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The experiment that proves it goes like this. Babies see a hand puppet trying to lift the top off a box in order to pull out a toy. Then a helpful puppet shows up and helps it open the lid and get the toy. But in another scene an anti-social puppet jumps maliciously on to the box, slamming it shut and keeping the first puppet from getting at the toy. When choosing between the two puppets, the babies prefer the helper. But here Wynn was going for something much more interesting: identifying what the babies think about stealing from an evildoer, long before they know those words.
To do this she designed a third act for the puppet theatre, and the helper puppet now loses a ball. In some cases, in this garden of forking paths, a new character appears on the scene and returns the ball. At other times, another character comes in, steals it and runs away. The babies prefer the character that returns the ball.
But the most interesting and mysterious part happens when these scenes feature the antisocial puppet that jumped maliciously on the box. In this case, the babies change their preference. They sympathize with the one who steals the ball and runs away. For nine-month-olds, the one who gives the bad guy his comeuppance is more lovable than the one who helps him, at least in that world of puppets, boxes and balls.
Preverbal babies, still unable to coordinate their hands in order to grab an object, do something much more sophisticated than judging others by their actions. They take into account the contexts and the history, which turns out to give them a pretty sophisticated notion of justice. That’s how incredibly disproportionate cognitive faculties are during the early development of a human being.
The colour of a jersey, strawberry or chocolate (#ulink_2567b044-7863-5571-8196-44e89d51bc2e)
We adults are not unbiased when we judge others. Not only do we keep in mind their previous history and the context of their actions (which we should), but we also have very different opinions of the person committing the actions, or being the victim of them, if they look like us or not (which we shouldn’t).
Throughout all cultures, we tend to form more friendships and have more empathy with those who look like us. On the other hand, we usually judge more harshly and show more indifference to the suffering of those who are different. History is filled with instances in which human groups have massively supported or, in the best-case scenario, rejected violence directed at individuals who were not like them.
This even manifests itself in formal justice proceedings. Some judges serve sentences displaying a racial bias, most probably without being aware that race is influencing their judgement. In the United States, African American males have been incarcerated at about six times the rate of white males. Is this difference in the incarceration rate a result (at least in part) of the judges having different sentencing practices? This seemingly simple and direct question turns out to be hard to answer because it is difficult to separate this psychological factor from possible racial differences in case characteristics. To overcome this problem Sendhil Mullainathan, Professor of Economics at Harvard University, found an ingenious solution, exploiting the fact that in the United States cases are randomly assigned to judges. Hence, on average, the type of case and the nature of defendants are the same for all judges. A racial difference in sentencing could potentially be explained by case characteristics or by a difference in the quality of the assigned attorneys (which is not random). But if this were all, then this difference should be the same for all judges. Instead, Mullainathan found a huge disparity – of almost 20 per cent – between judges in the racial gap in sentencing. While this may be the most convincing demonstration that race matters in the courtroom, the method is partly limited since it cannot tell whether the variability between judges’ results is due to some of them discriminating against African Americans, or some judges discriminating against whites, or a mixture of both.
Physical appearance also affects whether someone is likely to be hired in a job interview. Since the early seventies, several studies have shown that attractive applicants are typically judged to have a more appropriate personality for a job, and to perform better than their less attractive counterparts. Of course, this was not just a matter of comment. Applicants who were judged to be more attractive were also more likely to be hired. As we will see in Chapter 5, we all tend to make retrospective explanations that serve to justify our choices. Hence the most likely timeline for this line of argument is like this: first the interviewer decides to hire the applicant (among other things based on his or her beauty) and only then generates ad hoc a long list of attributes (he or she was more capable, more suited for the job, more reliable …) that serve to justify the choice which indeed had nothing to do with these considerations.
The similarities that generate these predispositions can be based on physical appearance, but also on religious, cultural, ethnic, political or even sports-related questions. This last example, because it is presumed to be more harmless – although, as we know, even sporting differences can have dramatic consequences – is easier to assimilate and recognize. Someone forms part of a consortium, a club, a country, a continent. That person suffers and celebrates collectively with that consortium. Pleasure and pain are synchronized between thousands of people whose only similarity is belonging to a tribe (sharing a jersey, a neighbourhood or a history) that unites them. But there is something more: pleasure at the suffering of other tribes. Brazil celebrates Argentina’s defeats, and Argentina celebrates Brazil’s. A fan of Liverpool cheers for the goal scored against Manchester United. When rooting for our favourite sports teams, we often feel less inhibited about expressing Schadenfreude, our pleasure at the suffering of those unlike us.
