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This patient felt so challenged by suddenly gaining sight because while his eyes had been ‘opened’ by the surgery, he still had to learn to see. It was a big and tiresome effort to put together the new visual experience with the conceptual world he had built through his senses of hearing and touch. Meltzoff proved that the human brain has the ability to establish spontaneous correspondences between sensory modalities. And Valvo showed that this ability atrophies when in disuse over the course of a blind life.
On the contrary, when we experience different sensory modalities, some correspondences between them consolidate spontaneously over time. To prove this, my friend and colleague Edward Hubbard, along with Vaidyanathan Ramachandran, created the two shapes that we see here. One is Kiki and the other is Bouba. The question is: which is which?
Almost everyone answers that the one on the left is Bouba and the one on the right is Kiki. It seems obvious, as if it couldn’t be any other way. Yet there is something strange in that correspondence; it’s like saying someone looks like a Carlos. The explanation for this is that when we pronounce the vowels /o/y/u/, our lips form a wide circle, which corresponds to the roundness of Bouba. And when saying the /k/, or /i/, the back part of the tongue rises and touches the palate in a very angular configuration. So the pointy shape naturally corresponds with the name Kiki.
These bridges often have a cultural basis, forged by language. For example, most of the world thinks that the past is behind us and the future is forward. But that is arbitrary. For example, the Aymara, a people from the Andean region of South America, conceive of the association between time and space differently. In Aymara, the word ‘nayra’ means past but also means in front, in view. And the word ‘quipa’, which means future, also indicates behind. Which is to say that in the Aymaran language the past is ahead and the future behind. We know that this reflects their way of thinking, because they also express that relationship with their bodies. The Aymara extend their arms backwards to refer to the future and forwards to allude to the past. While on the face of it this may seem strange, when they explain it, it seems so reasonable that we feel tempted to change our own way of envisioning it; they say that the past is the only thing we know – what our eyes see – and therefore it is in front of us. The future is the unknown – what our eyes do not know – and thus it is at our backs. The Aymara walk backwards through their timeline. Thus, the uncertain, unknown future is behind and gradually comes into view as it becomes the past.
We designed an atypical experiment, with the linguist Marco Trevisan and the musician Bruno Mesz, in order to find out whether there is a natural correspondence between music and taste. The experiment brought together musicians, chefs and neuroscientists. The musicians were asked to improvise on the piano, based on the four canonical flavours: sweet, salty, sour and bitter. Of course, coming from different musical schools and styles (jazz, rock, classical, etc.) each one of them had their own distinctive interpretation. But within that wide variety we found that each taste inspired consistent patterns: the bitter corresponded with deep, continuous tones; the salty with notes that were far apart (staccato); the sour with very high-pitched, dissonant melodies; and the sweet with consonant, slow and gentle music. In this way we were able to salt ‘Isn’t She Lovely’by Stevie Wonder and to make a sour version of The White Album by the Beatles.
The mirror between perception and action (#ulink_5924f4db-a487-59dc-967e-53e4c31c9899)
Our representation of time is random and fickle. The phrase ‘Christmas is fast approaching’ is strange. Approaching from where? Does it come from the south, the north, the west? Actually, Christmas isn’t located anywhere. It is in time. This phrase, or the analogous one, ‘we’re getting close to the end of the year’, reveals something of how our minds organize our thoughts. We do it in our bodies. Which is why we talk of the head of government, of someone’s right-hand man, the armpit of the world and many other metaphors
that reflect how we organize thought in a template defined by our own bodies. And because of that, when we think of others’ actions, we do so by acting them out ourselves, speaking others’ words in our own voice, yawning someone else’s yawn and laughing someone else’s laugh. You can do a simple experiment at home to test out this mechanism. During a conversation, cross your arms. It’s very likely that the person you are speaking to will do the same. You can take it further with bolder gestures, like touching your head, or scratching yourself, or stretching. The probability that the other person will imitate you is high.
This mechanism depends on a cerebral system made up of mirror neurons. Each one of these neurons codifies specific gestures, like moving an arm or opening up a hand, but it does so whether or not the action is our own or someone else’s. Just as the brain has a mechanism that spontaneously amalgamates information from different sensory modes, the mirror system allows – also spontaneously – our actions and others’ actions to be brought together. Lifting your arm and watching someone else do it are very different processes, since one is done by you and the other is not. As such, one is visual and the other is motor. However, from a conceptual standpoint, they are quite similar. They both correspond to the same gesture in the abstract world.
