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At the world's leading baby brain research lab at Harvard University, Elizabeth Spelke's team is conducting experiments that reveal not only that humans are born with a range of innate skills, but that our prejudices are formed within the first few months of life. By Roger Highfield
The lift doors open and Belinda Burnett carries her baby, Freya, into a bright and welcoming lobby, carpeted in maroon with walls of custard yellow and midnight blue. Playthings are scattered about - a magnet board, basketball hoop and bins of toys. There's all the hubbub of a typical nursery, a blend of sing-song 'motherese', the tinkle of toddler talk and lots of baby babble. Nearby, a member of staff coos as a little boy plonks a plastic arm between the eyes of Mr Potato Head. Behind the glass wall of an office stuffed animals gaze out, prizes for taking part in what are euphemistically called 'games'.
Belinda, 32, and her seven-month-old have just driven in from Somerville, north of Boston, so that her daughter's brain can be subjected to a series of experiments. Her husband is a mathematician at a nearby university, and she knows how difficult it can be for scientific researchers to find willing guinea pigs. This is Freya's third visit. 'She is a curious baby and enjoys being out and about,' Belinda, an Australian-born computer trainer, says. 'She likes meeting people and looking at different things. And I love finding out why babies do certain things.'
Welcome to Spelkeland, or, to give it its proper name, the Laboratory for Developmental Studies at Harvard University's Department of Psychology, run by the cognitive psychologist Prof Elizabeth Spelke, which is dedicated to understanding what shapes the most powerful known learning machine - the infant mind. Great philosophers have mused for millennia about human consciousness and how it makes sense of its surroundings. Like any good scientist, Spelke has turned philosophical hot air into firm experimental data that suggests that we are born with a significant amount of 'core knowledge' hardwired into our brains.
Spelke is arguably the most influential figure in the relatively new field of baby brain research, and has been named by Time magazine as one of America's best in a list of 'brilliant researchers who are the envy of the world'. One prominent British experimental psychologist, Prof Bruce Hood of the University of Bristol, says she has 'revolutionised infancy mind research'. The psychologist and writer Steven Pinker, Spelke's colleague at Harvard, is another who acknowledges her profound impact, and says her ingenuity has shown that 'babies are smarter than we thought'.
The hub of Spelke's empire occupies half of the 11th floor of William James Hall, a brutalist 1960s tower block named after the pioneering American psychologist. James himself once referred to the 'blooming, buzzing confusion' of a newborn's senses. Spelke's studies have revealed that, in fact, there is order in the chaos: from the moment we first open our eyes, we possess the essential mental equipment to make sense of the confusion around us.
We are natural-born mathematicians - for example, six-month-olds can distinguish the quantities eight from 16, and 16 from 32. Babies will infer that a rolling ball will keep moving. They also know that when that ball rolls behind a screen it should pop out the other side. And although they can only babble, babies tell us that the germ of our instincts about age, gender and race are laid down in the cradle.
But how can you ask burbling babies what they are thinking? They are much trickier to handle than rats and students, the usual mainstays of psychological research. None the less, the Spelkeland experiments are fundamentally simple, and rely on the one thing that humans of any age can do: get bored. In a typical experiment, a baby is positioned in front of a large television screen in a darkened room. The screen then provides a stimulus, whether it is shapes, sounds, numbers or faces, and repeats the stimulus again and again until the baby tires (scientists refer to this as 'habituation').
It was Robert Fantz, an enterprising psychologist at Case Western Reserve University in Ohio, who in the 1950s found that babies, just like adults, get bored when they look at the same thing over and over again, but gaze more intently when they see something that confounds their expectations or that doesn't make sense, such as when endless images of regular rabbits are followed by a four-eared variety. Or if a wind-up toy moves under its own power, rather than with the help of a human hand.
Since then, psychologists have exploited infants' low boredom thresholds to probe their minds. Spelkeland, custom-built for the purpose, has hosted some of the most elaborate, elegant and productive experiments on object and facial recognition, motion, spatial navigation and numerosity (a rough grasp of numerical relationships).