What are the origins of this? One possibility is that it has ancestral evolutionary roots, that the drive collectively to defend what belonged to one’s tribe was advantageous at some point in human history and, as a result, adaptive. This is merely conjecture but it has a precise, observable footprint that can be traced. If Schadenfreude is a constituent aspect of our brains (the product of a slow learning process within evolutionary history), it should manifest itself early in our lives, long before we establish our political, sports or religious affiliations. And that is exactly how it happens.
Wynn performed an experiment to ask whether infants prefer those who help or harm dissimilar persons. This experiment was also carried out in a puppet theatre. Before entering the theatre, a baby between nine and fourteen months old, seated comfortably on their mother’s lap, chose between crackers or green beans. Apparently, food choices reveal tendencies and strong allegiances.
Then two puppets came in, successively and with a considerable amount of time between the two entrances. One puppet demonstrates an affinity with the baby and says that it loves the food the child has chosen. Then they leave and, just as before, there is another scene where the puppet with similar taste is playing with a ball, drops it and has to deal with two different puppets: one who helps and the other who steals the ball. Then babies are asked to pick up one of the two puppets and they show a clear preference for the helper. One who helps someone similar to us is good. But when the puppet who loses the ball is the one who had chosen the other food, the babies more often choose the ball robber. As with the thief, it is gastronomic Schadenfreude: the babies sympathize with the puppet that hassles the one with different taste preferences.
Moral predispositions leave robust, and sometimes unexpected, traces. The human tendency to divide the social world into groups, to prefer our own group and go against others, is inherited, in part, from predispositions that are expressed very early in life. One example that has been particularly well studied is language and accent. Young children look more at a person who has a similar accent and speaks their mother tongue (another reason to advocate bilingualism). Over time, this bias in our gazes disappears but it transforms into other manifestations. At two years old, children are more predisposed to accept toys from those who speak their native language. Later, at school age, this effect becomes more explicit in the friends they choose. As adults, we are already familiar with the cultural, emotional, social and political segregations that emerge simply based on speaking different languages in neighbouring regions. But this is not only an aspect of language. In general, throughout their development, children choose to relate to the same type of individuals they would have preferentially directed their gaze at in early childhood.
As happens with language, these predispositions develop, transform and reconfigure with experience. Of course, there is nothing within us that is exclusively innate; to a certain extent, everything takes shape on the basis of our cultural and social experience. This book’s premise is that revealing and understanding these predispositions can be a tool for changing them.
Émile and Minerva’s owl (#ulink_a27d08aa-47a0-5160-96f3-a2b020aa2df4)
In Émile, or Concerning Education, Jean-Jacques Rousseau sketches out how an ideal citizen should be educated. The education of Émile would today be considered somewhat exotic. During his entire childhood there is no talk of morality, civic values, politics or religion. He never hears the arguments we parents of today so often go on about, like how we have to share, be considerate of others, among so many other outlines of arguments for fairness. No. Émile’s education is far more similar to the one Mr Miyagi gives Daniel LaRusso in The Karate Kid, pure praxis and no words.
So, through experience, Émile learns the notion of property at twelve years old, at the height of his enthusiasm for his vegetable garden. One day he shows up with watering-pot in hand and finds his garden plot destroyed.
But oh, what a sight! What a misfortune! [ … ] What has become of my labour, the sweet reward of all my care and toil? Who has robbed me of my own? Who has taken my beans away from me? The little heart swells with the bitterness of its first feeling of injustice.
Émile’s tutor, who destroyed his garden on purpose, conspires with the gardener, asking him to take responsibility for the damage and gives him a reason to justify it. Thus the gardener accuses Émile of having ruined the melons that he’d planted earlier in the same plot. Émile finds himself embroiled in a conflict between two legal principles: his conviction that the beans belong to him because he toiled to produce them and the gardener’s prior right as legitimate owner of the land.
The tutor never explains these ideas to Émile, but Rousseau maintains that this is the best possible introduction to the concept of ownership and responsibility. As Émile meditates on this painful situation of loss and the discovery of the consequences of his actions on others, he understands the need for mutual respect in order to avoid conflicts like the one has just suffered. Only after having lived through this experience is he prepared to reflect on contracts and exchanges.
The story of Émile has a clear moral: not to saturate our children with words that have no meaning for them. First they have to learn what they mean through concrete experience. Despite this being a recurrent intuition in human thought, repeated in various landmark texts of the history of philosophy and education,
today hardly anyone follows that recommendation. In fact, almost all parents express an endless enumeration of principles through discourse that we contradict with our actions, such as on the use of telephones, what we should eat, what we should share, how we should say thank you, sorry and please, not be insulting, etc.