And now after understanding how we adults merge sensory modalities in music, in shapes and sounds and in language, and how we bring together perception and action, we go back to the infant mind, specifically to ask whether the mirror system is learned or whether it is innate. Can newborns understand that their own actions correspond to the observation of another person’s? Meltzoff also tested this out, to put an end to the empirical idea that considers the brain a tabula rasa.
Meltzoff proposed another experiment, in which he made three different types of face at a baby: sticking out his tongue, opening his mouth, and pursing his lips as if he were about to give the child a kiss. He observed that the baby tended to repeat each of his gestures. The imitation wasn’t exact or synchronized; the mirror is not a perfect one. But, on average, it was much more likely that the baby would replicate the gesture he or she observed than make one of the other two. Which is to say that newborns are capable of associating observed actions with their own, although the imitation is not as precise as it will later become when language is introduced.
Meltzoff’s two discoveries – the associations between our actions and those of others, and between varying sensory modalities – were published in 1977 and 1979. By 1980, the empirical dogma was almost completely dismantled. In order to deal it a final death blow, there was one last mystery to be solved: Piaget’s mistake.
Piaget’s mistake! (#ulink_e5a4d892-38c4-5145-aca8-fb45826b382c)
One of the loveliest experiments done by the renowned Swiss psychologist Jean Piaget is the one called A-not-B. The first part goes like this: there are two napkins on a table, one on each side. A ten-month-old baby is shown an object, then it is covered with the first napkin (called ‘A’). The baby finds it without difficulty or hesitation.
Behind this seemingly simple task is a cognitive feat known as object permanence: in order to find the object there must be a reasoning that goes beyond what is on the surface of the senses. The object did not disappear. It is merely hidden. A baby that is to be able to comprehend this must have a view of the world in which things do not cease to exist when we no longer see them. That, of course, is abstract.
The second part of the experiment begins in exactly the same way. The same ten-month-old baby is shown an object, which is then covered up by napkin ‘A’. But then, and before the baby does anything, the person running the experiment moves the object to underneath the other napkin (called ‘B’), making sure that the baby sees the switch. And here is where it gets weird: the baby lifts the napkin where it was first hidden, as if not having observed the switch just made in plain sight.
This error is ubiquitous. It happens in every culture, almost unfailingly, in babies about ten months of age. The experiment is striking and precise, and shows fundamental traits of our way of thinking. But Piaget’s conclusion, that babies of this age still do not fully understand the abstract idea of object permanence, is erroneous.
When revisiting the experiment, decades later, the more plausible – and much more interesting – interpretation is that babies know the object has moved but cannot use that information. They have, as happens in a state of drunkenness, a very shaky control of their actions. More precisely, ten-month-old babies have not yet developed a system of inhibitory control, which is to say, the ability to prevent themselves doing something they had already planned to do. In fact, this example turns out to be the rule. We will see in the next section how certain aspects of thought that seem sophisticated and elaborated – morality or mathematics, for example – are already sketched from the day we are born. On the other hand, others that seem much more rudimentary, like halting a decision, mature gradually and steadily. To understand how we came to know this, we need to take a closer look at the executive system, or the brain’s ‘control tower’, which is formed by an extensive neural network distributed in the prefrontal cortex that matures slowly during childhood.
The executive system (#ulink_05720afe-82ae-58d3-ab57-a011d7cbb060)
The network in the frontal cortex that organizes the executive system defines us as social beings. Let’s give a small example. When we grab a hot plate, the natural reflex would be to drop it immediately. But an adult, generally, will inhibit that reflex while quickly evaluating if there is a nearby place to set it down and avoid breaking the plate.
The executive system governs, controls and administers all these processes. It establishes plans, resolves conflicts, manages our attention focus, and inhibits some reflexes and habits. Therefore the ability to govern our actions depends on the reliability of the executive function system.
If it does not work properly, we drop the hot plate, burp at the table, and gamble away all our money at the roulette wheel.
