
 months), who inhaled instead of exhaling. The record 
 was used despite this reversal of the normal way of mak- 
 ing a record but the other four who were all under six- 
 teen months of age could not even comply with the 
 suggestion to "suck it" or "taste it," which was given 
 in an attempt to get them to make a record by inhala- 
 tion after they had failed in an attempt to make one 
 by "blowing." 
 
 The average grip distribution is seen in Chart V. If 
 we take the average grip of the child and divide it by 
 his height we have the increment of grip per increment 
 of body height. The distribution of this index follows 
 regularly that of the grip itself, showing that the varia- 
 tion in the grip of the different children is due to some 
 other factor than that of physiological development as 
 
STUDY OF CONDITIONED REFLEX 177 
 
 measured by height, although height regularly in- 
 fluences the grip amount. This independence of the 
 factor of height is indicated by the unusually high cor- 
 relation coefficient of +0.989 between grip and the 
 grip-height index. Similarly the influence of weight 
 may be studied by calculating the increment of grip 
 per increment of body weight. 
 
 Body-weight seems to have a somewhat greater in- 
 
 CHARI V. AVERAGE DYNAMOMSTEH ABILITY AND ITS RELATION TO HEIGm, WEIGHT AHD AGE. 
 
 Pynamomoter atilily 
 
 Dytiaraometer atUity - Height Index 
 
 Bynamomeler ability - Welg>it Index 
 
 Caaee arranged numerically aceordlne to Increasing chronological age. 
 
 fluence upon the individual variations than height has, 
 reducing them and bringing them nearer to a group 
 average. Significantly enough it does not seem to raise 
 the relative rating of those whose grip was less than 
 the average as much as it decreases the variation of 
 those above the average. The grip-weight index has 
 in general the highest correlative value of the three 
 when we study their relation to the mental tests. The 
 sex diff^erences do not appear to be very great although 
 the girls seem more variable among themselves while 
 the range of variability is greater for the boys. 
 
178 , CHILD BEHAVIOR 
 
 The correlations between average grip and the learn- 
 ing and unlearning of the conditioned reflex are rather 
 low but on the whole the more rapidly a child learns or 
 unlearns the better is apt to be his grip or dynamom- 
 eter ability. There are many individual exceptions to 
 this generality and the relation is again influenced by 
 sex, age and by the high correlation the grip has with 
 things which indicate motor control. Grip or dyna- 
 mometer ability surely deserves a closer study and we 
 may some day find that its variation when the height 
 and weight factors have been eliminated will be contribu- 
 tive to a better understanding of the relation existing 
 between physiological and mental development. 
 
 The lung capacity as measured by the spirometer 
 gives a similar distribution to that found by the grip 
 measurements. The spirometer ability-height index or 
 increment of lung capacity as measured upon the spi- 
 rometer per increment of body height is, like the grip- 
 height index, quite similar to the original measurement 
 when the factor of height had not been eliminated. 
 This can easily be seen in the close approximation of 
 the two curves on Chart VI. The lung capacity-weight 
 index is quite diff^erent. The weight seems to be a de- 
 termining factor in the increase of lung capacity in 
 the children over five years of age. It also influences 
 the variations of individual cases. 
 
 The lung capacity- weight or vital index has been 
 rather widely used. DeBusk (36) finds that children 
 who are retarded show a lessened vital index. Since 
 then he has also declared that there is a definite rela- 
 tion between the vital index and mental age according 
 to the Binet although he has presented no correlation 
 coefficient (Unpublished doctorate thesis). 
 
 There is a correlation of -j- 0.739 between the vital 
 
STUDY OF CONDITIONED REFLEX 179 
 
 Index and the Binet age of the children measured in 
 this study. The correlation coefficient of the lung ca- 
 pacity-height index with Binet age is even higher, be- 
 ing -\- 0.769. But neither of these is as high as the 
 correlations between grip and Binet rating. 
 
 The same is true of the Point Scale or Yerkes rat- 
 ings. The correlation coefficient with vital index being 
 + 0.679 while that with the lung capacity-height in- 
 
 CHART VI. SPIPOMBTER ABILITY ASD ITS RKLATiOIf TO HEIGHT, VEICHT AST) ACS. 
 
 XX ~ ""j 
 
 4 __ Splrnm-t.T ahnity 1 1 X 
 
 Spirometer ability - Height Index JH 
 
 3 __,_ Splroaeter ability - Weight IndAic ^ • 
 
 
 ^ - "- ~ :^ .-^IX " " 
 
 11 A. Ik t '•' 
 
 1 •• tt 1^ f 
 
 : : -:• _u iW-il ' ■:% 
 
 X- ii tij ■ " >• 
 
 lIl :. UtiX U I ^ . 
 
 9 - - ^^ :• :.:\^n-TV~ T -i 
 
 - - -- It ^^A%^-^w--'t - i li 
 
 8 - -Z ■ ■ l\^ LL^^.lWltZ JJ 
 
 ■1 1 ■ -1^ : X3 4-4^ 
 
 
 ;^ : "V V - -i* -- ffen 1: 2t ~! ^ 
 
 6 - ■■ Ui- • \ " ilLa-. Ml Zl n /. I X 
 
 : z 2^ z i:i.i^ I ^zit^p % v --^^ -^ ■ -izt^ 
 
 5 ^S . EE 25 I ^ 'I I-"t-!l ^Z OZlA ■ "^7 t".' 
 
 zt- -1^1 -^^^ 7\u ZMh^ L XX "^^ ••: 
 
 4 ^i-x^LW:^^\_^S tizit - --i ' It 
 
 33 2- -"^^ItX _. 11 
 
 3 tX-f^'^ X 1^ X J 
 
 -•••■J:x : zL^ z' 
 
 2 :^.^a:x 
 
 ■z^y X j- 
 
 1 1 X " 
 
 - t X ~ _ " ± "" 
 
 _i:Sg_ ,_ _ _. _ _„__ 
 
 0*868^ arranged 
 
 5t-a)o.Of-iMio<'««r-«>o>Or-iNiO'*w52-»goHo!(02;; 
 ^Hr^r^lNc^NNc*PJM(\lo^cllOtom>oto■o«««rtlO«J•«I■v«■^^■■ 
 
 numerloally aoeordincr to Incrcaslns chronological ege. 
 
 10 C- 00 o. o 
 
 dex it is -f 0.722 and with the grip-weight index it is 
 + 0.755. 
 
 There are moderate correlations between the vital in- 
 dices and Form Board and Adaptation scores but in 
 general these are not so high as the correlations of the 
 same scores with the grip indices. 
 
 The Krasnogorski learning and the vital index have a 
 correlation of — 0.548 or there is a tendency for the 
 more rapid learners to have a greater spirometer abil- 
 ity-weight index. The correlation coefficient for learn- 
 
180 CHILD BEHAVIOR 
 
 ing ability and spirometer ability-height index is al- 
 most as high, being — 0.516. On the other hand the 
 correlation coefficients expressing the relations between 
 these indices and unlearning are so low as to be prac- 
 tically negligible. 
 
 On the whole the correlation coefficients indicate that 
 both of these indices as well as the grip indices should 
 be used as supplementary tests of mental behavior. 
 
 RESULTS OBTAINED UPON DEFECTIVES 
 
 In regard to the question as to whether Krasnogorski 
 was right when he claimed that the results obtained by 
 his method have such high clinical value we must turn 
 for a specific answer to our experiments upon mental de- 
 fectives. The fact, pointed out above, that in our un- 
 selected group the children found at the extremes of 
 the age distributions for boys and those found serially 
 misplaced by Binet or Yerkes, when the basis of group- 
 ing was the number of trials on the learning process, 
 are the deviates of the group as a whole — this fact 
 shows that we have a method which is able to help de- 
 termine defectives. Whether it can do so independent 
 of correlation with other findings is another matter. 
 
 The work upon the seven lower-grade defectives will, 
 with the exception of cases 6 and 7, throw very little 
 light upon the problem. The rate of learning of the 
 first five cases is as foUows : 
 
 Case 
 
 No. 
 1 
 
 Age in 
 
 No. 
 
 of trials for 
 
 Mental Age 
 
 months. 
 
 
 learning 
 
 in Years. 
 
