key: cord-0734447-9bpinpfg
authors: Dezecache, Guillaume; Frith, Chris D.; Deroy, Ophelia
title: Pandemics and the great evolutionary mismatch
date: 2020-05-18
journal: Curr Biol
DOI: 10.1016/j.cub.2020.04.010
sha: dd3888c8211b8b208bd92c0b066345a2e8c56c27
doc_id: 734447
cord_uid: 9bpinpfg

Dezecache et al. argue that affiliation and contact-seeking are key responses to danger. These natural social tendencies are likely to hinder the observance of physical distancing during the current pandemic. We need internet access at this time, not only to promote freedom of expression, but also to promote public health.

What do humans do when faced with a collective threat? This is a core question for psychology and is of major practical concern for the covid-19 pandemic. But do we have anything useful to share with governments and the media, or is this just an attempt to persuade ourselves that we can make some contribution when we feel powerless in front of the spread of this virus?

We could simply retire to the 'safety' of our ivory towers and leave everyone else to worry, but the fact that we have a strong drive to do something tells a very different story from the one that still dominates the social and psychological sciences and the media. This is the idea that danger brings out the worst in us: panic, antisocial behaviour, and fi erce competition for material and physical resources (see [1] for a review). Moral transgression and the abandonment of social norms may sometimes occur and certainly colour public imagination, but this behaviour tends to be rare. Sociological and psychological studies show that, under stress, people frequently remain calm and cooperative [1, 2] . What's more, rather than selfi sh avoidance, it is cooperation and contact-seeking that are our primary responses to threat [1] [2] [3] [4] [5] [6] .

What increases in times of anxiety and threat is not a drive to help the self at all costs, but an intuitive drive to help others. The unfortunate consequence is that, in response to the current threat of infection, we desire social contact, particularly with the loved and the vulnerable.

When describing the behaviour of people living in countries affected by the spread of covid-19, the media has rapidly adopted a 'Hobbesian' view of human nature [4] . This is the expectation that exposure to threat makes people abandon social niceties and, being naturally rivals, fall back into 'brutishness and misery'. Major newspapers report panic, with people running to shops to collect masks, hand sanitizers and food. Those behaviours are routinely qualifi ed as irrational: why rush to buy food when we are told that there will be no shortages? We do not doubt that humans can be irrational (we misevaluate large magnitudes; underestimate risks and value shortterm gain [7] ). At the individual level, however, it is rational to hoard food and toilet paper when we are told that we will have to stay at home for an indefi nite amount of time. It's not that we do not trust politicians, but we are right to be uncertain about the resilience of institutions, and the social contract in general, in the face of an unprecedented, unknown, and growing threat. Similarly, it is perfectly rational, at the individual level, to run for the exits when the building is on fi re. However, these self-oriented rational decisions are the ones on which we have to consciously refl ect [8] . Our initial, intuitive responses are, on the contrary, to be cooperative [9] .

In real-life threatening circumstances, people do not take time and coldly deliberate about what behaviour would most suit their self-interest -leave others behind, and (metaphorically) run to the exit with suffi cient food (and toilet paper). On the contrary, people seek social contact. They check on each other, and even respect or re-invent social norms, with moral or altruistic content [1, 2] . We have looked at how people behaved in a theatre under terrorist attack. Where we might have expected generalised panic and stampede, we found that people formed queues to climb out to an emergency exit, while some even had voting sessions to collectively decide how best to keep safe.

The coming of covid-19 is being met with inertia and placidity, rather than mass panic. The French population was (and is still being) criticized by their own authorities for their laxity and nonchalance. Some weeks ago, the French continued to gather in bar terraces and break the obvious rules of social distancing. The German state of Bavaria took stricter confi nement measures on March 21 st , after fi nding that many individuals, despite the explicit instruction to stay away from others, were still gathering in groups as if nothing had changed. Similar violations of offi cial advice are occurring everywhere.

An alternative to the accusation that people are irrational and irresponsible is the suggestion that people are ignorant of the threat. We are not suggesting that these effects are not in play (more below), but we want to suggest that knowing the threat is perfectly compatible with seeking company of friends and loved ones. Being with others and getting but also providing social support is how we cope with stress [10] . Increasing threat is only likely to reinforce this social inclination.