The frontal cortex is very immature in the early months of life and it develops slowly, much more so than other brain regions. Because of this, babies can only express very rudimentary versions of the executive functions.
A psychologist and neuroscientist, Adele Diamond, carried out an exhaustive and meticulous study on physiological, neurochemical and executive function development during the first year of life. She found that there is a precise relationship between some aspects of the development of the frontal cortex and babies’ ability to perform Piaget’s A-not-B task.
What impedes a baby’s ability to solve this apparently simple problem? Is it that babies cannot remember the different positions the object could be hidden in? Is it that they do not understand that the object has changed place? Or is it, as Piaget suggested, that the babies do not even fully understand that the object hasn’t ceased to exist when it is hidden under a napkin? By manipulating all the variables in Piaget’s experiment – the number of times that babies repeat the same action, the length of time they remember the position of the object, and the way they expresses their knowledge – Diamond was able to demonstrate that the key factor impeding the solution of this task is babies’ inability to inhibit the response they have already prepared. And with this, she laid the foundations of a paradigm shift: children don’t always need to learn new concepts; sometimes they just need to learn how to express the ones they already know.
The secret in their eyes (#ulink_07037fd5-d614-5c44-b5fc-8dd21a85332e)
So we know that ten-month-old babies cannot resist the temptation to extend their arms where they were planning to, even when they understand that the object they wish to reach has changed location. We also know that this has to do with a quite specific immaturity of the frontal cortex in the circuits and molecules that govern inhibitory control. But how do we know if babies indeed understand that the object is hidden in a new place?
The key is in their gaze. While babies extend their arms towards the wrong place, they stare at the right place. Their gazes and their hands point to different locations. Their gaze shows that they know where it is; their hand movement shows that they cannot inhibit the mistaken reflex. They are – we are – two-headed monsters. In this case, as in so many others, the difference between children and adults is not what they know but rather how they are able to act on the basis of that knowledge.
In fact, the most effective way of figuring out what children are thinking is usually by observing their gaze.
Going with the premise that babies look more at something that surprises them, a series of games can be set up in order to discover what they can distinguish and what they cannot, and this can give answers as to their mental representations. For example, that was how it was discovered that babies, a day after being born, already have a notion of numerosity, something that previously seemed impossible to determine.
The experiment works like this. A baby is shown a series of images. Three ducks, three red squares, three blue circles, three triangles, three sticks … The only regularity in this sequence is an abstract, sophisticated element: they are all sets of three. Later the baby is shown two images. One has three flowers and the other four. Which do the newborns look at more? The gaze is variable, of course, but they consistently look longer at the one with four flowers. And it is not that they are looking at the image because it has more things in it. If they were shown a sequence of groups of four objects, they would later look longer at one that had a group of three. It seems they grow bored of always seeing the same number of objects and are surprised to discover an image that breaks the rule.
Liz Spelke and Véronique Izard proved that the notion of numerosity persists even when the quantities are expressed in different sensory modalities. Newborns that hear a series of three beeps expect there then to be three objects and are surprised when that is not the case. Which is to say, babies assume a correspondence of amounts between the auditory experience and the visual one, and if that abstract rule is not followed through, their gaze is more persistent. These newborns have only been out of the womb for a matter of hours yet already have the foundations of mathematics in their mental apparatus.
Development of attention (#ulink_71da224d-2b12-5196-973c-527330be714c)
Cognitive faculties do not develop homogeneously. Some, like the ability to form concepts, are innate. Others, like the executive functions, are barely sketched in the first months of life. The most clear and concise example of this is the development of the attentional network. Attention, in cognitive neuroscience, refers to a mechanism that allows us to selectively focus on one particular aspect of information and ignore other concurrent elements.
We all sometimes – or often – struggle with attention. For example, when we are talking to someone and there is another interesting conversation going on nearby.
Out of courtesy, we want to remain focused on our interlocutor, but our hearing, gaze and thoughts generally direct themselves the other way. Here we recognize two ingredients that lead and orient attention: one endogenous, which happens from inside, through our own desire to concentrate on something, and the other exogenous, which happens due to an external stimulus. Driving a car, for example, is another situation of tension between those systems, since we want to be focused on the road but alongside it there are tempting advertisements, bright lights, beautiful landscapes – all elements that, as admen know well, set off the mechanisms of exogenous attention.