 55 
 
 
 14 
 
 1— 
 
 50 
 
 
 5-6 
 
 1 
 
 51 
 
 
 13 
 
 lor 2 
 
 60 
 
 
 10-19 
 
 12 
 
 36 
 
 
 6-9 
 
 13 
 
STUDY OF CONDITIONED REFLEX 181 
 
 Two of these establish a reaction within the range 
 of number of trials found upon our unselected group. 
 Their reaction is nearer that which one would expect 
 of their chronological age than that which corresponds 
 to the same mental age in our imselected group. The 
 other three are far slower learners than the youngest 
 normal children tested. But then such a test is not 
 actually needed as all of the five are so definitely idiotic 
 that a superficial examination reveals the hopelessness 
 of the condition to a chnician of ordinary experience. 
 Case seven is somewhat higher grade but again defi- 
 nitely defective. He learns in 8 trials on one process 
 and in 12 on another. The greatest number of trials 
 used by any of those in our unselected group of chil- 
 dren who are over 37 months is 7, Case 7 needs 8 and 
 in mentality he belongs about with the three-year-olds 
 who need seven or eight trials, although he is 73 months 
 old. Case six is only 34 months old, but unlike our 
 normals of that age who require about 7 or 8 trials 
 he needs 18 to form an association. One feels by this 
 comparison that the diagnosis of "imbecile" made on 
 him is all he can ever fulfill, although by other tests he 
 is at present practically normal. 
 
 The seven children in the Waverley Institution who 
 tested nearest to normal give us more valuable data 
 although the number is unfortunately small. Neverthe- 
 less it is an unselected group since all those available 
 under 8 years of age were used, being 6 boys and one 
 girl. The six boys ranged in age from 57 to 93 months. 
 The girl was 81 months old. Three of these tested "at 
 age" on the Binet and were on observation with diag- 
 nosis deferred. Of the other four three were one year 
 and one was three years backward by Binet. 
 
18^ CHILD BEHAVIOR 
 
 The following table shows the condition fairly well 
 
 Distribution of 7 Borderline Defectives. 
 
 Age Binet Point score on Krasnogor ski Processes Institntion 
 
 Case in Age Binet Yerkes Learn* Recall Un- Re- Diagnosis 
 
 months ing learning Itarning 
 
 A 84 41 16 10 3 3 16 2 Imbecile 
 
 B 70 
 
 41 
 
 17 
 
 9 
 
 5 
 
 2 
 
 8 
 
 2 
 
 Moron 
 
 C 89 
 
 61 
 
 26 
 
 25 
 
 8 
 
 2 
 
 15 
 
 2 
 
 Moron 
 
 D 59 
 
 33 
 
 14 
 
 5 
 
 5 
 
 3 
 
 11 
 
 2 
 
 Deferred 
 
 E 67 
 
 42 
 
 17 
 
 9 
 
 6 
 
 2 
 
 14 
 
 2 
 
 Deferred 
 
 F 93 
 
 72 
 
 32 
 
 37 
 
 5 
 
 2 
 
 14 
 
 2 
 
 Deferred 
 
 G(girl)81 
 
 61 
 
 27 
 
 25 
 
 13 
 
 7 
 
 8 
 
 2 
 
 Probably F. M, 
 
 From this we see that with one exception the defec- 
 tive boys learn just about as well as the boys in our un- 
 selected group. Indeed, three out of the six learn in 
 five trials which seems to be the mode for the unse- 
 lected group also. One defective, however, uses eight 
 trials. He is 89 months old and tests 26 points by 
 the Binet. None of our unselected group of children 
 who was over 37 months old or who tested more than 
 16 points on the Binet was so slow in forming a con- 
 ditioned reflex. When we add that the same boy needed 
 15 trials to unlearn the conditioned reflex it is even 
 more obvious that he lies without the normal group. 
 
 This diff'erence in the ability to unlearn the condi- 
 tioned reflex is marked in the majority of cases. Only 
 two of the seven develop unlearning in a number of 
 trials which is small enough to lie within the normal 
 range of variability. The normal range is 3 to 12 
 trials. One of the defectives develops the unlearning 
 in 8 and one in 11 trials. Both of these are below 
 what they should be on the Binet. This seems more 
 than a chance relation when we consider that of the 
 boys in our unselected group who were of equal age 
 the only ones needing more than 7 trials were the son 
 of the woman with the goitre, who took 8, the defec- 
 tive boy, taking 9, the son from the family with glandu- 
 
STUDY OF CONDITIONED REFLEX 183 
 
 lar disturbances using 10, but of these three only the 
 defective boy was below by Binet while five boys be- 
 tween 32 and 51 months of age, normal, with 12-24 
 points on the Binet, use 8-12 trials. 
 
 The one girl tested seems evidently very abnormal — 
 using 13 trials to learn, needing seven to recall and 
 then eight to unlearn. In spite of the fact that she 
 is bright, attractive and playful the experimenter per- 
 sonally feels that these three processes give definite evi- 
 dence of her mental deficiency as well as of that of the 
 six boys, although they all appeared to deviate but 
 little from normals on the various Form Boards, etc. 
 
 Two other children who were available were studied. 
 These were brothers who had been taken to a public 
 clinic for mental examination because they were "not 
 getting along well in school." They were diagnosed 
 as "not feeble-minded." They are 85 and 75 months 
 old respectively. The family is of rather low mental- 
 ity even for that of an unskilled laborer and the moth- 
 er's relatives are all of greater ability, tending to- 
 wards the lower professional class. The mother her- 
 self is good natured and easy-going but cleanly and 
 she evidently makes the most of her husband's scanty 
 wages in caring for five growing children. The father 
 seems stupidly intelligent but without any definite vir- 
 tues or vices. His mother is reported to have suffered 
 from a disease of long-standing which from descrip- 
 tion could be nothing but syphilis. The three other 
 children, girls, are rather nervous, high-strung and ex- 
 citable but are not feeble-minded although the one who 
 is in her thirteenth year has begun to fall back from 
 leading her class and has had chorea. The other two, 
 twins, are seemingly normal but similarly neurotic. 
 
 The older of the two boys, 85 months old, scored 32 
 
184 CHILD BEHAVIOR 
 
 points by Binet, 29 by Yerkes, did the Form Boards 
 readily but if told to hurry became erratic in his move- 
 ments ; was up to the normal averages in his grip and 
 lung capacity. He developed the conditioned reflex 
 in 4 trials, recalled it in 2, developed unlearning in 
 7 and releamed in 2 trials. These records are all with- 
 in the normal range. He has had a great deal of ill- 
 ness since early childhood, and is threatened with tuber- 
 culosis of which he has all the gross signs. He has 
 a spinal curvature, spay-foot, is chicken-breasted, has 
 a very high palate, is generally anaemic and has had nine 
 peritonsilar operations. This seems sufficient to ac- 
 count for his rather poor school work without implying 
 any absolute mental defect but with imperative indica- 
 tions that the problem is a physical one. 
 
 With the brother 75 months of age the case is dif- 
 ferent. He is and always has been healthy. He is, for 
 his age, unusually large, especially when he is com- 
 pared with the rest of the family in development. On 
 the Binet he scores 6^ years or 27 points, while on the 
 Yerkes he scores 25 points. He does the Form Board 
 well, fails on the two harder turns of the Adaptation 
 Board and completely on the Healy Boards. He takes 
 7 trials to develop the conditioned reflex, recalls it in 
 2 and then requires 21 trials to unlearn it although he 
 then re-learns it in 2. It is not difficult, keeping these 
 facts in mind, to see why, although he is not feeble- 
 minded by the Binet or Point Scale, he may be actually 
 impossible so far as school improvement goes. School 
 is the prolonged test of social efficiency and ability to 
 adapt and learn which is given all children. 
 
 This boy has the ability to form the conditioned re- 
 flex or association as readily as normal children but 
 when this simpler situation is complicated by a new 
 
STUDY OF CONDITIONED REFLEX 185 
 
 condition he can not adapt readily to the new condi- 
 tion but his old useless reaction hangs on in its initial 
 form. This gives us sufficient insight into his mental- 
 make-up to enable us to see readily why he is a school 
 failure. He can pick up bits of knowledge, form asso- 
 ciations, remember impressions, but he can not utilize 
 these experiences in the production of purposive and 
 effective reactions in situations which vary constantly. 
 The reason for his failure lies in his inherent neural pre- 
 disposition or "set." Because of this he fails on the 
 real mental test of acquiring an education. The ex- 
 perimenter does not doubt in the least but that he will 
 eventually prove defective by other mental tests when 
 sufficient time has elapsed for him to have reached his 
 limit of development. From experience with the other 
 group of borderline cases it seems probable that he 
 will eventually prove ta be about of the low-grade mo- 
 ron type. 
 
 DISCUSSION AND SUGGESTIONS 
 
 The mere execution of a piece of experimenting, such 
 as the writer has tried to carry out, tends to the de^ 
 velopment in the experimenter of certain "attitudes" 
 towards the problem both as regards subject matter 
 and technique, while usually certain more general points 
 of view develop seemingly unassisted. The statement 
 of these, in so far as they would affect further work 
 by the experimenter, should be considered an essential 
 part of the exposition of the problem. 
 