I have the impression that the entire human condition can be expressed with a piñata. If a Martian arrived and saw the highly complex situation that suddenly arises when the papier mâché breaks and the rain of sweets falls out, it would understand all of our yearnings, vices, compulsions and repressions. Our euphoria and our melancholy. It would see the children scrambling to gather up the sweets until their hands can’t hold any more; the one who hits another to gain a time advantage over a limited resource; the father who lectures another kid to share their excessive haul; the overwhelmed youngster crying in a corner; the exchanges on the official market and the black market, and the societies of parents who form like micro-governments to avoid what Garrett Hardin called the tragedy of the commons.
I, me, mine and other permutations by George (#ulink_f56a74c3-6582-5fd7-a965-33a5356091c8)
Long before becoming great jurists, philosophers, or noted economists, children – including the children that Aristotle, Plato and Piaget once were – already had intuitions about property and ownership. In fact, children use the pronouns my and mine before using I or their own names. This language progression reflects an extraordinary fact: the idea of ownership precedes the idea of identity, not the other way around.
In early battles over property the principles of law are also rehearsed. The youngest children claim ownership of something based on the argument of their own desires: ‘It’s mine because I want it.’
Later, around two years of age, they begin to argue with an acknowledgement of others’ rights to claim the same property for themselves. Understanding others’ ownership is a way of discovering that there are other individuals. The first arguments outlined by children are usually: ‘I had it first’; ‘They gave it to me.’ This intuition that the first person to touch something wins indefinite rights to its usage does not disappear in adulthood. Heated discussions over a parking spot, a seat on a bus, or the ownership of an island by the first country to plant its flag there are private and institutional examples of these heuristics. Perhaps because of that, it is unsurprising that large social conflicts, like in the Middle East, are perpetuated by very similar arguments to those deployed in a dispute between two-year-olds: ‘I got here first’; ‘They gave it to me.’
Transactions in the playground, or the origin of commerce and theft (#ulink_a3729c77-5552-5702-956b-bef1f0b11a61)
On the local 5-a-side football pitch, the owner of the ball is, to a certain extent, also the owner of the game. It gives them privileges like deciding the teams, and declaring when the game ends. These advantages can also be used to negotiate. The philosopher Gustavo Faigenbaum, in Entre Ríos, Argentina, and the psychologist Philippe Rochat, in Atlanta, in the USA, set out to understand this world: basically, how the concept of owning and sharing is established in children, among intuitions, praxis and rules. Thus they invented the sociology of the playground. Faigenbaum and Rochat, in their voyage to the land of childhood,
researched swapping, gifts and other transactions that took place in a primary school playground. Studying the exchange of little figurines, they found that even in the supposedly naïve world of the playground, the economy is formalized. As children grow up, lending and the assignment of vague, future values give way to more precise exchanges, the notion of money, usefulness and the prices of things.
As in the adult world, not all transactions in the country of childhood are licit. There are thefts, scams and betrayals. Rousseau’s conjecture is that the rules of citizenship are learned in discord. And it is the playground, which is more innocuous than real life, that becomes the breeding ground in which to play at the game of law.
The contrasting observations of Wynn and her colleagues suggest that very young children should already be able to sketch out moral reasoning. On the other hand, the work of Piaget, who is an heir to Rousseau’s tradition, indicates that moral reasoning only begins at around six or seven years old. Gustavo Faigenbaum and I set out to reconcile these different great thinkers in the history of psychology. And, along the way, to understand how children become citizens.
We showed to a group of children between four and eight years of age a video with three characters: one had chocolates, the other asked to borrow them and the third stole them. Then we asked a series of questions to measure varying degrees of depth of moral comprehension; if they preferred to be friends with the one who stole or the one who borrowed
(and why), and what the thief had to do to make things right with the victim. In this way we were able to investigate the notion of justice in playground transactions.
Our hypothesis was that the preference for the borrower over the thief, an implicit manifestation of moral preferences – as in Wynn’s experiments – should already be established even for the younger kids. And, to the contrary, the justification of these options and the understanding of what had to be done to compensate for the damage caused – as in Piaget’s experiments – should develop at a later stage. That is exactly what we proved. In the room with the four-year-olds, the children preferred to play with the borrower rather than with the thief. We also discovered that they preferred to play with someone who stole under extenuating circumstances than with aggravating ones.
