Saturday, August 15, 2009

Babies' brains are more sophisticated than we ever believed

A baby’s mind is quite brilliant, a psychologist says in her new book. Far from being irrational, children are more astute than many adults

Alison Gopnik

In the past 30 years we’ve learnt more about babies and young children than in the preceding 2,500 years and that has given us new ideas about human nature itself — about knowledge and imagination, truth and consciousness. Thirty years ago most psychologists and philosophers thought that babies and young children were basically defective adults — irrational and egocentric, unable to think logically, take another person’s perspective or reason causally.

If you just looked cursorily at babies and young children, as generations of philosophers did, you might well conclude that there was not much going on. If you looked carefully, as generations of mothers and the great psychologist Jean Piaget did, you would start to appreciate how philosophically significant, fascinating and profound children are.

It is this sophistication that I hope to reveal in my book, The Philosophical Baby. For those of us who are intrigued but, equally, sometimes frustrated by a baby’s apparent lack of reason or awareness of the outside world, I hope that the latest ground-breaking research will explain just how brilliant a baby’s mind really is. Neither mothers nor even Piaget had the recording tools and experimental techniques that we have now that show babies and young children know much more than we ever believed.

One reaction to this research has been to say that all that knowledge must be built into our genes and that, therefore, experience and learning play only a small part.But studies show that this is not the case. Far from being irrational and illogical, in some ways children are brighter than adults. Even the youngest children turn out to have remarkably sophisticated and powerful learning abilities.

This was evident in three very recent experiments. First Professor Fei Xu, of the Department of Psychology at the University of California, Berkeley, took a group of one-year-old babies and showed them a box full of mixed-up ping-pong balls — 80 per cent white and 20 per cent red. The babies were more surprised, and looked more intently at the researcher when she pulled four red balls in a row out of the box, a statistically unlikely though possible event, than when she pulled out four white balls. The babies concluded that the researcher must like the red balls more than the white ones as when she held out her hand, they gave her a red ball rather than a white one. Far from being illogical and egocentric they could learn from statistics and use the logic of what they saw to figure out what someone else wanted.

In a second experiment, Laura Schulz, assistant professor of Cognitive Sciences at the Massachusetts Institute of Technology, showed that when young children play they are really experimenting with cause and effect. Pre-schoolers saw a toy with two levers and a duck that popped up on top. One group saw that when you pressed one lever the duck appeared, and when you pressed the other it didn’t. The second group saw that when you pressed both levers at once, the duck popped up, but they never got a chance to see what the levers did separately. This left the causal relation between the levers and the duck a mystery. When given the toy to play with, the children spontaneously played more with the puzzling toy and figured out how it worked. Schulz’s research suggests that when babies and young children are “into everything” they are really exploring and discovering.

In my own laboratory at Berkeley’s Institute of Human Development, my colleague Tamar Kushnir and I discovered that pre-schoolers can use probabilities to learn how things work. We showed them two blocks that were likely, but not certain, to make a box light up. These children, who couldn’t yet add or subtract, were more likely to try a block themselves when it made the machine light up two out of four times than when it only made it work two out of six times. All these experiments show an astonishing capacity for statistical reasoning, experimental discovery and logic beyond the knowledge babies are born with.

Although young children have remarkable learning abilities, they have even more remarkable imaginative abilities. Even great psychologists such as Piaget thought that young children were confused about the difference between reality and fantasy, hardly surprising for anyone who has walked into a nursery full of imaginary princesses and superheroes who politely serve you non-existent tea and ward off non-existent monsters. But new studies show that children actually understand the difference between reality and fantasy very well, they just think the imaginary world is more interesting than the real one.

The new research also shows that imagination and learning are closely linked. For example, consider imaginary friends. The psychologist Marjorie Taylor found that most pre-schoolers have had an imaginary companion at one time or another. Moreover, although the children loved to talk about, and with, their imaginary friends they knew quite well that they were non-existent. Taylor discovered that imaginary friends, and pretend play in general, help children to understand the people around them. Children who pretended a lot were better at understanding how other people’s minds worked.

So imagining peculiar people isn’t a sign that children are confused, it’s a sign that they’re clever.

Just as Einstein imagined different ways in which the world might be, so these little scientists are trying to imagine all the ways in which the people around them might be. For example, my own niece grew up in literary Manhattan and she had an imaginary friend who was too busy to play with her. She would bump into Charlie Ravioli at a coffee shop but he would have to run, and she would leave wistful messages on his imaginary answering machine. She was using her imagination to explore the folk ways of busy Manhattan city life.

The reason for many of these abilities is that the young brain is remarkably flexible and, as the neuroscientists say, “plastic”, with many more neural connections than the adult brain. It is awash in chemicals that make neurons especially good at learning. The disadvantage is that it is much less efficient. A baby’s brain is like a map of old Paris with many small winding streets. Over time, we prune away the connections we don’t use and the connections we do use become faster and more automatic. In the adult brain, these winding pathways are replaced by fewer, but more efficient, broad neural boulevards.

In fact, many scientists have started to think of the baby brain as an exceptionally powerful kind of computer. Developmental psychologists, myself included, are collaborating with computer scientists who design machines that can use statistics and probabilities to learn and imagine. Many of these systems use something called Bayesian learning, and we think that babies may be doing something similar. One of the best ways for a system to learn, whether it’s a computer, a brain or a baby, is to start out by imagining and exploring many different possibilities. As you gather more evidence you should start to believe that some of these possibilities are more and more likely to be true. Quite rationally, once you’re pretty sure you’re right, your strategy should be to make decisions based on that knowledge, and to become increasingly reluctant to give those ideas up and try something new.

Understanding those incredibly powerful learning machines may even tell us something about a baby’s consciousness. What is it like to be a baby? I think babies may be more conscious than we are. At the least, they are conscious of more than we are. Adult consciousness is often compared with a spotlight, beaming in on just the relevant parts of the world around us. But baby consciousness is more akin to a lantern, illuminating everything.

These remarkable results lead many parents to think that they need programmes and products to make their babies smarter, and there are millions of pounds to be made by exploiting parents’ ambitions for their children. Like the equally popular dieting books, though, the very profusion of parenting books should make you question their efficiency. In fact, the message of the research is just the opposite. We don’t need to make babies brighter because they are already as intelligent as they can be. Instead, we need to give them rich surroundings that they can explore. But those surroundings may be rich with simple things, cardboard boxes and mixing bowls, bean plants and goldfish. And the new research shows that, above all, babies are learning about, and from, the people who surround them. It’s ironic that as a society we spend millions on useless “educational” enhancements for babies but very little to support the carers who actually make a difference.

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