 The first condition of successful work with young 
 children is, in my opinion, a real interest in child life 
 and a knowledge of how to handle children in the thou- 
 sand and one exigencies of a morning's experience with 
 them. To be able to give drinks of water, wash hands, 
 
186 CHILD BEHAVIOR 
 
 tie up bumps, prevent quarrels and return the chil- 
 dren to their homes without any signs of physical or 
 mental disturbance is fundamentally a test of ability 
 to handle them under experimental conditions. Women 
 have an undoubted advantage in this field and partly 
 for these reasons. The future of Child Behavior seems 
 to the author intimately bound up with the recognition 
 of this superior fitness of women for such investiga- 
 tions. Needless to say such fitness is only one prerequi- 
 site and can not be expected to replace exact training 
 in experimental methods. 
 
 And now regarding the children themselves. It is 
 fundamentally necessary to consider their state of 
 health or fatigue, and their emotional attitude towards 
 the experimenter and the experiment as well as to gath- 
 er the actual results upon the problem in hand. The 
 problem of health can be treated either by eliminating 
 all children who are ill or by noting the condition and 
 observing its effect upon the results obtained. Fa- 
 tigue is a large and serious problem. In this study 
 all children were used between nine and half-past eleven 
 in the morning, the younger or delicate children on a 
 given day being used first. Fatigue symptoms were 
 never present in any marked degree in the unselected 
 group. Probably the stimulation of the novel situa- 
 tion rendered them less liable to fatigue. It appeared 
 in a marked degree in the child worked with through 
 a number of weeks. 
 
 The emotional attitude can usually be kept favor- 
 able. It is far better to tell the child that you will 
 allow him to come and play with your playthings than 
 to beg him to be a good boy and come. Most children, 
 and indeed I know of no exceptions, are as delighted 
 to see the queer new things in a laboratory as they 
 
STUDY OF CONDITIONED REFLEX 187 
 
 are to go to the circus. Then, when they have come, 
 this interest can easily be maintained by a deliberate 
 presentation of all work as a game, a play, a puzzle 
 or a challenge. The time limit becomes a deadly enemy 
 to be beaten, often objectified as the racing hand of 
 the stop watch. An incredulous "No, I don't believe 
 you can do it again" will be sufficient motivation for 
 a second attempt of a difficult task from which interest 
 departed as soon as it was solved. One little girl of 
 four failed upon the Seguin Form Board and said, "The 
 blocks wouldn't stick." Five minutes' play in which 
 we "made believe" paint them with glue to make them 
 stick led to self-confidence, intense effort and joyous 
 success. In another instance everything done had to 
 be put down on paper in a wonderful system of hiero- 
 glyphics so that the successes could be remembered "to 
 tell father." All this takes time but it is more than 
 worth while. 
 
 The Aussagen or "free reports" of the children which 
 denote their attitude towards the experiment are well 
 worth jotting down, even though one may make none 
 but a personal use of them. For instance, the attitude 
 of the children towards my experiment was largely one 
 of their attitude towards the feeding. A number of 
 them said "Oh, it's candy," "It's fudge," "It's sweet," 
 when first fed but by far the greater number of these 
 verbal reactions came during the first few trials of the 
 period when I was attempting to develop unlearning. 
 Some of them only smiled sheepishly or looked at me 
 shyly when the bandage was taken off without candy 
 having been given. Several asked, "Is the candy all 
 gone.?" "Won't I get anj^ more to-day?" while one lit- 
 tle girl offered to go to the store and buy me some 
 more. Another little fellow broke out into an unusual 
 
188 CHILD BEHAVIOR 
 
 stutter and said, "You-you-you forgot to give me the 
 candy that time." Another counted, "That's two times 
 I didn't get any, this is three times." Others contented 
 themselves with stating, apparently to the ceiling, that 
 they liked candy. One impudently begged, "Give me 
 just a little bit this time, won't you.''" Another stated 
 circumspectly, "I opened my mouth that thne" and then 
 on the next trial, "I opened my mouth again" but, when 
 I asked why, she said, "I don't know," although her 
 confusion and shy changing of the conversation indi- 
 cated that she probably was attempting to give me an 
 indirect intimation of her desire for candy. The in- 
 sight these reactions give makes interpretation ob- 
 viously unnecessary. 
 
 The number of cases used in this study is far too 
 small to give results which can be accepted as abso- 
 lute and final and I desire to make no dogmatic asser- 
 tion of the manner of functioning of the conditioned 
 reflexes in children in general. A group of 50 even 
 with the control groups of defectives is far too small 
 and no one wishes more than I that the number were 
 5000. I believe that a more extensive study will show 
 that the functioning of the conditioned reflexes is in- 
 fluenced by even more factors than I have been able 
 to indicate. Consequently these results are presented 
 as suggestive and all contradictory evidence is cheer- 
 fully invited as that will mean more intensive and ex- 
 tensive study of young children. 
 
 The sex differences which I have discussed a num- 
 ber of times in this chapter may be thought to be mere 
 interpretations of insufficient data, introduced because 
 of the writer's personal bias or interest. Quite the re- 
 verse is true. All of the first analyses of the findings 
 were made without separating into sex groups. It did 
 
STUDY OF CONDITIONED REFLEX 189 
 
 not seem probable that in a group of fifty children all 
 under the age of eight there would be sufficient differ- 
 ence to make it worth while considering boys and girls 
 separately. However, when all other factors had been 
 accounted for there were still irregularities in the dis- 
 tributions which could not be accounted for but these 
 disappeared when as a last resort the two sexes were 
 considered separately. 
 
 A point which may be of interest to clinical psycholo- 
 gists is the fact that in every instance the observation 
 of the child during the experiment gave reactions visi- 
 ble to the eye in the same trial as their earliest develop- 
 ment showed in the kymograph record. Indeed often 
 the record showed a curve due to cough, a laugh, a 
 shrugging or twisting of the head which could only be 
 understood because the child had been closely watched 
 and because after each trial, his general behavior had 
 been written down. Very often the exact situation was 
 more vividly expressed by the general body position, 
 tension and deep breathing than by the mouth opening 
 itself. For clinical purposes one might easily apply the 
 method without any apparatus. 
 
 I have made no attempt to evaluate the curves re- 
 cording the reactions. Krasnogorski explains his 
 curves as representing first a mouth opening and then 
 succeeding that a series of swallowing movements. My 
 results were not so uniform. With some children this 
 type of reaction appeared but with others the mouth 
 would open two or three times with swallowing move- 
 ments interspersed. In other cases the mouth would 
 be opened wide, gradually closing, and the swallowing 
 curves would be scattered along this decreasing curve. 
 In others breathing was so violent as to give an addi- 
 tional complicating factor in the curves while with 
 
190 CHILD BEHAVIOR 
 
 others lip movement (not recorded) was the chief re- 
 action and the swallowing movements were very faint 
 and mouth opening entirely lacking. 
 
 The use of so many auxiliary means of studying the 
 child perhaps needs further emphasis. If the study 
 of young children is to lead us to a factually based 
 concept of the child's behavior all of the facts ascer- 
 tained regarding him must be empirically welded into 
 a synthesis. This can not be done if we completely 
 isolate the study of any one process from that of all 
 others. Hence each study undertaken should involve 
 at least two distinct processes and the results obtained 
 from the two should be correlated. Another experi- 
 menter by selecting one of these processes and a new 
 one can thus not only contribute new data but he has 
 a means of correlating all of his work with that of 
 the first investigator. 
 
 Another just as important reason is the need of 
 knowing about any one child all the factors which may 
 influence the results. For this purpose social condi- 
 tions, heredity, sex, age, general health, and as many 
 other items as possible should be considered. Kras- 
 nogorski may have considered these but he presents no 
 data. He claims a clinical significance for the condi- 
 tioned reflex but does not present his criteria. If the 
 cases he used were already defective enough to be diag- 
 nosed without this method little benefit accrues from 
 it. Consequently in this study the variety of proce- 
 dures used has a double purpose. 
 
 It makes an attempt to begin a correlative study of 
 the measures usually applied in the study of any child 
 with the aim of placing him relative to his group. It 
 also gives a number of evaluations of each individual 
 child which enables one to more clearly analyze out the 
 
STUDY OF CONDITIONED REFLEX 191 
 
 possible factors determining why he holds this or that 
 place in the group. Because of the former need the 
 correlation coefficients of the various tests have been 
 calculated. The second usage is illustrated in the in- 
 dividual case illustrations where an explanation of a 
 varying factor in one process aids in interpreting devia- 
 tions within the group when it is studied from the 
 aspect of some other process. 
 
 This latter point is beautifully illustrated in the case 
 of children in the same family. There are individual 
 conditions as well as the family and social conditions 
 affecting both alike. Differences which remain when 
 age and sex have been evaluated can hardly be attrib- 
 uted to "just individual differences" any more logi- 
 cally than they can to chance errors of experimentation 
 unless we find the same variation in other corroborating 
 findings and these can not be picked up by chance after- 
 wards but must be a part of the original data. 
 