But our most interesting finding was this: when we asked four-year-old children why they chose the borrower over the thief or the one who robbed in extenuating circumstances over the one who did so in aggravating ones, they gave responses like ‘Because he’s blond’ or ‘Because I want her to be my friend.’ Their moral criteria seemed completely blind to causes and reasons.
Here we find again an idea which has appeared several times in this chapter. Children have very early (often innate) intuitions – what the developmental psychologists Liz Spelke and Susan Carey refer to as core knowledge. These intuitions are revealed in very specific experimental circumstances, in which children direct their gaze or are asked to choose between two alternatives. But core knowledge is not accessible on demand in most real-life situations where it may be needed. This is because at a younger age core knowledge cannot be accessed explicitly and represented in words or concrete symbols.
Specifically, in the domain of morality, our results show that children have from a very young age intuitions about ownership which allow them to understand whether a transaction is licit or not. They understand the notion of theft, and they even comprehend subtle considerations which extenuate or aggravate it. These intuitions serve as a scaffold to forge, later in development, a formal and explicit understanding of justice.
But every experiment comes with its own surprises, revealing unexpected aspects of reality. This one was no exception. Gustavo and I came up with the experiment to study the price of theft. Our intuition was that the children would respond that the chocolate thief should give back the two they stole plus a few more as compensation for the damages. But that didn’t happen. The vast majority of the children felt that the thief had to return exactly the two chocolates that had been stolen. What’s more, the older the kids, the higher the fraction of those who advocated an exact restitution. Our hypothesis was mistaken. Children are much more morally dignified than we had imagined. They understood that the thieves had done wrong, that they would have to make up for it by returning what they’d stolen along with an apology. But the moral cost of the theft could not be resolved in kind, with the stolen merchandise. In the children’s justice, there was no reparation that absolved the crime.
If we think about the children’s transactions as a toy model of international law, this result, in hindsight, is extraordinary. An implicit, though not always respected, norm of international conflict resolution is that there should be no escalation in reprisal. And the reason is simple. If someone steals two and, in order to settle a peace, the victim demands four, the exponential growth of reprisals would be harmful for everyone. Children seem to understand that even in war there ought to be rules.
Jacques, innatism, genes, biology, culture and an image (#ulink_63343d7d-9aea-5a6f-9b04-6fa04b6003e9)
Jacques Mehler is one of many Argentinian political and intellectual exiles. He studied with Noam Chomsky at the Massachusetts Institute of Technology (MIT) at the heart of the cognitive revolution. From there he went to Oxford and then France, where he was the founder of the extraordinary school of cognitive science in Paris. He was exiled not just as a person, but as a thinker. He was accused of being a reactionary for claiming that human thought had a biological foundation. It was the oft-mentioned divorce between human sciences and exact sciences, which in psychology was particularly marked. I like to think of this book as an ode to and an acknowledgment of Jacques’s career. A space of freedom earned by an effort that he began, swimming against the tide. An exercise in dialogue.
In the epic task of understanding human thought, the division between biology, psychology and neuroscience is a mere declaration of caste. Nature doesn’t care a fig for such artificial barriers between types of knowledge. As a result, throughout this chapter, I have interspersed biological arguments, such as the development of the frontal cortex, with cognitive arguments, such as the early development of moral notions. In other examples, like that of bilingualism and attention, we’ve delved into how those arguments combine.
Our brains today are practically identical to those of at least 60,000 years ago, when modern man migrated from Africa and culture was completely different. This shows that individuals’ paths and potential for expression are forged within their social niches. One of the arguments of this book is that it is also virtually impossible to understand human behaviour without taking into consideration the traits of the organ that comprises it: the brain. The way in which social knowledge and biological knowledge interact and complement each other depends, obviously, on each case and its circumstances. There are some cases in which biological constitution is decisive. And others are determined primarily by culture and the social fabric. It is not very different from what happens with the rest of the body. Physiologists and coaches know that physical fitness can change enormously during our life while, on the other hand, our running speed, for example, doesn’t have such a wide range of variation.
The biological and the cultural are always intrinsically related. And not in a linear manner. In fact, a completely unfounded intuition is that biology precedes behaviour, that there is an innate biological predisposition that can later follow, through the effect of culture, different trajectories. That is not true; the social fabric affects the very biology of the brain. This is clear in a dramatic example observed in the brains of two three-year-old children. One is raised with affection in a normal environment while the other lacks emotional, educational and social stability. The brain of the latter is not only abnormally small but its ventricles, the cavities through which cerebrospinal fluid flows, have an abnormal size as well.