Affi liation and contact-seeking as core responses to perceived danger Affi liation and physical contact-seeking are core responses to danger [4, 11] . Even in the absence of threat, spatial distancing is unnatural. In normal circumstances, a distance of around one meter is expected when interacting with friends and acquaintances [12] . Humans, like other primates, stay close to signifi cant others to create and maintain social bonds [13, 14] . Contactseeking may be a 'natural' drive which is embedded in our physiology. Social touch contributes to the physiological regulation of the body's responses to acute stressors and other short-term challenges. Close social support is not an extra for getting additional rewards. It constitutes our baseline [15] . Our brains do not respond positively to its presence, but negatively to its loss. People can crave for social cues just like they crave for food [16] . The policy Pandemics and the great evolutionary mismatch Guillaume Dezecache 1, *, Chris D. Frith 2,3 , and Ophelia Deroy 2,4,5,6

The current covid-19 crisis is reopening some of the core questioning of psychology: how do humans behave in response to threat? Can they be urged to behave differently? Panic and selfi sh behaviour are usually thought to be the prevalent responses to perceived danger. However, people affi liate and seek social contact even more when exposed to a threat. These inclinations might have been adaptive in our evolutionary past: they are our most serious problem now.

R418 Current Biology 30, R417-R429, May 18, 2020 recognized as a collective threat. Hence, the defensive avoidance mechanisms associated with fear and disgust will not operate. Similarly, our social tendencies simply continue as, in the absence of symptoms, we don't perceive that we may carry the infection. Even if we believe that the threat is widespread within our own group, the implications for oneself are challenging. Recognizing that one is likely to become a deadly threat to others is incongruent with our self-image, leading to dissonance and denial of the danger.

There is, however, a second issue: a threat stemming from infection, in societies with optimally functioning health systems, may be detected and yet recognized to be severe only for a small fraction of the population. Unless we feel we belong to that fraction, the threat may not be construed as collective: it is them, not us. A threat that remains invisible, and is thought to apply only to some individuals, is unlike other threats (such as predators, enemies or hurricanes) which are clearly menacing everyone in a given location. More than physical proximity and covulnerability is needed for a threat to be recognised as collective. Some actual or potential understanding of aspects of the threat as shared by us all, in a collective 'we' [2, 19] , is also required.

Once anchored in the idea that it affects a small fraction of people, either different from or the same as us, people are likely to miss what exponential growth means. Like the King in the legend, a cognitive limitation makes us miss that placing two grains of rice on a chessboard and multiplying them by their own number square after square will ultimately ruin us, because it will ruin everyone [20] .

What's more, populations in which people think of themselves as 'independent persons' could be more likely to downplay the severity of the problem, because they will have greater trouble imagining the threat would actually become dangerous to their loved ones, or affect society as a whole. In societies and populations where a 'conjoint' model of the self is prevalent [21] -people think of themselves as 'member of a group' and as socially interdependent -this could be the other way around: such populations may be likely to promote the emergence of collective norms and stick to them. Unfortunately, in many countries at least -and despite past pandemics such as the Spanish Flu In all likelihood, the mismatch between our misperception of the severity of the threat and its consequences is likely to become even more destructive in dense urban areas in which social isolation is a costly good.

Pathogens and viruses are old evolutionary problems: many organisms avoid contaminants and infected individuals, and infected individuals may also seek isolation, stopping the propagation of the virus. We humans also are equipped with mechanisms (for example, the feeling of disgust) to avoid possible contaminants and prevent us from being infected [22, 23] . Many studies, from sensory to more abstract cases of disgust, suggest that this mechanism is very conservative. One instance of food poisoning generates long-lasting aversive responses to the same food, as well as similar ones [24, 25] . Even knowing that the shirt worn by a sex-offender has been washed multiple times, or that a cockroach plunged in a glass in a perfectly sterile way, will suffi ce to make us refuse to use or consume these goods [26] . So why don't we avoid each other in times of infections? It is because our infection-avoidance mechanisms are overwhelmed by a much stronger drive to affi liate and seek close contact.