Freya is sitting in front of a screen, taking part in a variant of the following experiment. An image of four dots appears, then disappears. Then another four dots flash up. Next, 16 dots appear on screen. You and I would think, 'Hang on a moment, shouldn't that be four-plus-four-equals-eight dots, not 16?' Remarkably, Freya seems to think something isn't quite right, too, and stares a bit longer, just to make sure. Next door, in the 'coding room', a couple of graduate students are poring over live and taped video to monitor her reaction.
Much of the lab's research on maturing brains has revealed that we are born with an innate number sense (despite the protestations of those who claim to be hopeless at mathematics). One of Spelke's researchers, Dr Koleen McCrink, has put about 700 babies through their paces over six years, at both Yale and Spelkeland. 'My bread and butter is looking at infants' ability to do mathematical operations,' she explains. She has found that even at six months a baby 'can add and subtract, and can also understand something about ratio'.
Her conclusion supports the Spelke line. 'We have got core systems for understanding the world,' which are not shaped by learning. What is striking, McCrink says, is how formal mathematics is such a slog. 'Babies can do all this complicated stuff, and yet it takes years to teach kids how to add and subtract precisely. It is so frustrating.'
The experiments may be straightforward, but no one ever said that working with infants is easy. The youngest babies have a wandering gaze, so the team tries to complete each experiment within 10 minutes. Even then, the infants often lurch backwards to look up at mum or dad; they will pull off a sock, fiddle with a button, or simply fall asleep. 'That can be a little insulting,' jokes another staff member, Gaye Soley, a 25-year-old graduate student.
Special tools are required to penetrate deeper into the baby brain. For the youngest, whose gazes wander endlessly, 'smart' dummies wired to a computer help Spelke's researchers measure their levels of excitement - a lot of sucking means a lot of interest. Far more complex are the sensor nets now in routine use at several baby labs. The ones in Spelkeland are dotted with 128 electrodes that pick up the crackles of electrical activity on the baby's scalp and pinpoint which parts of Freya's brain are in use when she is making sense of the number patterns on screen.
Dan Hyde, a 28-year-old graduate student, whisks a sensor net out of a beaker of salty water, which enables a good connection between sensors and skin. 'This will help explain at a deeper level what is going on,' he says. He then keeps Freya distracted while he anxiously drapes the floppy wet net on to her warm downy scalp. The cold net can sometimes trigger what the staff here call a 'fuss out' (tantrum) and spoil the experiment. Freya smiles, oblivious.
Hyde shows me a series of flickering lines on a nearby computer screen that trace out activity ('evoked response potentials') picked up by the sensors now dotting Freya's head. Some of the squiggles result from nerve signals sent to the muscles as she moves her head. Much more interesting are those from 'synchronised brain activity', revealing changes over as little as a thousandth of a second.
Elsewhere, in a lab in nearby Harvard Medical School, Hyde is developing a way to probe deeper still by passing an invisible infrared laser beam through a baby's head (quite harmless, he insists) to measure surges of blood flow when parts of the brain work harder. 'We get some good signals,' he says.
To find willing subjects, the mostly female team visits the four local town halls every two months to collect information from birth records. Through letters, web pages and flyers, the team asks anyone and everyone. Although there is no attempt to select the babies by intellect, this part of the United States is a powerhouse of research, and many babies, such as Freya, are the offspring of eggheads from MIT, Harvard, Tufts and other nearby academic institutions.
In all, many hundreds of babies take part each year in the effort, which is funded by mostly US Government grants. The parents are paid $5 to cover travel expenses; the children are given a toy or T-shirt for their trouble. Freya ends up with a duck. The motivations of the mums and dads are mixed; for some, it is simply curiosity about how their baby is developing; for others, it is a genuine interest in helping the cause of science; others say they are simply happy to have a change of scene. They can hang out in the lobby all day if they want to.
T-shirts from rival baby labs hang on the wall of the lobby like trophies. The logos of research teams in Munich, Carnegie Mellon, Berkeley, Cardiff and about 20 others reveal the extraordinary flowering of baby research in recent years. Of them all, Spelkeland is the most influential. Spelke's empire was born in 1977 and, after touring MIT, Cornell and the University of Pennsylvania, she settled in Harvard. Her office is the traditional academic clutter of books and papers, though there are some incongruous touches. An inflatable palm tree slumps in one corner ('it needs a little more air').