So different social experiences result in completely distinct brains. A caress, a word, an image – every life experience leaves a trace in the brain. These traces modify the brain and, with it, one’s way of responding to things, one’s predisposition to relating to someone, one’s desires, wishes and dreams. In other words, the social context changes the brain, and this in turn defines who we are as social beings.
A second unfounded intuition is thinking that because something is biological it is unchangeable. Again, this is simply not true. For instance, the predisposition to music depends on the biological constitution of the auditory cortex. This is a causal relation between an organ and a cultural expression. However, this connection does not imply developmental determinism. The auditory cortex is not static, anyone can change it just by practising and exercising.
Thus the social and the biological are intrinsically related in a network of networks. This categorical division is not a property of nature, but rather of our obtuse way of understanding it.
CHAPTER TWO (#ulink_b6a5ca8d-5016-547a-9675-ab20b69381a8)
The fuzzy borders of identity (#ulink_b6a5ca8d-5016-547a-9675-ab20b69381a8)
What defines our choices and allows us to trust other people and our own decisions?
Our choices define us. We choose to take risks or live conservatively, to lie when it seems convenient or to make the truth a priority, no matter what the cost. We choose to save up for a distant future or live in the moment. The vast sum of our actions comprises the outline of our identities. As José Saramago put it in his novel All the Names: ‘We don’t actually make decisions, the decisions make us.’ Or, in a more contemporary version, when Albus Dumbledore lectures Harry Potter: ‘It is our choices, Harry, that show what we truly are, far more than our abilities.’
Almost all decisions are mundane, because the overwhelming majority of our lives are spent in the day-to-day. Deciding whether we’ll visit a friend after work, if we should take the bus or the Underground; choosing between chips or a salad. Imperceptibly, we compare the universe of possible options on a mental scale, and after thinking it over we finally choose (chips, of course). When choosing between these alternatives, we activate the brain circuits that make up our mental decision-making machine.
Our decisions are almost always made based on incomplete information and imprecise data. When a parent chooses what school to send their child to, or a Minister of Economics decides to change the tax policy, or a football player opts to shoot at goal instead of passing to a teammate in the penalty area – in each and every one of these occasions it is only possible to sketch an approximate idea of the impending consequences of our decisions. Making decisions is a bit like predicting the future, and as such is inevitably imprecise. Eppur si muove. The machine works. That is what’s most extraordinary.
Churchill, Turing and his labryinth (#ulink_d40459ba-9774-5cea-9d6a-669164eb9d5f)
On 14 November 1940, some 500 Luftwaffe planes flew, almost unchallenged, to Britain and bombed the industrial city of Coventry for seven hours. Many years after the war had ended, Captain Frederick William Winterbotham revealed that Winston Churchill
could have avoided the bombing and the destruction of the city if he had decided to use a secret weapon discovered by the young British mathematician Alan Turing.
Turing had achieved a scientific feat that gave the Allies a strategic advantage that could decide the outcome of the Second World War. He had created an algorithm capable of deciphering Enigma, the sophisticated mechanical system made of circular pieces – like a combination lock – that allowed the Nazis to encode their military messages. Winterbotham explained that, with Enigma decoded, the secret service men had received the coordinates for the bombing of Coventry with enough warning to take preventive measures. Then, in the hours leading up to the bombing, Churchill had to decide between two options: one emotional and immediate – avoiding the horror of a civilian massacre – and the other rational and calculated – sacrificing Coventry, not revealing their discovery to the Nazis, and holding on to that card in order to use it in the future. Churchill decided, at a cost of 500 civilian lives, to keep Britain’s strategic advantage over his German enemies a secret.
Turing’s algorithm evaluated in unison all the configurations – each one corresponding to a possible code – and, according to its capacity to predict a series of likely messages, updated each configuration’s probability. This procedure continued until the likelihood of one of the configurations reached a sufficiently high level. The discovery, in addition to precipitating the Allied victory, opened up a new window for science. Half a century after the war’s end it was discovered that the algorithm that Turing had come up with to decode Enigma was the same one that the human brain uses to make decisions. The great English mathematician, who was one of the founders of computation and artificial intelligence, created – in the urgency of wartime – the first, and still the most effective, model for understanding what happens in our brains when we make a decision.
Turing’s brain (#ulink_ff2b3f46-3744-54fa-b2c7-70d0a0f30f03)
As in the procedure sketched out by Turing, the cerebral mechanism for making decisions is built on an extremely simple principle: the brain elaborates a landscape of options and starts a winner-take-all race between them.