Michael Posner, one of the founding fathers of cognitive neuroscience, separated the mechanisms of attention
and found that they were made up of four elements:
(1) Endogenous orientation.
(2) Exogenous orientation.
(3) The ability to maintain attention.
(4) The ability to disengage it.
He also discovered that each of these processes involves different cerebral systems, which extend throughout the frontal, parietal and anterior cingulate cortices. In addition, he found that each one of these pieces of the attentional machinery develops at its own pace and not in unison.
For example, the system that allows us to orient our attention towards a new element matures much earlier than the system that allows us to disengage our attention. Therefore, voluntarily shifting our attention away from something is much more difficult than we imagine. Knowing this can be of enormous help when dealing with a child; a clear example is found in how to stop a small child’s inconsolable crying. A trick that some parents hit upon spontaneously, and emerges naturally when one understands attention development, is not asking their offspring to just cut it out, but rather to offer another option that attracts their attention. Then, almost by magic, the inconsolable crying stops ipso facto. In most cases, the baby wasn’t sad or in pain, but the crying was, actually, pure inertia. That this happens the same way for all children around the world is not magic or a coincidence. It reflects how we are – how we were – in that developmental period: able to draw our attention towards something when faced with an exogenous stimulus, and unable to voluntarily disengage.
Separating out the elements that comprise thought allows for a much more fluid relationship between people. No parent would ask a six-month-old to run, and they certainly wouldn’t be frustrated when it didn’t happen. In much the same way, familiarity with attentional development can avoid a parent asking a small child to do the impossible; for example, to just quit crying.
The language instinct (#ulink_1c6972be-ef75-5145-8e44-22ec20304158)
In addition to being connected for concept formation, a newborn’s brain is also predisposed for language. That may sound odd. Is it predisposed for French, Japanese or Russian? Actually, the brain is predisposed for all languages because they all have – in the vast realm of sounds – many things in common. This was the linguist Noam Chomsky’s revolutionary idea.
All languages have similar structural properties. They are organized in an auditory hierarchy of phonemes that are grouped into words, which in turn are linked to form sentences. And these sentences are organized syntactically, with a property of recursion that gives the language its wide versatility and effectiveness. On this empirical premise, Chomsky proposed that language acquisition in infancy is limited and guided by the constitutional organization of the human brain. This is another argument against the notion of the tabula rasa: the brain has a very precise architecture that, among other things, makes it ideal for language. Chomsky’s argument has another advantage, since it explains why children can learn language so easily despite its being filled with very sophisticated and almost always implicit grammatical rules.
This idea has now been validated by many demonstrations. One of the most intriguing was presented by Jacques Mehler, who had French babies younger than five days old listen to a succession of various phrases spoken by different people, both male and female. The only thing common to all the phrases was that they were in Dutch. Every once in a while the phrases abruptly changed to Japanese. He was trying to see if that change would surprise a baby, which would show that babies are able to codify and recognize a language.
In this case, the way to measure their surprise wasn’t the persistence of their gaze but the intensity with which they sucked on their dummies. Mehler found that when the language changed, the babies sucked harder – like Maggie Simpson – indicating that they perceived that something relevant or different was occurring. The key is that this did not happen when he repeated the same experiment with the sound of all the phrases reversed, like a record played backwards. That means that the babies didn’t have the ability to recognize categories from just any sort of sound but rather they were specifically tuned to process languages.
We usually think that innate is the opposite of learned. Another way of looking at it is thinking of the innate as actually something learned in the slow cooker of human evolutionary history. Following this line of reasoning, since the human brain is already predisposed for language at birth, we should expect to find precursors of language in our evolutionary cousins.
This is precisely what Mehler’s group proved by showing that monkeys also have auditory sensibilities attuned to language. Just like babies, tamarin monkeys reacted with the same surprise every time the language they were hearing in the experiment changed. As with babies, this was specific to language, and did not happen when phrases were played backwards.
This was a spectacular revelation, not to mention a gift for the media … ‘Monkeys Speak Japanese’ is a prime example of how to destroy an important scientific finding with a lousy headline. What this experiment proves is that languages are built upon a sensitivity of the primate brain to certain combinations of sounds This in turn may explain in part why most of us learn to understand spoken language so easily at a very young age.