As a growing number of countries enforce or recommend confi nement in response to the spread of covid-19, we believe it is important to refl ect on the particular challenges these recommendations can lead to, and solutions to address them. Pace Hobbes, our great evolutionary equipment is not working to turn us away or against each other in times of peril. During collective threats, we seek even more physical closeness. These intuitive social inclinations make us implications of decades of research in social neuroscience are clear, but widely ignored: asking people to renounce social contact is not just asking them to abstain from pleasurable activities; it is asking them to diverge from a point of equilibrium, toward which they normally all gravitate.

In threatening contexts, our affi liative tendencies and desire to seek physical contact become even stronger. Rather than 'falling back' into selfi sh isolation, as in the Hobbesian picture, people who feel afraid, stressed, and threatened will not just seek social contact: they seek even more social contact [4, 11] . Research on disasters has shown that contact-seeking rather than distancing is the primary response to perceived danger, even if the latter is safer [3] . When we know there is something to lose, rather than to win, we are more prone to join others, both to diffuse stress and to reduce our feelings of responsibility [6] . Affi liative tendencies and contact-seeking would preferentially target individuals who are already familiar [3] . In their absence, people look for familiar places associated with close ones [3] . It is this, perhaps, that explains mass movements before confi nement rules are proclaimed. It is also possible that ad hoc groups emerge from scratch when threat arises, emerging from a feeling of 'common fate' [2] . Exodus away from dense city centers has occurred in several countries and has been criticized for its potentially disastrous epidemiological consequences.

That there is a threat does not mean it will be perceived as such. The same goes for its severity, or the extent to which it will be reacted to. People may give credibility to sources other than offi cial ones, and underestimate the threat, but they are not gullible [17, 18] , and danger is likely to make them even more vigilant. Many of us clearly by now believe there's a threat, but do not perceive it as a collective threat that directly affects 'us'.

One major issue is that diseases are largely invisible, particularly diseases (like covid-19) which remain asymptomatic in a large part of the population. This imperceptibility means that it is not even detected, let alone Current Biology 30, R417-R429, May 18, 2020 © 2020 Elsevier Inc. R419

hear various measures of prevention as all the same, or blur their differences: self-isolation, quarantine, lockdowns and distancing may indiscriminately trigger feelings of social loss, when they could highlight future social benefi ts.

Our social cravings, actual or anticipated, can have deadly consequences, but there is also an increasingly optimistic aspect of the story. There is growing evidence that the collective menace makes us more socially supportive and cooperative, but now we can reach out -virtually, but no less meaningfully -to neighbours, distant relatives, or even anonymous and purely potential benefi ciaries on social media. Politically, this means that access to the internet and communication is a priority, especially when the most vulnerable coincide with the less technologically connected. What will be the effects of this longterm switch to the internet? We are in the midst of a massive 'real life experiment' exploring whether our brains, and bodies, can do without physical proximity (see [27] for a preliminary answer). What we get out of this special situation matters as much as how, and how long, we can cope with it.

Hell has frozen over. The world is in the grip of a pandemic that has closed down society, shuttered your lab, and threatens to cause millions of deaths and untold economic misery. You're confi ned to your apartment, labs that have been converted into testing sites have all the volunteers they need, alcohol supplies have dwindled, and you're discovering just how desperately you love experimental science. If someone lined up every complaint you'd ever made about boring techniques, failed experiments, and your idiot advisor and wrote each one on a large, separate piece of paper, you'd happily eat them all if it would let you back into the lab to do your now beloved experiments and get on with your quest for scientifi c knowledge.

But even this extreme feat of mastication won't let you back into the lab, so what should you do? Learn Python, write a fellowship proposal, read all those papers that you've always been meaning to digest? These are good ideas, but I claim to have a better one, which is to become a better experimentalist from the comfort of your very own couch, plus everyone's favorite new medium, Zoom.

To illustrate, I'm going to call on an English Patient. I was an undergraduate in England and the department that gave my degree had coffee in the morning and tea in the afternoon. At coffee the conversation would run like this: "I have a great idea for an experiment to do this afternoon"; my friend Charlotte "Oh Andrew! I can see three missing controls, four reasons the experiment might fail, and even if it works, it's unclear that any knowledge you gain from success will be worth your time and energy." Later, at tea, I would present a revised plan with the controls added and a simplifi ed and likelier-to-succeed overall plan, but Charlotte would reply "Well that is an improvement, but I've been thinking too: I see two more missing controls and several more fl aws that make your estimates of success wildly too high."

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