The brain converts the information it has gathered from the senses into votes for one option or the other. The votes pile up in the form of ionic currents accumulated in a neuron until they reach a threshold where the brain deems there is sufficient evidence. These circuits that coordinate decision-making in the brain were discovered by a group of researchers headed by William Newsome and Michael Shadlen. Their challenge was to design an experiment simple enough to be able to isolate each element of the decision and, at the same time, sophisticated enough to represent decision-making in real life.
This is how the experiment works: a cloud of dots moves on a screen. Many of the dots move in a chaotic, disorganized way. Others move coherently, in a single direction. A player (an adult, a child, a monkey and, sometimes, a computer) decides which way that cloud of dots is moving. It is the electronic version of a sailor lifting a finger to decide, in the midst of choppy waters, which way the wind is blowing. Naturally, the game becomes easier when more dots are moving in the same direction.
Monkeys played this game thousands of times, while the researchers recorded their neuronal activity as reflected by the electrical currents produced in their brains. After studying this exercise for many years, and in many variations, they revealed the three principles of Turing’s algorithm for decision-making:
(1) A group of neurons in the visual cortex receives information from the retina. The neuron’s current reflects the quantity and direction of movement in each moment, but does not accumulate a history of these observations.
(2) The sensory neurons are connected to other neurons in the parietal cortex, which amass this information over time. So the neuronal circuits of the parietal cortex codify how the predisposition towards each possible action changes over time during the course of making the decision.
(3) As information favouring one option accumulates, the parietal cortex that codifies this option increases its electrical activity. When the activity reaches a certain threshold, a circuit of neurons in structures deep in the brain – known as basal ganglia – set off the corresponding action and restart the process to make way for the next decision.
The best way to prove that the brain decides through a race in the parietal cortex is by showing that a monkey’s response can be conditioned by injecting a current into the neurons that codify evidence in favour of a certain option. Shalden and Newsome did that experiment. While one monkey was watching a cloud of dots that moved completely randomly, they used an electrode to inject an electrical current into the parietal neurons that codify movement to the right. And, despite the senses indicating that movement was tied in either direction, the monkeys always responded that they were moving to the right. This is like emulating electoral fraud, manually inserting certain votes into the ballot box.
Additionally, this series of experiments allowed for the identification of three fundamental traits of the decision-making process. What relationship is there between the clarity of the evidence and the time we take to make a decision? How are options biased by prejudices or prior knowledge? When is there enough evidence in favour of one option to call the race? The answers to these three questions are interrelated. The more incomplete the information is, the slower the accumulation of evidence will be. In the moving-dot experiment, when almost all the dots move at random, the ramp of activation in the neurons in the parietal cortex that amass the evidence is not very steep. And if the threshold of evidence needed remains the same, it will take more time to cross it; which is to say, to reach the same degree of reliability. The decision cooks over a slow flame, but eventually it will reach the same temperature.
And how is the threshold established? Or, to put it another way, how does the brain determine when enough is enough? This depends on a calculation that the brain makes in a stunningly precise way, by pondering the cost of making a mistake and the time available for the decision-making.
The brain determines that threshold in order to optimize the gains from a decision. To do so it combines neuronal circuits that codify:
(1) The value of the action.
(2) The cost of time invested.
(3) The quality of the sensory information.
(4) An endogenous urgency to respond, something that we recognize as anxiety or impatience to decide.
If, in the random-dots game, mistakes are punished severely, the players (humans or monkeys) raise the threshold, taking more time to decide and accumulating more evidence. If, on the other hand, mistakes don’t count, then the players lower that same threshold, adopting again the best strategy, which here is to respond as quickly as possible. The most notable aspect of this adaptive adjustment is that in most cases it is not conscious, and often far more optimal than we would imagine.
Consider, for example, a driver stopping at a traffic light. The driver’s brain is making a great number of estimations: the probability that the light may turn amber or red, the distance to the crossing, the speed of the car, the effectiveness of the brakes, the traffic etc. Not only this: the driver´s brain is also pondering the urgency, the consequences of an accident … In the vast majority of cases (except when something goes wrong and the monitoring system of the brain takes control) these considerations are not explicit. We are not aware of all these calculations. Yet our brains do make this sophisticated calculus, which results in a decision of when and how hard we will hit the brake pedal. This specific example reveals a general principle: decision-makers know much more than they believe they do.