Mother tongue (#ulink_ac6130a9-6771-57de-a0f5-d992aef7fb86)
Our brains are prepared and predisposed for language from the day we are born. But this predisposition does not seem to materialize without social experience, without using it with other people. This conclusion comes from studies of feral children who grow up without any human contact. One of the most emblematic is Kaspar Hauser, magnificently portrayed in the eponymous film directed by Werner Herzog. Kaspar Hauser’s story of confinement for the duration of his childhood
shows that it is very difficult to acquire language when it has not been practised early in life. The ability to speak a language, to a large extent, is learned in a community. If a child grows up in complete isolation from others, his or her ability to learn a language is largely impaired. Herzog’s film is, in many ways, a portrait of that tragedy.
The brain’s predisposition for a universal language becomes fine-tuned by contact with others, acquiring new knowledge (grammatical rules, words, phonemes) or unlearning differences that are irrelevant to one’s mother tongue.
The specialization of language happens first with phonemes. For example, in Spanish there are five vowel sounds, while in French, depending on the dialect, there are up to seventeen (including four nasal vowel sounds). Non-French speakers often do not perceive the difference between some of these vowel sounds. For instance, native Spanish speakers typically do not distinguish the difference between the sounds of the French words cou (pronounced [ku]) and cul (pronounced [ky]) which may lead to some anatomical misunderstanding since cou means neck and cul means bum. Vowels that they perceive as [u] in both cases sound completely different for a French speaker, as much so as an ‘e’ and an ‘a’ for Spanish speakers. But the most interesting part is that all the children of the world, French or not, can recognize those differences during the first few months of life. At that point in our development we are able to detect differences that as adults would be impossible for us.
In effect, a baby has a universal brain that is able to distinguish phonological contrasts in every language. Over time, each brain develops its own phonological categories and barriers that depend on the specific use of its language. In order to understand that an ‘a’ pronounced by different people, in varying contexts, at different distances, with head colds and without, corresponds to the same ‘a’, one has to establish a category of sounds. Doing this means, unfailingly, losing resolution. Those borders for identifying phonemes in the space of sounds are established between six and nine months of life. And they depend, of course, on the language we hear during development. That is the age when our brain stops being universal.
After the early stage in which phonemes are established, it is time for words. Here there is a paradox that, on the face of it, seems hard to resolve. How can babies know which are the words in a language? The problem is not only how to learn the meaning of the thousands of words that make it up. When someone hears a phrase in German for the first time, not only do they not know what each word means but they can’t even distinguish them in the sound continuum of the phrase. That is due to the fact that in spoken language there are no pauses that are equal to the space between written words. Thatmeansthatlisteningtosomeonespeakisliketryingtoreadthis.
And if babies don’t know which are the words of a language, how can they recognize them in that big tangle?
One solution is talking to babies – as we do when speaking Motherese – slowly and with exaggerated enunciation. In Motherese there are pauses between words, which facilitates the baby’s heroic task of dividing a sentence into the words that make it up.
But this doesn’t explain per se how eight-month-olds already begin to form a vast repertoire of words, many of which they don’t even know how to define. In order to do this, the brain uses a principle similar to the one many sophisticated computers employ to detect patterns, known as statistical learning. The recipe is simple and identifies the frequency of transitions between syllables and function. Since the word hello is used frequently, every time the syllable ‘hel’ is heard, there is a high probability that it will be followed by the syllable ‘lo.’ Of course, these are just probabilities, since sometimes the word will be helmet or hellraiser, but a child discovers, through an intense calculation of these transitions, that the syllable ‘hel’ has a relatively small number of frequent successors. And so, by forming bridges between the most frequent transitions, the child can amalgamate syllables and discover words. This way of learning, obviously not a conscious one, is similar to what smartphones use to complete words with the extension they find most probable and feasible; as we know, they don’t always get it right.
This is how children learn words. It is not a lexical process as if filling a dictionary in which each word is associated with its meaning or an image. To a greater extent, the first approach to words is rhythmic, musical, prosodic. Only later are they tinged with meaning. Marina Nespor, an extraordinary linguist, suggests that one of the difficulties of studying a second language in adulthood is that we no longer use that process. When adults learn a language, they usually do so deliberately and by using their conscious apparatus; they try to acquire words as if memorizing them from a dictionary and not through the musicality of language. Marina maintains that if we were to imitate the natural mechanism of first consolidating the words’ music and the regularities in the language’s intonation, our process of learning would be much simpler and more effective.