One crowded shelf has been invaded by wind-up toys. These hoppers, walkers and waddlers were once used to engage the interest of the children, to help study how they categorise animals, and so on. Lab members still like to swell her collection. There is even a wind-up brain, though, Spelke explains, 'That is for my benefit only, not for the children.' She has two grown-up children of her own, Bridget and Joe.
Spelke leans forward and talks with an open, earnest smile and expansive hand movements - the same technique she uses when engaging with toddlers. A tall bespectacled figure, her quest to probe the infant mind began when she was an undergraduate at Harvard in the 1960s, working under Jerome Kagan, an iconoclast in the field of developmental psychology. 'In order to understand anything about infants, social relationships and their emotional reactions, we needed to understand what they could perceive and what they could understand about other people and things,' she says. 'That sent me on a long detour.' Now 58, she is still seeking answers.
When Spelke's research began, the dominant thinking was that of the influential Swiss developmental psychologist Jean Piaget who, after keeping meticulous diaries of the behaviour of his own three children in the 1930s, believed that babies were not empty vessels to be filled but little boffins primed to devour and exploit any and every experience. Even so, doctors of that time thought that babies had such a diminished consciousness they had no sense of pain, so did not need anaesthetic if undergoing surgery.
Part of this belief was pragmatic - in the 1940s and 1950s, when doctors lacked the means to administer precise doses of anaesthetic and monitor vital functions, babies often died from overdoses. Instead of anaesthesia, doctors gave babies muscle relaxants to paralyse them. They looked comfortable and could not scream or cry. Thinking changed when a comprehensive review published by a Harvard team in the 1980s revealed how infants' stress hormones soared after surgery (today a similar debate rages about the age at which a foetus can feel pain).
Even 30 years ago babies were thought to be blind at birth, too. One simple observation in 1983 showed that this was a misconception. The American psychologist Andy Meltzoff stuck his tongue out at a 42-minute-old newborn. He and his peers were astounded to see the tongue of the freshly washed baby poke out in response. (Babies, we now know, are not blind but short-sighted - they see far enough to spot a nipple and their mother's face - so you have to get pretty close to provoke a response.)
It is not hard to see why the psychologists were startled. Newborns have no idea what they look like, yet they enter the world equipped with a basic understand of what a face is. They know that the pink blob in the middle of a face is a tongue, and that they can poke out their own tiny tongue in just the same way. This was crucial ammunition for an intellectual war that still rages over whether we emerge from the womb as general-purpose learning machines that soak up details of our environments, or, as Spelke believes, born 'precocious', so we can immediately do things that are key to survival (just as newly-hatched chicks and fish can immediately do things such as navigate, or find and recognise food).
Spelke has crossed swords with Professor Mark Johnson of Birkbeck's Centre for Brain and Cognitive Development in London, whose studies of infant brains stretch back nearly two decades. He points out that the four and six month olds at Spelkeland have hundreds of hours of experience in categorising the world, which challenges Spelke's 'core knowledge' theory. He believes that we enter the world with 'soft biases to attend to different aspects of the environment, and to learn about the world in particular ways'.
His colleague, Prof Annette Karmiloff-Smith, who once worked with Piaget, praises some of the Spelkeland work ('Liz has done some great behavioural experiments') but adds, 'Paradoxically, although she studies babies, in my view she doesn't raise questions about infants' capacity for learning, which may account for their extraordinary abilities without the need for them to be born with pre-specified knowledge.'
One area into which Spelke's team would like to delve deeper is the origins of bigotry in human beings. In the case of skin colour, newborns respond to individuals of all races equally. By three months, however, a baby from a Caucasian household will prefer to gaze at a white face, and a black baby at an African American face. By the age of two or three, they are drawn to their own gender, too. 'There are some very intriguing parallels between the patterns of social preference we find in infants and what seems to go on in adults,' Spelke says. 'But we don't have them nailed. It is the work I will get most animated about, but the reason I am so animated is that we don't have the answers yet.' The effort to find how babies divide people into broad groups began only five years ago, 'a blink of an eye' in research terms.
Spelke's studies found baby boys and girls have similar mathematical ability, an incidental finding that was at the forefront of her mind in January 2005 when the former Harvard president Larry Summers suggested that the relative lack of female engineers and scientists was down to innate gender differences. 'When it comes to the basic modules we are born with, they are pretty much the same,' says Spelke, who was in the thick of the verbal fisticuffs that followed (Summers was 'wrong, point for point'). Summers resigned as controversy raged. Spelke does not deny that there are differences in the way men and women think but most of this, she believes, is learnt over time, and down to prejudice and the expectations of society.
