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Thursday, April 30, 2009

Jonah Lehrer - Inside the Baby Mind

Baby brains are amazing. As much as I never wanted children, it would be cool to have one I could study (which is why I should never be a parent). Jonah Lehrer offers some insight into what is going on inside those cute little heads (and it's a lot more than most of us ever thought).

Inside the baby mind

It's unfocused, random, and extremely good at what it does. How we can learn from a baby's brain.



By Jonah Lehrer April 26, 2009

WHAT IS IT like to be a baby? For centuries, this question would have seemed absurd: behind that adorable facade was a mostly empty head. A baby, after all, is missing most of the capabilities that define the human mind, such as language and the ability to reason. Rene Descartes argued that the young child was entirely bound by sensation, hopelessly trapped in the confusing rush of the here and now. A newborn, in this sense, is just a lump of need, a bundle of reflexes that can only eat and cry. To think like a baby is to not think at all.

Modern science has largely agreed, spending decades outlining all the things that babies couldn't do because their brains had yet to develop. They were unable to focus, delay gratification, or even express their desires. The Princeton philosopher Peter Singer famously suggested that "killing a disabled infant is not morally equivalent to killing a person. Very often it is not wrong at all."

Now, however, scientists have begun to dramatically revise their concept of a baby's mind. By using new research techniques and tools, they've revealed that the baby brain is abuzz with activity, capable of learning astonishing amounts of information in a relatively short time. Unlike the adult mind, which restricts itself to a narrow slice of reality, babies can take in a much wider spectrum of sensation - they are, in an important sense, more aware of the world than we are.

This hyperawareness comes with several benefits. For starters, it allows young children to figure out the world at an incredibly fast pace. Although babies are born utterly helpless, within a few years they've mastered everything from language - a toddler learns 10 new words every day - to complex motor skills such as walking. According to this new view of the baby brain, many of the mental traits that used to seem like developmental shortcomings, such as infants' inability to focus their attention, are actually crucial assets in the learning process.

In fact, in some situations it might actually be better for adults to regress into a newborn state of mind. While maturity has its perks, it can also inhibit creativity and lead people to fixate on the wrong facts. When we need to sort through a lot of seemingly irrelevant information or create something completely new, thinking like a baby is our best option.

"We've had this very misleading view of babies," says Alison Gopnik, a psychologist at the University of California, Berkeley, and author of the forthcoming book, "The Philosophical Baby." "The baby brain is perfectly designed for what it needs to do, which is learn about the world. There are times when having a fully developed brain can almost seem like an impediment."

One of the most surprising implications of this new research concerns baby consciousness, or what babies actually experience as they interact with the outside world. While scientists and doctors have traditionally assumed that babies are much less conscious than adults - this is why, until the 1970s, many infants underwent surgery without anesthesia - that view is being overturned. Gopnik argues that, in many respects, babies are more conscious than adults. She compares the experience of being a baby with that of watching a riveting movie, or being a tourist in a foreign city, where even the most mundane activities seem new and exciting. "For a baby, every day is like going to Paris for the first time," Gopnik says. "Just go for a walk with a 2-year-old. You'll quickly realize that they're seeing things you don't even notice."

There's something slightly paradoxical about trying to study the inner life of babies. For starters, you can't ask them questions. Young children can't describe their sensations or justify their emotions; they can't articulate the pleasure of a pacifier or explain the comfort of a stuffed animal. And, of course, none of us have any memories of infancy. For a scientist, the baby mind can seem like an impenetrable black box.

In recent years, however, scientists have developed new methods for entering the head of a baby. They've looked at the density of brain tissue, analyzed the development of neural connections, and tracked the eye movements of infants. By comparing the anatomy of the baby brain with the adult brain, scientists can make inferences about infant experience.

These new research techniques have uncovered several surprising findings. It turns out that the baby brain actually contains more brain cells, or neurons, than the adult brain: The instant we open our eyes, our neurons start the "pruning process," which involves the elimination of seemingly unnecessary neural connections. Furthermore, the distinct parts of the baby cortex - the center of sensation and higher thought - are better connected than the adult cortex, with more links between disparate regions. These anatomical differences aren't simply a sign of immaturity: They're an important tool that provides babies with the ability to assimilate vast amounts of information with ease.

While the pruning process makes the brain more efficient, it can also narrow our thoughts and make learning more difficult, as we become less able to adjust to new circumstances and absorb new ideas. In a sense, there's a direct trade-off between the mind's flexibility and its proficiency. As Gopnik notes, this helps explain why a young child can learn three languages at once but nevertheless struggle to tie his shoelaces.

But the newborn brain isn't just denser and more malleable: it's also constructed differently, with far fewer inhibitory neurotransmitters, which are the chemicals that prevent neurons from firing. This suggests that the infant mind is actually more crowded with fleeting thoughts and stray sensations than the adult mind. While adults automatically block out irrelevant information, such as the hum of an air conditioner or the conversation of nearby strangers, babies take everything in: their reality arrives without a filter. As a result, it typically takes significantly higher concentrations of anesthesia to render babies unconscious, since there's more cellular activity to silence.

The hyperabundance of thoughts in the baby brain also reflects profound differences in the ways adults and babies pay attention to the world. If attention works like a narrow spotlight in adults - a focused beam illuminating particular parts of reality - then in young kids it works more like a lantern, casting a diffuse radiance on their surroundings.