The children of Babel (#ulink_99398f97-c5fa-5963-95f9-19f59aeb5231)
One of the most passionately debated examples of the collision between biological and cultural predispositions is bilingualism. On one hand, a very common intuitive assumption is: ‘Poor child, just learning to talk is difficult, the kid’s gonna get all mixed up having to learn two languages.’ But the risk of confusion is mitigated by the perception that bilingualism implies a certain cognitive virtuosity.
Bilingualism, actually, offers a concrete example of how some social norms are established without the slightest rational reflection. Society usually considers monolingualism to be the norm, so that the performance of bilinguals is perceived as a deficit or an increment in relation to it. That is not merely convention. Bilingual children have an advantage in the executive functions, but this is never perceived as a deficit in monolinguals’ potential development. Curiously, the monolingual norm is not defined by its popularity; in fact, most children in the world grow up being exposed to more than one language. This is especially true in countries with large immigrant populations. In these homes, languages can be combined in all sorts of forms. As a boy, Bernardo Houssay (later awarded the Nobel Prize for Physiology) lived in Buenos Aires, Argentina (where the official language is Spanish) with his Italian grandparents. His parents spoke little of their parents’ language, and he and his brothers spoke none. So he believed that people, as they aged, turned into Italians.
Cognitive neuroscientific research has conclusively proven that, going against popular belief, the most important landmarks in language acquisition – the moment of comprehending the first words, the development of sentences, among others – are very similar in monolinguals and bilinguals. One of the few differences is that, during infancy, monolinguals have a bigger vocabulary. However, this effect disappears – and even reverts – when the words a bilingual can use in both languages are added to that vocabulary.
A second popular myth is that one shouldn’t mix languages and that each person should speak to a child always in the same language. That is not the case. Some studies in bilingualism are conducted with parents who each speak one language exclusively to their children, which is very typical in border regions, such as where Slovenia meets Italy. In other studies, in bilingual regions such as Quebec or Catalonia, both parents speak both languages. The developmental landmarks in these two situations are identical. And the reason why the babies don’t get confused by one person speaking two languages is because, in order to produce the phonemes of each language, they give gesticular indications – the way they move their mouths and face – of which language they are speaking. Let’s say that one makes a French or an Italian facial expression. These are easy clues for a baby to recognize.
On the other hand, another large group of evidence indicates that bilinguals have a better and faster development of the executive functions; more specifically, in their ability to inhibit and control their attention. Since these faculties are critical in a child’s educational and social development, the advantage of bilingualism now seems quite obvious.
In Catalonia, children grow up in a sociolinguistic context in which Spanish and Catalan are often used in the same conversation. As a consequence, Catalan children develop skills to shift rapidly from one language to the other. Will this social learning process extend to task-switching beyond the domain of language?
To answer this question, César Ávila with his colleagues compared brain activity of monolinguals and Catalan bilinguals who switched between non-linguistic tasks. Participants saw a sequence of objects flashing rapidly in the centre of a screen. For a number of trials they were asked to respond with a button if the object was red, and with another button if it was blue. Then, suddenly, participants were asked to forget about colour and respond using the same buttons about the shape of the object (right button for a square and left button for a circle).
As simple as this sounds, when task instructions switch from colour to shape most people respond more slowly and make more errors. This effect is much smaller in Catalonian bilinguals. Ávila also found that the brain networks used by monolinguals and bilinguals to solve this task are very different. It is not that bilinguals are just increasing slightly the amount of activity in one region; it is that the problem in the brain is solved in an altogether different manner.
To switch between tasks, monolinguals use brain regions of the executive system such as the anterior cingulate and some regions in the frontal cortex. Bilinguals instead engage brain regions of the language network, the same regions they engage to switch between Spanish and Catalan in a fluid conversation.
This means that in task-switching, even if the tasks are non-linguistic (in this case switching between colour and shape), bilinguals engage brain networks for language. Which is to say, bilinguals can recycle those brain structures that are highly specialized for language in monolinguals, and use them for cognitive control beyond the domain of language.