 The opportunity of studying children under one year 
 of age was lacking in the village where the unselected 
 group was observed. Consequently it resolves itself 
 into a separate departure which the author has not yet 
 attacked. Krasnogorski states that the conditioned 
 reflex can with difficulty be established in the second 
 half year of life but not until then does it reach its 
 functional perfection. This arbitrary determination 
 of a starting place seems either a conclusion based up- 
 on a few failures, probably under unpsychological con- 
 ditions, or else it may be a logical deduction. Present 
 knowledge of child development would tend to lead in- 
 stead to a belief that the ability to form some kinds 
 of associations is present in some degree from the time 
 of birth. The development of the association may be 
 more difficult, that is require more trials, and it may 
 
192 CHILD BEHAVIOR 
 
 not be possible within the first day or two due to the 
 enormous adaptive changes taking place within the 
 organism. But this very potentiality for adaptation to 
 the new environment is a type of learning and promises 
 interesting results. Moreover, plenty of evidence has 
 been found by observation and in the biographical and 
 genetic studies. 
 
 When a child has learned to stop the hungry cry 
 first when he feels the breast, later when he is picked 
 up and still later when he is spoken to this is a con- 
 ditioned reflex. The touch or sight stimulation is a 
 conditioned stimulus and has been associated with the 
 feeding. Such associations are reported in very young 
 children by Preyer, Stern, Shinn, Mrs. Hall and Dear- 
 born, while the writer observed a conditioned crying 
 in a child 10 days old, fed, warm and dry, who cried 
 until taken up and held and who repeated crying as 
 soon as he was laid down. It was reported that this 
 had happened at the same time each day since the 
 seventh day. 
 
 The use of abnormal and borderline cases together 
 with an unselected group seems doubly advantageous 
 to the writer. If a process is fundamentally necessary 
 for normal functioning there should in all probability 
 be greater deviations from the norm among defectives 
 than in the unselected group. The "edges" of the two 
 should, in all probability, overlap. If the process is 
 so generally non-variable that it is the same in de- 
 fectives as in normals we must evaluate it less highly 
 in the normal child and seek elsewhere for an explana- 
 tion of why all are not equally gifted. 
 
 The question might easily be raised as to why the 
 results are not compared in detail with the results 
 obtained in other studies. For instance, this study in- 
 
STUDY OF CONDITIONED REFLEX 193 
 
 dicates a direct relation between learning and effective 
 retention. This is in agreement with the findings of 
 Henderson (76), who used meaningful material. He, 
 also, as I have, found that the older subjects tended 
 to learn more rapidly than the younger ones. Nors- 
 worthy (123) also finds the rapid learner retains bet- 
 ter and Busemann (M) is inclined to accept this view 
 while Lyon (111) not only confirms this point but 
 finds women and girls do better on initial learning while 
 men and boys retain better. However, he finds many 
 exceptions for "illogical" material. All of these 
 studies as well as those on inhibition have been made 
 on older subjects and have used verbal Aufgaben and 
 chiefly verbal learning material. This study differs not 
 only in the age of subjects but especially in method 
 and material. Consequently minute comparisons are 
 left to the reader interested therein. 
 
 The principle underlying experimentation with the 
 conditioned reflex is, however, not as different from 
 that usually employed in the learning process as it ap- 
 pears at the first glance. In the learning process both 
 nonsense syllables and meaningful words are used. 
 These are always grouped and a single task may in- 
 volve 10, 12 or, it may be hundreds of units. In the 
 study of the conditioned reflex this task is simplified. 
 The child learns only one unit. The stimulus is one 
 that is arbitrarily chosen and is undoubtedly meaning- 
 less to the child from the standpoint of our idea of 
 the reaction to be developed. Meaning gradually ac- 
 crues, that is new associations are formed between the 
 sensations from the conditioned stimulus and other 
 sensations and responses. Because of this simplification 
 of material the determination of retentiveness combines 
 easily the method of saving with that of the determi- 
 
194 CHILD BEHAVIOR 
 
 nation of retained members. The stimulus is applied. 
 If the reaction occurs at once the member is retained 
 but if it does not occur the chocolate "help" is given 
 again and relearning is begun. Thus sub-liminal traces 
 are as easily and accurately evaluated as actually re- 
 tained associations. 
 
 The voluntary comments made by the children indi- 
 cate that the stimulus rapidly develops meaning for 
 them. The meaning appealed to is the most funda- 
 mental one of a living, growing organism — food. This 
 appeal probably facilitates learning and it may be that 
 it increases the ease of retention. Consequently a new 
 series of problems opens up at this point. The method 
 probably is the only one we have to-day which offers 
 a chance to study meaning and affective values in young 
 children. The relative values of food eaten, seen, 
 touched, mentioned; of pleasant, unpleasant and new 
 stimuli ; of commendation and actual reward may easily 
 be studied simply by varying the stimulus quality, in- 
 tensity or modality. 
 
 And now a few words more about the more general 
 uses of the method. It is easily applicable with very 
 young children. It is independent of the acquisition 
 of speech and hence enables one to study the develop- 
 ment of mental processes without considering the lan- 
 guage factor. It can however be linked up with speech 
 studies in various ways. For instance, an auditory 
 stimulus may be used as the conditioning stimulus. 
 This may just as easily be a nonsense syllable as the 
 ringing of a metronome. It might even be possible 
 to develop discrimination of nonsense syllables by using 
 feeding when one is said and not with the others. The 
 relative value of auditory, visual, cutaneous, motor and 
 thermal stimulations may be sfepdied by comparing the 
 
STUDY OF CONDITIONED REFLEX 195 
 
 length of time necessary to develop conditional reflexes 
 to each of these. Naturally this must be done in one 
 and the same child and as there may be a transfer of 
 attitude or attention from one series to another the 
 series must be studied in various children in different 
 orders of development. Sensory discrimination and 
 specificity and memorial functioning of stimuli of va- 
 rious modalities may also be studied and may throw 
 some light upon the better modalities of presentation 
 for best learning and retention. The verbal Aufgabe 
 may be introduced and its efi^ect show relatively. Both 
 the negative and positive Aufgabe may be studied thus. 
 So far as an investigation of the factors influencing 
 the learning process is concerned this method allows 
 of such wide variation that time factors, eff^ect of fre- 
 quency and distribution of stimulations, of intensity 
 and complexity of stimuli, of modes of presentation, 
 quality of stimuli, of eff^ect of afl^ective toning, near 
 and distance stimulation may all be studied while the 
 child thinks he is playing a game. 
 
CHAPTER VIII 
 
 CONCLUSIONS 
 
 T HAVE tried to present briefly the facts which a 
 "■• survey of child study gives, disregarding details 
 but stressing in a broader more synthetic fashion the 
 factors influencing its development. 
 
 Child study has been the outcome of a new conscious- 
 ness in the race and society which has focused upon 
 the child as its most valuable asset. The first studies 
 made of the young child were motivated primarily by 
 ethical, moral, religious and educational aims. Not 
 the child's abilities or unfolding mental processes as 
 such were the object of study but they were regarded 
 as means of giving him training and education. The 
 study of the child as such, for his own sake, was not 
 properly emphasized by any one before Schleiermacher. 
 Even after his formulation of childhood for the sake 
 of the child it took many years, a quarter of a cen- 
 tury in fact, before we find any expression of interest 
 in the child's person, his body and mind, motivated by 
 a purely scientific desire for a better knowledge of the 
 child himself. 
 
 Then in the work of Sigismund, Kussmaul, and their 
 followers comes the beginning of careful observations 
 of child nature. These studies do not, however, issue 
 from psychological or educational circles but are the 
 work primarily of physicians. Physiological methods 
 and theories were sufficiently well evolved to permit in- 
 
 196 
 
CONCLUSIONS 197 
 
 vestigation of physical functions. Psychology had not 
 yet developed far enough to have even a method that 
 might be used for any such studies. 
 
 As psychology gradually devised its experimental 
 methods these were based largely upon introspection 
 and the study of the young child seemed consequently 
 limited to observation. This was considered a handi- 
 cap and for some time undoubtedly proved a rather 
 effective deterrent to quantitative experimental studies 
 under controlled conditions. Nor had these as yet 
 evolved their independent procedures. This tendency 
 to observational study of children was also favored 
 by the difficulty of gaining permission to study any 
 large number of children during the years before the 
 kindergarten age. In this early period the social 
 group of the child is that of the family and he is not 
 segregated with a large number of his kind unless he 
 is in an abnormal physical or mental condition and 
 committed to a hospital or institution. 
 