Among some scientists there is a reluctance to ask questions about skin colour, so ingrained is the fear that conclusions will be exploited for political ends, or distorted by doublethink. Spelke is fearless. 'The trouble is there, whether we do our research or not. Knowledge is liberating.' The more we understand the foundations of how we think, 'the more effectively we will be able to move in the directions we choose to go in. I am not so worried the research would be misused.'
Studies have already revealed why some old people mutter that all Chinese or Westerners look the same, depending on whether they are Western or Chinese. Six-month-olds are much better than us at discriminating faces of other races and can even tell individual monkeys apart. But that capacity evaporates at nine months, when they tune this skill to discriminate only faces of their own race.
Talee Ziv, another graduate student, is at Spelkeland to follow up some remarkable experiments she did at Tel Aviv University, Israel, with children from care homes. 'The question was very simple,' Ziv says. 'We wanted to know whether children who are three months old have a certain preference for faces of certain races.'
Three groups of 12 babies took part: white Israeli children who had probably been exposed only to white faces; their peers in Ethiopia who probably had no exposure to white faces; and Ethiopian babies exposed to black and white faces because their families had emigrated to Israel. 'We presented them with pictures of faces, side by side, one white and one African, and we observed where they preferred to look. The white children in Israel preferred white faces. Babies in Ethiopia preferred to look at Ethiopian faces. The third group showed no preference.'
More fascinating still is that Spelke's lab has revealed a deep-seated prejudice, present in infants, that trumps racial bias: language. Dr Katherine Kinzler, though based in Harvard, spends much time running parallel studies in France. 'Five-month-old babies will look longer at somebody who spoke to them in their language. Older infants want to accept a toy from someone who has spoken their language,' Dr Kinzler says.
'They like toys more that are associated with someone who has spoken their language. They prefer to eat foods offered to them by a native speaker compared to a speaker of a foreign language. And older children say that they want to be friends with someone who speaks in their native accent.' Accents and vernacular, far more than race, seem to influence the people we like. 'Children would rather be friends with someone who is from a different race and speaks with a native accent versus somebody who is their own race but speaks with a foreign accent.'
These findings make perfect sense according to two California-based pioneers of evolutionary psychology, John Tooby and Leda Cosmides. In the Stone Age, race was next to useless as an identifier, because most people would never have travelled far enough to see anyone of a different skin colour. Accent, vocabulary and dialect would have helped distinguish friendly tribes from foes. Tooby and Cosmides concluded that humans are born with a predisposition to divide the world along ethnic lines traced out by language and accent, more than racial lines.
Does Spelke think her research can help reduce prejudice? 'That is a very difficult question and probably a premature one since we have a great deal more to learn.' But her hope is that the better we understand our predispositions, the more chance society has to deal with hate and bigotry.
In the lobby, I find an unlikely advocate in the guise of the Rev Hank Peirce ('the old Yankee spelling'), who is on his day off from his Unitarian ministry a few miles away in Medford. He has brought along baby Bethiah to 'play a game' with the lab's energetic manager, Kate Ellison. This is not his first time. He has taken his three-year-old, Ruth, to Spelkeland, too, some six times since the age of three months. 'It's a lot of fun,' he says, explaining how she has done experiments with Talee Ziv on race, among others. He tells me the research is crucial because children have been relatively understudied by medicine, a shortcoming now being rectified.
'Learning how children think and develop is so important to help us figure out how we all learn and to avoid bias and stereotypes,' he says, with a passion I suspect he usually reserves for the pulpit. His smiling six-month-old gets lots of attention. 'Bethiah, good job!' Ellison cries, after the experiments to see how the baby responds to images of faces from different races.
Bethiah leaves Spelkeland proudly clutching a new T-shirt bearing the lab's logo, blissfully unaware that her tiny mind is helping some of the biggest brains in America reveal the roots of human behaviour.
First published in The Telegraph.
To understand how to interpret the cries of your newborn, see Baby etc's Dunstan Baby Language DVD.
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