Speaking more than one language also changes the brain’s anatomy. Bilinguals have a greater density of white matter – bundles of neuronal projections – in the anterior cingulate than monolinguals do. And this effect doesn’t pertain only to those who learned more than one language during childhood. It is a characteristic that has been seen also in those who became bilingual later in life, and as such it might be particularly useful in old age, because the integrity of the connections is a decisive element in cognitive reserve. This explains why bilinguals, even when we factor in age, socioeconomic level and other relevant factors, are less prone to developing senile dementias.
To sum up, the study of bilingualism allows us to topple two myths: language development doesn’t slow down in bilingual children, and the same person can mix languages with no problem. What’s more, the effects of bilingualism may go above and beyond the domain of language, helping develop cognitive control. Bilingualism helps children to be captains of their own thought, pilots of their existence. This ability is decisive in their social inclusion, health and future. So perhaps we should promote bilingualism. Amidst so many less effective and more costly methods of stimulating cognitive development, this is a much simpler, beautiful and enduring way to do so.
A conjecturing machine (#ulink_07f2ce43-ef84-537b-a1ea-3cdf6544cb49)
Children, from a very young age, have a sophisticated mechanism for seeking out and building knowledge. We were all scientists in our childhood,
and not only out of a desire to explore, to break things apart to see how they work – or used to work – or to pester adults with an infinite number of questions beginning ‘Why?’ We were also little scientists because of the method we employed to discover the universe.
Science has the virtue of being able to construct theories based on scant, ambiguous data. From the paltry remnants of light from some dead stars, cosmologists were able to build an effective theory on the origin of the universe. Scientific procedure is especially effective when we know the precise experiment to discriminate between different theories. And kids are naturally gifted at this job.
A game with buttons (push buttons, keys or switches) and functions (lights, noise, movement) is like a small universe. As they play, children make interventions that allow them to reveal mysteries and discover the causal rules of that universe. Playing is discovering. In fact, the intensity of a child’s game depends on how much uncertainty the child has with regard to the rules that govern it. And when children don’t know how a simple machine works, they usually spontaneously play in the way that is most effective to discover its functioning mechanism. This is very similar to a precise aspect of the scientific method: investigation and methodical exploration in order to discover and clarify causal relationships in the universe.
But children’s natural exploration of science goes even further: they construct theories and models according to the most plausible explanation for the data they observe.
There are many examples of this, but the most elegant begins in 1988 with an experiment by Andrew Meltzoff – again – which produced the following scene. An actor enters a room and sits in front of a box with a large plastic button, pushes the button with their head and, as if the box were a slot machine paying out, there is a fanfare with colourful lights and sounds. Afterwards, a one-year-old baby who has been observing the scene is seated, on their mother’s lap, in front of the same machine. And then, spontaneously, the young child leans forward and presses the button with their head.
Did they simply imitate the actor or had the one-year-old discovered a causal relationship between the button and the lights? Deciding between these two possibilities would require a new experiment like the one proposed by the Hungarian psychologist György Gergely, fourteen years later. Meltzoff thought that the babies were imitating the actor when they pressed the button with their head. Gergely had another, much bolder and more interesting idea. The babies understand that the adult is intelligent and, because of that, if they didn’t push the button with their hand, which would be more natural, it was because pushing it with their head was strictly necessary.
This bold theory suggests that the reasoning of babies turns out to be much more sophisticated, and includes a theory of how things and people work. But how can one detect such reasoning in a child that doesn’t yet talk? Gergely solved it in a simple, elegant way. Imagine an analogous situation in everyday life. A person is walking with many bags and opens a door handle with an elbow. We all understand that door handles are not meant to be opened with your elbow and the person did that because there was no other option. What would happen if we replicated this idea in Meltzoff’s experiment? The same actor arrives, loaded down with bags, and pushes the button with their head. If the babies are simply imitating the actor, they would do the same. But if, on the other hand, they are capable of thinking logically, they will understand that the actor pushed it with their head because their hands were full and, therefore, all the babies needed to do to get the colourful lights and sounds was to push the button, with any part of their body.