In contrast with this, in some conscious deliberations (which are the only ones we do remember at the end of the day) the brain often sets a very inefficient threshold to reach a decision. We all remember having slept too long on some matters which did not require that much deliberation. For example, most of us recall deliberating ad infinitum in a restaurant between two choices even if deep inside we know we would greatly enjoy either of those two options.
Turing in the supermarket (#ulink_835d021a-5263-5dbe-9417-f228c8882b7e)
Even though in the laboratory we study simple decisions, what we are ultimately more interested in revealing is how the brain makes everyday decisions: the driver who decides whether or not to jump an amber light; the judge who condemns or exonerates a defendant; the voter who casts a ballot for one candidate or another; the shopper who takes advantage of or falls victim to a special deal. The conjecture is that all of these decisions, despite belonging to different realms and having their own idiosyncrasies, are the result of the same decision-making mechanism.
One of the main principles of this procedure, which is at the heart of Turing’s design, consists in how one realizes when it is time to stop gathering evidence. The problem is reflected in the paradox described by a medieval philosopher, Jean Buridan: a donkey hesitates endlessly between two identical piles of hay and, as a result, ends up dying of hunger. In fact, the paradox presents a problem for Turing’s pure model. If the number of votes in favour of each alternative is identical, the cerebral race is stuck in a tie. The brain has a way of avoiding the tie: when it considers that sufficient time has passed, it invents neuronal activity that it randomly distributes among the circuits that codify each option. Since this current is random, one of the options ends up having more votes and, as such, wins the race. It’s as if the brain tossed a coin and let fate break the tie. How much time is reasonable for making a decision depends on internal states of the brain – for example, if we are more or less anxious – and on external factors that affect how the brain counts the time.
One of the ways that the brain estimates time is simply by counting pulses: steps, heartbeats, breaths, the swinging of a pendulum or music’s tempo. For example, when we exercise, we mentally estimate a minute faster than when we are at rest, because each heartbeat – and therefore each pulse of our inner clock – is quicker. The same happens with tempo in music. The clock accelerates with the rhythm and, thus, time passes more rapidly. Do these changes in our internal clock make us decide more quickly and lower our decision threshold?
Indeed, music has much more direct consequences for our decisions than we recognize. We drive, shop and walk differently depending on the music we are listening to at the time. As the musical tempo rises, our decision-making threshold lowers and as a result risk increases in almost every decision. Drivers change lanes more frequently, go through more amber lights, overtake and exceed the speed limit more while driving as the speed of the music they are listening to increases. Musical tempo also dictates the amount of time we are willing to wait patiently in a waiting room or the number of products we tend to buy in a supermarket. Many supermarket managers know that the piped-in music is a key to sales and use that to their advantage, with no need to be familiar with Turing’s work. That’s how predictable our decision-making machine is, yet we are almost completely unaware of its workings.
Another key factor that affects the decision-making machine is determining where the race begins. When there is a bias towards one of the alternatives, the neurons that accumulate information in its favour start with an initial electrical charge, which is similar to giving them a head start in the race. In some cases, biases can have a fundamental influence; for example, in the decision to donate organs.
Demographic studies of organ donation group different countries into two classes: those in which almost all the inhabitants agree to donate organs, and another in which almost no one does. It doesn’t take a master statistician to understand that what’s striking is the absence of intermediate classes. The reason turns out to be extremely simple: what ends up determining whether a person chooses to donate organs is the wording on the form. In the countries where the form says: ‘If you wish to donate organs, sign here’, no one does. On the other hand, in countries where it says: ‘If you do NOT wish to donate organs, sign here’, almost everyone donates. The explanation for both phenomena comes from an almost universal trait that has nothing to do with religion or life and death but rather just that no one fills out the form completely.
When we are offered a wide variety of options, they don’t all start running from the same point; those that are given by default begin with an advantage. If, in addition, the problem is one that is hard to resolve, meaning that evidence in favour of any of the options is scarce, the one that started out with the advantage wins. This is a very clear example of how governments can guarantee freedom of choice but, at the same time, bias – and, in practice, dictate – what we decide. But this also reveals a characteristic of human beings, be they Dutch, Mexican, Catholic, Protestant or Muslim: our decision-making mechanism collapses when faced with difficult situations. Then we merely accept what we are offered, by default.
The tell-tale heart (#ulink_49eee215-0191-51a2-99dd-3e7f3e0fcb91)
Until now we’ve talked about decision-making processes as if they were all of one class, governed by the same principles and carried out in the brain by similar circuits. However, we all perceive that the decisions we make belong to at least two qualitatively distinct types; some are rational and we can put forward the arguments behind them. Others are hunches, inexplicable decisions that feel as if they are dictated by our bodies. But are there really two different ways of deciding? Is it better to choose something based on our intuitions, or to carefully and rationally deliberate each decision?