 With the added impetus and suggestion given by the 
 popular interest in evolutionary theory, genetic or de- 
 velopmental studies were vigorously and assiduously 
 compiled. The external expressions of the child 
 through language were also studied both from a gene- 
 tic standpoint because of the interest in his develop- 
 ment of the language function and also from the stand- 
 point of indirect observation because it was assumed 
 that his use of language gave a fair index of his men- 
 tal processes. For the first purpose the studies were 
 usually intensive and of only one or two children and 
 mostly made during the first three years of life while 
 for the latter they tended to become contributive to 
 education and the subjects were usually children of 
 five or six years of age who were just entering school. 
 
198 CHILD BEHAVIOR 
 
 The intermediate period of two or three years re- 
 mained almost entirely unexplored. 
 
 The child's movements were also used as a means 
 of studying his mental processes. For instance : grasp- 
 ing was made a means of studying color discrimina- 
 tion and color preference. These studies most nearly 
 approximate the requirements of scientific experimen- 
 tation, allowing of control of conditions and giving 
 easily evaluated results but their use seems limited to 
 a very narrow field. 
 
 Individual studies have not been confined to these 
 fields of physiological psychology, language and motor 
 development but have touched almost all subjects per- 
 tinent to psychology. As a whole, however, either the 
 number of children used has been very small, the method 
 faulty or the findings so mixed up with inference and 
 discussion that the results are equivocal from the 
 standpoint of their empirical value. The psychogenetic 
 or biographical studies were and are valuable. They 
 have been the pioneer path-breakers that indicate the 
 extent of the problem confronting us but now exact 
 definitization of facts demands quantitative studies un- 
 der controlled experimental conditions and an unbiased 
 presentation of the results obtained. 
 
 Some such experimental investigations have lately 
 been made by those interested in Comparative Psy- 
 chology. They have used various of the objective 
 methods upon children with rather favorable results. 
 In so far as they have been interested in animal rather 
 than human psychology their work shows unmistakable 
 errors. Although making comparisons of the results 
 obtained upon children and other animals they intro- 
 duce great variants in procedure when dealing with 
 the two. The verbal Aufgabe with children takes the 
 
CONCLUSIONS 199 
 
 place of objective sense stimuli used with the animals 
 or if objective stimuli are given they are such as appeal 
 differently in the two cases. The number of children, 
 with the exception of Katz' studies, is very small. In 
 general, the reports show that the experimenters were 
 working with inadequate and often erroneous ideas of 
 what the child as a type means. 
 
 This attempted use of purely objective methods in 
 the study of the child's behavior is a decided advance, 
 however, for errors in technique can easily be remedied 
 and, although most of the methods used so far have 
 been rather unwieldy and cumbersome, we can see now 
 the theoretical and objective basis from the use of 
 which the experimental psychology of the young child 
 will rise. This new attitude towards the child con- 
 ceives of him as an organism peculiarly adapted to 
 growth and functional responses to the external stimuli 
 among which he lives. Our information concerning this 
 organism, its peculiarities and abilities, is best in- 
 creased by studying the variations of its behavior un- 
 der controlled or definitely ascertained conditions of 
 stimulation. These variations may be changes in be- 
 havior of growth and structure formation or they may 
 be changes in function. The study of the latter 
 changes in so far as they relate to or are neural in 
 character is peculiarly the property of psychology. 
 These changes are not, however, to be thought of as 
 existing independently of or uninfluenced by the charac- 
 teristics of the organism considered as a whole. 
 
 The chief impetus towards the formulation of this 
 concept of the psychology of the infant has come from 
 the Pavlov school, especially as it has been applied to 
 human beings by Bechterew and Krasnogorski. The 
 work of Bechterew, followed by that of Watson in 
 
200 CHILD BEHAVIOR 
 
 this country, is less significant for the study of the 
 young child than is that of Krasnogorski. Most of 
 Bechterew's work has been developed upon the punish- 
 ment motivation to protective response. In children 
 this induces attitudes towards the situation which are 
 absolutely antagonistic to the purpose we have in mind 
 of studying the child's reactions under normal condi- 
 tions. 
 
 Krasnogorski more nearly fulfills the demands our 
 concept of the child makes upon us. His assertions of 
 the value of the method of conditioned reflexes as a 
 means of studying young children pointed to a further 
 study of the method itself as necessary and probably 
 valuable. His work is, however, distinctly medical and 
 the terminology needed interpretation and assimilation 
 into that of our psychological studies while his method 
 needed refining and standardization. 
 
 A careful study of the terminology shows that the 
 conditioned reflex is neither more nor less than an 
 association developed between an arbitrarily de- 
 termined stimulus and some response habitually caused 
 by some other stimulus. This response may be one 
 functioning in everyday life, or as used by Bechterew, 
 is itself sometimes an artificially developed response. 
 
 Experimentation with the method verifies Krasno- 
 gorski's claims for it. It can easily be adapted to vary- 
 ing and multiform conditions. 
 
 The conditioned reflex can easily be established in 
 normal children of one year of age and in defectives 
 mentally much less. The lower age limit of its pos- 
 sible development in normals has not yet been ascer- 
 tained. 
 
 The results obtained from the use of this method 
 upon a total of 67 children are as follows: 
 
CONCLUSIONS aOl 
 
 Unselected group. 
 
 1. The learning of a conditioned reflex requires from 
 3 to 9 trials in normal children. This is a nar- 
 rower range than that found by Krasnogorski. 
 
 2. The number of trials required decreases as age 
 increases up to the age of 60 months, above this age 
 the results are less regular. 
 
 3. The number of trials required is also influenced 
 by sex. Under two years of age the boys learn more 
 rapidly than girls of the same age. Above two this 
 order is reversed. The number of trials required va- 
 ries more among the girls than with the boys. 
 
 4. With children of the same age those who learn 
 more rapidly are also brighter as measured by the re- 
 sults obtained through the use of the Binet and Yerkes 
 scales. 
 
 5. With children learning in the same number of 
 trials the older ones have higher ratings on the Binet 
 and Yerkes scales. 
 
 6. In general there is a slight tendency for the chil- 
 dren who are more rapid in learning the association to 
 be more rapid in performance of the Seguin Form 
 Board, although when we study the order of merit for 
 Form Board ability we find the most rapid learners 
 on the Krasnogorski method are medium in their abil- 
 ity there. 
 
 7. Those who are more rapid in learning are also 
 more apt to succeed upon the Adaptation Board. In 
 general the number of trials completed upon the Adap- 
 tation Board is in inverse order when compared with 
 the number of trials for learning, the distribution of 
 the boys being more regular. 
 
 8. The number of trials needed for learning de- 
 creases as the grip ability increases. This holds in 
 
20^ CHILD BEHAVIOR 
 
 lesser degree for the grip-height index and most mark- 
 edly in the grip-weight index. 
 
 9. The rate of learning increases as the spirometer 
 ability increases. This is also true of the vital in- 
 dices. 
 
 10. After a twenty-four-hour interval the condi- 
 tioned reflex functions at once in over seventy per 
 cent of the unselected group. 
 
 11. The number of trials needed for releaming va- 
 ries only from S to 7, being less than the learning 
 range. 
 
 12. This variability in retention appears independ- 
 ent of the age of the child. 
 
 13. There is a moderate relation between learning 
 ability and retention. The most rapid learners retain 
 best and their average score, which without exception 
 was one of complete retention, is equaled by only one 
 other group, the one which learned most slowly. Those 
 intermediate in learning ability are less successful in 
 retaining. 
 
 14. The range of trials required for releaming is 
 less among the girls than among the boys. 
 
 15. The mechanism of inhibition or unlearning of 
 the association was developed in 41 of the unselected 
 group. The youngest nine reacted antagonistically to 
 the situation which confronted them in the attempt to 
 develop the unlearning and hence scored failures on 
 this process. 
 
 16. The number of trials needed for developing the 
 inhibition or unlearning ranged from 3 to 12, the 
 range being greater for the boys than for the girls. 
 
 17. In general the number of trials needed for un- 
 learning the conditioned reflex decreases as age in- 
 creases. 
 
CONCLUSIONS a03 
 
 18. There are marked sex differences, more of the 
 boys developing the unlearning rapidly, more of the 
 girls requiring a greater number of trials. 
 
 19. The number of trials needed for unlearning tends 
 to decrease as the number of trials needed for learning 
 increases. This relation is more constant among the 
 boys than among the girls. 
 
 20. There is a slight indication that the number of 
 trials needed for effecting unlearning is greater the 
 fewer the number of trials needed for memorial re- 
 functioning or re-learning after a twenty-four-hour in- 
 terval. (This would be in accordance with Jost's 
 
 law.) 
 
 ai. For children of the same age the number of trials 
 needed for developing unlearning is in all but one in- 
 stance greater for the girls than for the boys. 
 