They carried out the experiment. The baby observed the actor, laden with shopping bags, pushing the button with their head. Then the child sits on their mother’s lap and pushes the button with their hands. It is the same baby that, upon seeing the actor do the same thing but with their hands free, had pushed the button with their head.
One-year-olds construct theories on how things work based on what they observe. And among those observations is that of perceiving other people’s perspectives, working out how much they know, what they can and cannot do. In other words, exploring science.
The good, the bad and the ugly (#ulink_d152d2f8-8646-5ffe-be63-3f390e22f24c)
We began this chapter with the arguments of the empiricists, according to which all logical and abstract reasoning occurs after the acquisition of language. But nevertheless we saw that even newborns form abstract and sophisticated concepts, that they have notions of mathematics, and display some understanding of language. At just a few months old, they already exhibit a sophisticated logical reasoning. Now we will see that young children who do not yet speak have also forged moral notions, perhaps one of the fundamental pillars of human social interaction.
The infants’ ideas of what is good, bad, fair, property, theft and punishment – which are already quite well established – cannot be fluently expressed because their control tower (circuits in the prefrontal cortex) is immature. Hence, as occurs with numerical and linguistic concepts, the infants’ mental richness of moral notions is masked by their inability to express it.
One of the simplest and most striking scientific experiments to demonstrate babies’ moral judgements was done by Karen Wynn in a wooden puppet theatre with three characters: a triangle, a square and a circle. In the experiment, the triangle goes up a hill. Every once in a while it backs up only to later continue to ascend. This gives a vivid impression that the triangle has an intention (climbing to the very top) and is struggling to achieve it. Of course, the triangle doesn’t have real desires or intentions, but we spontaneously assign it beliefs and create narrative explanations of what we observe.
A square shows up in the middle of this scene and bumps into the triangle on purpose, sending it down the hill. Seen with the eyes of an adult, the square is clearly despicable. As the scene is replayed, the circumstances change. While the triangle is going up, a circle appears and pushes it upwards. To us the circle becomes noble, helpful and gentlemanly.
This conception of good circles and bad squares needs a narrative – which comes automatically and inevitably to adults – that, on the one hand, assigns intentions to each object and, on the other, morally judges each entity based on those intentions.
As humans, we assign intentions not only to other people but also to plants (‘sunflowers seek out the sun’), abstract social constructions (‘history will absolve me’ or ‘the market punishes investors’), theological entities (‘God willing’) and machines (‘damn washing machine’). This ability to theorize, to turn data into stories, is the seed of all fiction. That is why we can cry in front of a television set – it is strange to cry because something happens to some tiny pixels on a screen – or destroy blocks on an iPad as if we were in a trench on the Western Front during the First World War.
In Wynn’s puppet show there are only triangles, circles and squares, but we see them as someone struggling, a bad guy who hinders progress, and a do-gooder who helps. Which is to say that, as adults, we have an automatic tendency to assign moral values. Do six-month-olds have that same abstract thought process? Would babies be able spontaneously to form moral conjectures? We can’t know by asking because they don’t yet talk, but we can infer this narrative by observing their preferences. The constant secret of science consists, precisely, in finding a way of bridging what we want to know – in this case, whether babies form moral concepts – with what we can measure (which objects the babies choose).
After watching one object helping the triangle climb the hill and another bumping it down, infants were encouraged to reach for one of them. Twenty-six of twenty-eight (twelve out of twelve six-month-olds) chose the helper. Then, the video recordings of the infants watching the scenes of the helper and the hinderer were shown to an experimentalist. And, relying on their facial gestures and expressions alone, she could predict almost perfectly whether the infant had just seen the helper or the hinderer.
Six-month-old infants, before crawling, walking or talking, when they are barely discovering how to sit up and eat with a spoon, are already able to infer intentions, desires, kindness and evil, as can be deduced from examining their choices and gestures.
He who robs a thief … (#ulink_205f5ccc-8142-5c71-937d-92b764714de4)
The construction of morality is, of course, much more sophisticated. We cannot judge a person to be good or bad just by knowing they did something helpful. For example, helping a thief is usually considered ignoble. Would the babies prefer someone who helps a thief to someone who thwarts one? We are now in the murky waters that are the origins of morality and law. But even in this sea of confusion, babies between nine months and a year of age already have an established opinion.