"We sometimes say that adults are better at paying attention than children," writes Gopnik. "But really we mean just the opposite. Adults are better at not paying attention. They're better at screening out everything else and restricting their consciousness to a single focus."

Consider, for instance, what happens when preschoolers are shown a photograph of someone - let's call her Jane - looking at a picture of a family. When the young children are asked questions about what Jane is paying attention to, the kids quickly agree that Jane is thinking about the people in the picture. But they also insist that she's thinking about the picture frame, and the wall behind the picture, and the chair lurking in her peripheral vision. In other words, they believe that Jane is attending to whatever she can see.

While this less focused form of attention makes it more difficult to stay on task - preschoolers are easily distracted - it also comes with certain advantages. In many circumstances, the lantern mode of attention can actually lead to improvements in memory, especially when it comes to recalling information that seemed incidental at the time.

Consider this memory task designed by John Hagen, a developmental psychologist at the University of Michigan. A child is given a deck of cards and shown two cards at a time. The child is told to remember the card on the right and to ignore the card on the left. Not surprisingly, older children and adults are much better at remembering the cards they were told to focus on, since they're able to direct their attention. However, young children are often better at remembering the cards on the left, which they were supposed to ignore. The lantern casts its light everywhere.

"Adults can follow directions and focus, and that's great," says John Colombo, a psychologist at the University of Kansas. "But children, it turns out, are much better at picking up on all the extraneous stuff that's going on. . . . And this makes sense: If you don't know how the world works, then how do you know what to focus on? You should try to take everything in."

While thinking like an adult is necessary when we need to focus, or when we already know which information is relevant, many situations aren't so clear-cut. In these instances, paying strict attention is actually a liability, since it leads us to neglect potentially important pieces of the puzzle. That's when it helps to think like a baby.

This new understanding of baby cognition, and the peculiar ways in which babies pay attention, is also giving scientists insights into improving the mental functioning of adults. The ability to direct attention, it turns out, doesn't merely inhibit irrelevant facts and perceptions - it can also stifle the imagination. Sometimes, the mind performs best when we don't try to control it.

The differences in how babies and adults pay attention are primarily caused by the unformed nature of the prefrontal cortex, a brain area just behind the eyes. While the prefrontal cortex has been greatly enlarged during human evolution - it's responsible for a wide variety of cognitive abilities, from directed attention to abstract thought - it's also the last brain area to fully develop, and often isn't done developing until late adolescence.

Although scientists have long held the lack of a functional prefrontal cortex responsible for all sorts of "childish" behaviors, researchers are beginning to realize that, sometimes, it might actually be better to allow the prefrontal cortex to loosen its grip.

A recent brain scanning experiment by researchers at Johns Hopkins University found that jazz musicians in the midst of improvisation - they were playing a specially designed keyboard in a brain scanner - showed dramatically reduced activity in the prefrontal cortex. It was only by "deactivating" this brain area that the musicians were able to spontaneously invent new melodies. The scientists compare this unwound state of mind with that of dreaming during REM sleep, meditation, and other creative pursuits, such as the composition of poetry. But it also resembles the thought process of a young child, albeit one with musical talent. Baudelaire was right: "Genius is nothing more nor less than childhood recovered at will."

The immaturity of the baby brain comes with another advantage: utter absorption in the moment. The best evidence for this comes from brain scans of adult subjects as they watched an engrossing Clint Eastwood movie. The experiment, led by Rafael Malach at Hebrew University, found that when adults were watching the film their brains showed a peculiar pattern of activity, as their prefrontal areas were suppressed. At the same time, areas in the back of the brain associated with visual perception were turned on. As Gopnik notes, this mental state - the experience of being captivated by entertainment - is, in many respects, a fleeting reminder of what it feels like to be a young child. "You are incredibly aware of what's happening - your experiences are very vivid - and yet you're not self-conscious at all," she says. "You're not thinking about anything but what's on the screen."

But it's not just the movie theater that transports us back to a newborn state of mind, in which we're fully immersed in the moment. Gopnik notes that a number of other situations, from Zen meditation to the experience of natural beauty, can also lead to states of awareness so intense that the self seems to disappear. "This is the same ecstatic feeling that the Romantic poets were always writing about," she says. "It's seeing the world in a grain of sand."

If people could never regress into this babylike consciousness, then we'd struggle with the kind of tasks that require us to stop being self-conscious and lose ourselves in the job. Such moments are often described as "flow" activities, and can occur whenever we're completely captivated by what we're doing, be it stirring a risotto or solving a crossword puzzle. The Zen Master Shunryu Suzuki referred to such modes as "beginner's mind," since people are able to think like a baby, open to possibility and free of errant preconceptions.

Gopnik has discovered for herself the advantages of being able to shift between a babyesque form of cognition and a more adult frame of mind. "As a scientist, you really need to use both kinds of thinking," she says. "Sometimes you need to focus and analyze your data. But you also need the ability to be open and creative, to think in a new way if the old way isn't working."

At such moments, she suggests, we need to think with the innocence of an infant - to release the reins of attention and look anew at a world we're still trying to understand.

Jonah Lehrer is the author of "How We Decide" and "Proust Was a Neuroscientist." He is a regular contributor to Ideas.

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