 22. For all the children developing unlearning in 
 the same number of trials the mental age by Binet in- 
 creases as the chronological age increases when sub- 
 division is made according to sex. The regularity of 
 distribution by the Yerkes age is slightly less. 
 
 23. In the children of any one chronological age, 
 grouped according to the number of trials they re- 
 quired to develop an inhibition or unlearn the condi- 
 tioned reflex, the situation is more complex. For boys 
 the mental age by Binet or Yerkes increases, up to a 
 certain point, as the number of trials required in- 
 creases, then for those requiring more trials the men- 
 tal age is less. This relation is different in children 
 of different ages. For girls the distribution indicates 
 that the duller children require more nearly the median 
 number of trials, the brighter children developing an 
 inhibition in either a lesser or a greater number of 
 trials. 
 
^04 CHILD BEHAVIOR 
 
 24. There is a slight indication that those children 
 who are more rapid in unlearning can complete the 
 Seguin Form Board with better time records than those 
 who unlearn slowly. 
 
 25. The number of turns of the Adaptation Board 
 which are successfully completed is greater among 
 those children who unlearn more rapidly. 
 
 26. There appears to be a slight positive relation 
 between the increase in average grip and the decrease 
 in number of trials necessary to develop unlearning. 
 This relation is less marked when we use the grip in- 
 dices. 
 
 27. There is practically no relation between the 
 vital indices and the number of trials necessary to ef- 
 fect inhibition or unlearning of the conditioned re- 
 flexes. 
 
 28. The relearning of or re-establishment of the 
 conditioned reflex functions without much perceptible 
 difference in children of all ages and both sexes, al- 
 though there are several individual variants. The sig- 
 nificance of these can not be established without further 
 work at this point. 
 
 Defectives. 
 
 29. The learning process in defectives is such that 
 they require anywhere from 3 to 18 trials to develop 
 a conditional reflex. 
 
 30. The number of trials needed for this learning is 
 not directly proportional to the mental ability of the 
 child but is also relative to his chronological age. 
 
 31. The range of number of trials needed to de- 
 velop a reaction after 24 hours is the same as that in 
 the unselected group, 2-7. However, instead of over 
 10% using only 2 trials we have here but 4 out of 
 7 or 51% with whom 2 trials were sufficient. 
 
CONCLUSIONS 205 
 
 32. Although only two of the defectives studied were 
 girls there is an indication that with this group as 
 well as with the unselected group there are important 
 sex differences. 
 
 33. The number of trials required for inhibition or 
 unlearning varies from 8 to 21. 
 
 34. The association or conditioned reflex is in every 
 instance relearned or redeveloped in two trials. 
 
 35. The greatest deviation of these borderline defec- 
 tives as a group from the unselected group lies in the 
 number of trials necessary for the development of un- 
 learning. Only three of the defective group effect this 
 in a number of trials which lies within the range of 
 normal performance and this overlapping is true only 
 when the two groups are treated as wholes. If we 
 place any defective girl or boy in the unselected group 
 in the place where he would belong by virtue of his 
 age, sex and mentality as measured by the Binet or 
 Yerkes scale he will be outside the range of variations 
 of the unselected group in the number of trials he 
 needs to develop unlearning. The only case in the un- 
 selected group with which any one from the defective 
 group is homogeneous in behavior in unlearning is the 
 little son of the feeble-minded man and the insane wo- 
 man. 
 
 36. In the case of children whom other tests leave 
 undiagnosed or unprognosed these methods indicate a 
 procedure which makes a more fundamental test of the 
 mental processes and consequently they discriminate 
 potential defectives and psychasthenics in a way that 
 is more highly prognostic than are the results of any 
 other test now employed. 
 
 37. The method seems even more valuable because 
 its findings upon any one child seem to indicate that 
 
CHILD BEHAVIOR 
 
 the conditioned reflex processes are influenced in the 
 rate of their functioning by sex, age, heredity ; are cor- 
 related with ability upon other tests, with measure- 
 ments like grip and lung capacity and are probably 
 influenced by glandular disturbances. As a result 
 they give us in a simple numerical form a rating which 
 facilitates our comprehension of the total endowment 
 Nature has given the child. 
 
 By no means, however, do I wish it to be thought 
 that I favor the use of the Krasnogorski processes in 
 place of other methods in clinical examination. In- 
 stead I believe that the study of the individual child 
 for the purpose of prognosis or merely for a better 
 understanding of his nature is not to be accomplished 
 by the esoteric usage of any individual method, no 
 matter how high its claims. Just as binocular vision 
 gives us a third dimension so every additional line of 
 approach to a child's mental processes allows us to 
 understand and evaluate them more fully. 
 
 No child should be diagnosed as normal or abnor- 
 mal unless he has been studied from every possible as- 
 pect. This idea has been emphasized by Fernald (44). 
 Everj'^ child must be surveyed through the eyeglasses of 
 anthropometrical measurements, heredity, his history 
 from the time of conception, his educational history, 
 present and functioning educational acquisitions, his 
 general knowledge gained from experience in his social 
 group outside school, his social, moral and economic 
 reactions as well as from the viewpoint of exact meas- 
 urement of mental processes. Of course the pre-school 
 child is too young to have much of a history in several 
 of these lines and hence it is even more important that 
 the others be accurately evaluated. I do think, how- 
 ever, that experiments such as the Krasnogorski which 
 
CONCLUSIONS 207 
 
 deal with definite neutral situations are more funda- 
 mental and as they become more numerous will tend to 
 replace the arbitrary tests of acquired knowledge. 
 
 But one thing needs to be kept in mind. The child 
 is an individual and must be treated and studied as 
 such whether he as an individual is the whole problem 
 or only one of a group forming the subject matter 
 of a problem. No success may be ascribed to studies 
 which disregard this fact. The day for the mere ab- 
 straction of one item, its cold manipulation and the 
 absolute deduction of facts therefrom is past. We 
 must realize the eternal interplay of all of the many 
 factors in the child and his environment. The more of 
 these we can grasp the nearer shall we come to the 
 explanation and understanding of any one of them. 
 This does not mean not submitting the child to arbi- 
 trary laboratory conditions for studying him. Give 
 him if you will time limits within which he must do 
 so and so or must not do so and so, but keep the con- 
 ditions constant for that problem, noting as many fac- 
 tors in the situation as you yourself are aware of. Only 
 by doing this shall we come to an understanding of 
 the whys and the wherefores which make of the child a 
 growing and functioning unity. 
 
CURVES ILLUSTRATING THE DEVELOPMENT 
 OF CONDITIONED REFLEXES 
 
 In all curves the dash in the topmost line represents 
 the moment of feeding. 
 
 The second line is the record of the throat and chin 
 movements of the child. 
 
 The bottom line is the time recorded in seconds. 
 
 Case 31. — Gertrude, aged 61 months, who tests 62 by the Binet and 
 5.0 by the Point. 
 
 Trial 1. — Child lying quiet 
 until fed. 
 
 Trial, 2. — Child not react- 
 ing before she was fed. 
 
 209 
 
210 
 
 CHILD BEHAVIOR 
 
 Trial 3. — Mouth opened 
 before feeding. 
 
 Tkial 4. — Mouth again 
 opened before the feed- 
 ing. 
 
 Case 31, after 24 hours. 
 
 Tkial 1. — Reaction 
 ing. 
 
 before feed- 
 
DEVELOPMENT OF REFLEXES 211 
 
 Trial 2. — Reaction before feed- 
 ing, child not fed but un- 
 learning begun. 
 
 Trial 3. — Reaction to bandage, no 
 feeding. 
 
 Trial 4. — Reaction to bandage, no 
 feeding. 
 
212 
 
 CHILD BEHAVIOR 
 
 Tbial 5. 
 
 -Marked and violent re- 
 action. 
 
 Trial 6. — Continued reaction. 
 
 Tbial 7. — Reaclion continued. 
 
DEVELOPMENT OF REFLEXES 213 
 
 Trial 8. — Almost quiet. 
 
 Trial 9. — Slight swallowing. 
 
 Trial 10. — Violent mouth opening and 
 swallowing. 
 
214 
 
 CHILD BEHAVIOR 
 
 Trial 11. 
 
 -No reaction throughout the 
 period. 
 
 Trial 12. — Child quiet until fed. 
 Unlearning was perfected and 
 re-learning begun. 
 
 Trial 13.— Re-learning effected. 
 Child opens her mouth before 
 time for feeding. 
 
SELECTED RECORDS FROM OTHER CASES 
 
 ILLUSTRATING VARIOUS STAGES IN THE DEVELOP- 
 MENT OF CONDITIONED REFLEXES 
 
 Case 30, Margaret, 59 months old, 
 Binet 6*. Learning was de- 
 veloped in 4 trials, and func- 
 tion was immediate after 24 
 hours. This is the reaction 
 upon the sixth trial for ef- 
 fecting unlearning. Child lay 
 tense with heavy breathing 
 and opened mouth. Two more 
 trials were needed for un- 
 learning. 
 