In general we associate rationality with science, while the nature of our emotions seems mysterious, esoteric and essentially inexplicable. We will topple this myth with a simple experiment.
Two neuroscientists, Lionel Naccache and Stanislas Dehaene – my mentor in Paris – did an experiment in which they flashed numbers on screens so fleetingly that the participants believed they’d seen nothing. This type of presentation, which doesn’t activate consciousness, is called subliminal. Then they ask the participants to say if the number is higher or lower than five and, much to their own surprise, they answer correctly in most cases. The person making the decision perceives it as a hunch, but from the experimenter’s perspective it is clear that the decision was induced unconsciously with a mechanism very similar to that of conscious decision-making.
Which is to say that, in the brain, hunches aren’t so different from rational decisions. But the previous example doesn’t capture all the richness of the physiology of unconscious decisions. In this case, popular expressions such as ‘trust your heart’ or ‘go with your gut feelings’ turn out to be quite accurate and shed light on how intuitions are forged.
All it takes to understand this is putting a pencil between your teeth, lengthwise. Inevitably, your lips will rise in an imitation of a smile. This is obviously a mechanical effect, not a reflection of an emotion. But that doesn’t matter, it still gives a certain sense of wellbeing. The mere gesture of the smile is enough. A film scene will seem more entertaining to us if we watch it with a pencil held in our mouth that way than if we hold it between our lips, as if scowling. So, deciding whether something is fun or boring does not only originate in an evaluation of the external world, but in visceral reactions produced in our internal worlds. Crying, sweating, trembling, increasing heart rate or secreting adrenaline are not merely reactions by the body to communicate an emotion. Instead, the brain reads and identifies these bodily variables to encode and produce feelings and emotions.
That corporeal states can affect our decision-making process is a physiological and scientific demonstration of what we perceive as a hunch. When making a decision unconsciously, the cerebral cortex evaluates different alternatives and, in doing so, estimates the possible risks and benefits of each option. The result of this computation is expressed in corporeal states through which the brain can recognize risk, danger or pleasure. The body becomes a reflection and a resonating chamber of the external world.
The body in the casino and at the chessboard (#ulink_be99c37e-7899-5685-9d33-d70c85b9e5c5)
The key experiment showing how decisions are based on hunches was done with two decks of cards.
As in so many board games, this experiment employs ingredients from real life decision-making: winnings, losses, uncertainty and risk. The game is simple but unpredictable. In each turn, the player merely chooses which deck to pick a card from. The number of the card chosen indicates the coins that the player wins (or loses if it’s negative). Since the cards are turned face down, the player has to evaluate, over the course of the entire experiment, which of the two decks is more profitable.
This is like someone in a casino who has to choose between two one-armed bandits just by observing how many times and how much each one pays out over a period of time. But, unlike in the casino, this game thought up by a neurobiologist, Antonio Damasio, is not purely random: there is one deck that on average pays out more than the other. If this rule is discovered, then the next step is simple: always choose the deck that pays more. Lo and behold, an infallible system.
The difficulty lies in the fact that the player has to discover this rule through pondering a long history of payouts amid large fluctuations. After much practice, almost everyone discovers the rule, is able to explain it and, naturally, starts to choose cards from the correct deck every time. But the real finding happens along the way to this discovery, among intuitions and hunches. Even before being able to articulate the rule, the players start to play well and more frequently choose cards from the correct deck. In this phase, despite playing much better than when they were choosing randomly, the players cannot explain why they opt for the correct deck (the one that pays out more in the long term). Sometimes they don’t even know they are choosing one deck more than the other. But unequivocal signs show up in their bodies. In this part of the experiment, when players are about to choose the incorrect deck, their skin conductance increases, indicating a rise in sweating, which is in turn a reflection of an emotional state. Which is to say that the players cannot explain that one of the decks gives better results than the other, but their bodies already know it.
My colleague María Julia Leone, a neuroscientist and international chess master, and I carried out this experiment on the chessboard, following the Borgesian concept of chess as a metaphor for life. Two masters face off. They have thirty minutes to make a series of decisions that will organize their armies. On the board, it is a battle to the death and emotions are running high. During the game we trace the players’ heartbeats. Heart rate – just like stress – increases over the course of the game, as time runs out and the end of the battle approaches. Their heart rates also spike when their opponent commits an error that will decide the outcome of the game.