 Case 39, Clarence, 73 months old, 
 Binet 6^ Learning required 
 6 trials and recall after 24 
 hours was immediate. Ac- 
 companying curve shows un- 
 learning fully developed and 
 re-learning begun after only 
 4 trials. 
 
 Case 23, Jackie, 51 months old, 
 Binet 5*. Curve shows learn- 
 ing fully developed and 
 marked reaction before feed- 
 ing on this, the third trial. 
 In this case unlearning re- 
 quired 9 trials. 
 
 215 
 
216 
 
 CHILD BEHAVIOR 
 
 Case 24, Marie, 51 months old, 
 Binet 5^. Learning required 
 5 trials, recall was immediate 
 but unlearning took 10 trials. 
 Re-learning was then begun. 
 This curve shows the third 
 trial for re-learning which 
 evidenced itself on the fourth 
 trial. No reaction before 
 feeding. 
 
 Case 19, Russell, 48 months old, 
 Binet 5^. Learning complete 
 on this the fifth trial. Re- 
 call after 24 hours required 3 
 trials and unlearning 7 but 
 re-learning only 2 trials. 
 
 Case 12, James, 36 months old, 
 Binet 3*. After forming the 
 association in 7 trials he re- 
 calls in 2 trials and then 
 takes 12 trials to unlearn. 
 The curves show the ninth 
 and eleventh trials in the de- 
 velopment of unlearning. 
 
DEVELOPMENT OF REFLEXES 217 
 
 Case 12, Ray. 34 months 
 old, Binet 4i. Learn- 
 ing took 6 trials and 
 recall 3 trials while 
 unlearning took 6 
 trials. The sixth trial 
 for unlearning and the 
 first feeding for re- 
 learning are shown 
 in this curve. 
 
 Case 25, Alice, 51 months 
 old, Binet 4^. Learn- 
 ing took 3 trials and 
 recall was immediate 
 after 24 hours. Un- 
 learning took 8 and 
 re-learning 2 trials. 
 The curve shows the 
 fourth trial at unlearn- 
 ing, given after she 
 had said, "Give me 
 a piece of candy this 
 time." "Psychic stim- 
 ulation" is surely at 
 work. 
 
 Case G, Esther, 81 months 
 old, Binet 6\ She de- 
 veloped the association 
 in 13 trials. Its ap- 
 pearance is shown in 
 curves for the eleventh 
 and twelfth trials re- 
 produced here. She 
 took 7 trials for the 
 24 hour recall, 8 to 
 unlearn and 2 to re- 
 learu. 
 
gl8 
 
 CHILD BEHAVIOR 
 
 Case P, Crahil, 93 months 
 old, Binet 72. He 
 learned in 5 trials and 
 recalled in 2 but took 
 14 to unlearn. Curves 
 12 and 13 are pre- 
 sented here and show 
 the disappearance of 
 the reaction. He re- 
 learned in 2 trials. 
 
 Henry, 75 months old, 
 Binet 62. This is the 
 boy who could not get 
 along in school but 
 who by other tests is 
 apparently normal. 
 The curves show the 
 nineteenth and twenty- 
 first trials given in an 
 attempt to have him 
 unlearn the reaction 
 learned in 7 trials. 
 He reacts in the nine- 
 teenth but has by the 
 twenty-first been quiet 
 twice successively and 
 re-learning is begun. 
 
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INDEX 
 
 Activity, as reflex, 66 ; potential- 
 ity for, 70. 
 
 Adaptation, 71, 102. 
 
 Adaptation board, 111, 142, 171- 
 173, 179, 204. 
 
 Affective values, 194. 
 
 Ahil, 119-120. 
 
 "Analysers," 80-82, 89. 
 
 Anencephalic child, 92. 
 
 Anthropometric measurements, 
 
 111, 142-143, 174-180. 
 Apparatus, 27, 75-76, 102 ; child's 
 
 adjustment to, 107. 
 
 Artificial stimulus, 64, 77 ; see 
 also conditioned stimulus. 
 
 Association, 67, 90, 92 ; condi- 
 tioned, 140 ; formation of, 45, 
 59, 147 ; verbal, 92 ; see also 
 learning. 
 
 Attitude of child, 96, 100, 109, 
 186. 
 
 Attitude towards child, Christian, 
 13, 196 ; genetic, 19, 197 ; 
 Greek, 13 ; pedagogical, 16, 17, 
 46, 196 ; psychological, 49, 51, 
 198-199; religious, 17, 18, 196. 
 
 Aufgabe, 195 ; use of, 58, 60, 195 ; 
 verbal, 51, 58, 109, 147. 
 
 Aussage tests, 44, 
 
 Aussagen, 128, 129, 187-188, 
 194. 
 
 Autobiographies, 18, 39. 
 
 Baldwin, 28, 37, 72. 
 Bechterew, 65-66, 69, 199-200. 
 Behavior, aim of, 55 ; study of, 
 
 33, 52, 53fle. 
 Bickel, 68, 72, 
 Binet, 41, 43, 44, 110, 128, 141, 
 
 161-168, 169, 178, 179, 201, 
 
 203, 205. 
 Biographies of children, 18, 21, 
 
 22, 25, 28, 30, 33, 39. 
 Bogen, 68-69, 72. 
 Borderline cases, 112, 180-183. 
 
 Child an organism, 70-71, 199. 
 Child behavior defined, 7. 
 Child behavior problems, 8. 
 Children, entering school, 19, 20, 
 28, 47; "not feeble-minded," 
 
 112, 164, 183-185 ; under 1 year 
 old, 191 ; unselected group, 48, 
 95, 103fle, 137fiE. 
 
 Child's Congress, 31. 
 
 Child study, 56, 196 ; America, 
 28, 29, 30; anthropological, 23, 
 30 ; autobiographies, 18, 39 ; 
 Belgium, 24 ; biographical, 18, 
 21, 22, 25, 28, 30, 33, 39 ; clas- 
 sification, 32-33 ; color discrim- 
 ination, 22, 23, 25, 27, 36, 37, 
 87, 198; Denmark, 30; diffi- 
 culties with younger children, 
 48-49 ; England, 26-27 ; factors 
 influencing, 42 ; first record, 
 15 ; founder, 16 ; France, 24- 
 25, 30 ; genetic, 36, 197 ; Ger- 
 many, 22-24, 30; history of, 
 23, 25 ; language, 19, 21, 23, 
 2^, 28, 32, 36-37, 45-47, 197; 
 physio - psychological, 19-21, 
 32 ; Poland, 30 ; Portugal, 31 ; 
 results of, 32ff ; Russia, 26 ; 
 social customs, 23 ; specializa- 
 tion in, 30 ; theory of, 70-71, 
 199 ; use of term, 6. 
 
 Chronological ago, 140, 146-147, 
 148-153, 165-166, 167, 201, 
 202, 203, 
 
 Classification of child study, 32- 
 33. 
 
 Clinical procedure, 189 ; value, 
 86, 93, 189, 205-206. 
 
 Color discrimination, 22, 23, 25, 
 27, 36, 37, 87, 198. 
 
 Comenius, 14. 
 
 Conditioned reflexes, 64-67, 73- 
 
 93, 94, 200ff; "analysers." 80- 
 82, 89; apparatus, 75-76, 94, 
 95, 102 ; applicability, 194-195 ; 
 characteristics or, 64 ; condi- 
 tioned centers, 82 ; conditioned 
 inhibitions, 83, 91, 100 ; condi- 
 tioned stimulus, 75, 97 ; devel- 
 opment of, 64, 79ff, 92, 115- 
 127, 128 ; developmental stages, 
 82, 126-127, 130ff, 209-218 ; dis- 
 crimination of stimuli, 124, 126- 
 127, 131, 133, 134 ; formation 
 of, 64, 68-69, 75, 79, S2ff, 95fl, 
 148 ; in defectives, 79, 81, 82, 
 
 94, 103, 112, 113-127, 204-205, 
 217-218 ; learning of. 68, 76, 85, 
 90, 140, 147-152, 153, 154, 156- 
 159, 164-168, 169. 172, 178, 
 192, 201-202, 204, 209-210, 
 215, 216; loading and dis- 
 
 237 
 
INDEX 
 
 charge," 83-85 ; mechanisms, 
 79, 83, 85-86, 91, 127; me- 
 morial conditioning, 84, 90, 
 134 ; memorial effect of stimu- 
 lus, 78, 89 ; memorial function- 
 ing of, 76ff, 99, 102, 116-118, 
 120, 122, 123, 135, 140-141, 
 152-154, 202 ; method, 63, 65, 
 73, 76, 86-87, 97; pathological 
 differentiation, 79-84 ; see also 
 clinical value ; principle of, 
 89-92, 193-194; re-agents, 76, 
 94, 95, 104, 112 ; relearning of, 
 
 101, 102, 141, 160-161, 202- 
 203, 205, 214-217; renewal, 
 77ff ; see also relearning ; re- 
 sults obtained by Krasnogorski, 
 76-83, 89, 147, 148, 156, 191, 
 199-200 ; retention of, 102, 128, 
 134, 152-154, 202, 210-211; 
 specificity of, 77, 80, 82, 129, 
 130, 131, 132, 133; stimulus, 
 natural, 64, 114 ; stimulus, 
 used, 74, 76, 114 ; time inter- 
 val, 87-88, 97-98, 99; uncondi- 
 tioned stimulus, 64, 75, 114 ; 
 unlearning, 77ff, 85, 90, 100, 
 
 102, 133, 141, 154-159, 166- 
 167, 172, 178, 202, 203-204, 
 205, 211-214, 215, 216, 217, 
 218 
 
 Conditioned stimulus, 64, 75, 97; 
 
 modification of, 114. 
 Correlation coefiicients. 143-146. 
 Correlative study, 6, 7, 190. 
 Curves, evaluation, 189-190, 209- 
 
 218, 
 
 Defectives, 79, 81, 82, 85, 94, 96, 
 112, 113-127, 180-195, 204-205, 
 217, 218; borderline, 112; 
 learning of, 85, 180-182, 204; 
 study of, 96, 103, 113-127, 180- 
 183, 204-205 ; unlearning, 85, 
 182-183, 205. 
 
 Delayed reactions, 58-59. 
 
 Diaries, child study, 33. 
 
 Digestive glands, 62-65. 
 
 Discussion, 185ff, 
 
 Drawings of children, 47-48, 
 
 Dynamometer findings ; see psy- 
 chomotor measurements. 
 
 Emotional attitude, 186, 
 Experimental studies, 51, 56-60. 
 Experiments, place of, 34, 35, 
 36, 37-38, 42, 49-51, 
 
 Fatigue, 89, 98, 186. 
 Forgetting, 102 ; see also reten- 
 tion. 
 
 Games, 47. 
 
 Garbini, 25. 
 
 George, 125-127. 
 
 Goddard, 110, 111, 146, 171. 
 
 Grip ; see psychomotor measure- 
 ments. 
 Growth as a factor, 70-71, 199. 
 
 Habit, 54-55, 70, 90, 92. 
 
 Hall, 28, 29, 40, 46. 
 
 Hamilton, 56, 60, 
 
 Handling children, 102-108, 185- 
 186, 
 
 Healy boards, 110, 173. 
 
 Height ; see anthropometric meas- 
 urements. 
 
 Hunter, 58-60. 
 
 Idiots, 79, 81, 82, 94, 103, 113- 
 
 127, 
 Individual, studies of, 18, 21, 22, 
 
 25, 28, 30, 33, 39, 
 Instinct, 54-55, 70. 
 Intelligence tests, 30, 41, 86. 
 Interest, 185, 
 Interrelation of studies, 33. 
 
 Jock, 123-125. 
 John, 122-123, 
 Jorsi, 120-122. 
 
 Katz, 50, 51, 60. 
 
 Krasnogorski, 72, 73-86, 96-97, 
 
 147, 148, 156, 191, 199-200; 
 
 criticism of, 86-93. 
 
 Language, 19, 21, 23, 25, 28, 32, 
 36-37, 45-47, 197 ; quantitative 
 studies of, 37. 
 
 L'Annee Psychologique, 24. 
 
 Learning, 51, 68, 71, 76, 85, 90, 
 140, 147-152, 153, 154, 156- 
 159, 164-168, 169, 172, 178, 
 192, 201-202, 204, 209-210, 215, 
 216, 217. 
 
 Learning in defectives, 113-127. 
 
 Learning process, 47, 68, 195, 
 
 Leitba, 115-118. 
 
 "Loading and discharge," 83-85. 
 
 Lombroso, Paola, 25. 
 
 Lung capacity ; see psychomotor 
 measurements. 
 
 Machado, 31. 
 
 Maze, 58. 
 
 Memory, 47, 67, 102, 141 ; stud- 
 ies of, 43-45, 51 ; see also con- 
 ditioned reflexes. 
 
 Methods, Aussage, 44 ; autobiog- 
 raphy, 38-39 ; behavior, see ex- 
 perimental ; dynamogenic, 37, 
 38 ; experimental, 34, 35, 36, 
 37-38, 42, 49-52, 197 ; exten- 
 sive, 19; first, 33; multiple 
 choice, 57 ; objective, 91, 198 ; 
 physiological, 23, 25, 42-43, 
 196 ; psycho-analysis, 39 ; quad- 
 ruple choice, 56 ; quantitative, 
 40-41 ; questionnaire, 39-40 ; 
 retrospection, 45, 
 
 Meumann, 36, 47. 
 
INDEX 
 
 239 
 
 Motive in child study, evolution, 
 49 ; pedagogy, 48 ; see also at- 
 titude. 
 
 Motor development, 43, 198. 
 
 Motor reflex, 66, 81 ; response, 37, 
 73. 
 
 Neuro-psychopaths, 79-80, 81, 82, 
 
 83, 85, 136. 
 Number of cases, 188. 
 
 Objective methods, 91, 198. 
 Organism, 5, 54, 91 ; child an, 
 70-71, 199. 
 
 Partil, 103, 127-134, 135, 136. 
 
 Pasha, 118. 
 
 Pavlov, 60, 62-65, 69, 199. 
 
 Pedagogical Seminary, 29. 
 
 Perez, 21, 28, 34. 
 
 Pestalozzi, 15, 16, 34. 
 
 Play, 99, 103, 195. 
 
 Pohlmann, 46-47. 
 
 Point Scale, 110, 128, 142, 161- 
 168, 169, 179, 201, 203, 205. 
 
 Pre-school age, 6, 32, 48, 206. 
 
 Preyer, 22, 28, 34, 43, 192. 
 
 "Psychic excitation," 64. 
 
 Psychology, and biology, 53 ; 
 child, 5, 33, 50; defined as be- 
 havior, 54ff ; divisions of, 5 ; 
 educational, 5-6 ; of adoles- 
 cence, 6 ; of child, defined, 6. 
 
 Psychomotor findings, 174-180, 
 201-204. 
 
 Psychomotor measurements, 112, 
 143. 
 
 Punishment motivation, 67. 
 
 Quantitative studies, 40. 
 
 Reassociation, 102 ; see also re- 
 learning. 
 
 Reflex as a unit, 54-55. 
 
 Reflex, cerebral, 60-62, 89. 
 
 Reflex, motor, 66, 81. 
 
 Reflexes : see conditioned re- 
 flexes. 
 
 Eelearning, 101, 102, 141, 160- 
 161, 202-203, 205, 214-216, 217. 
 
 Results, genetic, 42. 
 
 Retention, 102, 128, 140-141, 152- 
 154, 202. 210-211 ; in defec- 
 tives, 113-127. 
 
 Reward motivation, 60, 67. 
 
 Rousseau, 14-15. 
 
 Schleiermacher, 17, 196. 
 School entrance studies, 20. 
 Seguin form board. 111, 142, 168- 
 
 171, 179, 201, 204. 
 Setchenov, 60-62. 
 Sex differences, 47, 151-152, 154- 
 
 159, 162, 177, 188-189, 203- 
 
 204, 205. 
 Shinn, 28, 34, 43. 192. 
 Sikorskii, 26. 
 Stern. 23, 34-36, 44, 192. 
 Stimulus, 57, 60, 64, 70, 71, 76flE, 
 
 79, 89, 96 ; appeal of, 58, 194 ; 
 
 modification of, 114. 
 Successful work, 185. 
 Sully, 26. 
 Synthetic study, 190, 206. 
 
 Tests of intelligence, 30, 41, 86. 
 Tests, supplementary, 108, 110- 
 
 112. 
 Tiedemann, 16, 42. 
 Time interval, 87-88, 97-98, 99. 
 
 Unlearning, 77£E, 85, 90, 100, 102, 
 133, 141, 154-159, 166-167, 172, 
 178, 202, 203-204, 205, 211- 
 214, 215, 216, 217, 218. 
 
 Unselected group, 48, 95, 103ff, 
 137, 201-204. 
 
 Vital index, 178-180 ; see psy- 
 chomotor measurements. 
 
 Warner, 26-27, 72. 
 Watson, 54-56, 66-68, 199. 
 Weight ; see anthropometric meas- 
 urements. 
 
 Yerkes, 56, 57-58, 60, 161-168, 
 201.