Patricia Kuhl
Patricia Kuhl talk about
the little brain of babies that we cannot see. The modern tools of neuroscience are
demonstrating to us that what's going on up there is nothing short of
rocket science.
A mother in India is talking to her
baby with Koro language, which is a newly discovered language. To preserve this language, they need to speak it to the babies. Language has a
critical period for learning, the babies and children are geniuses until they
turn seven on
learning a second language. After puberty,
we fall off the map.
Work in my lab is focused
on the first critical period in development where babies try to master which sounds are used in their
language. So we've been studying the babies using a technique that we're using all over the
world and the sounds of all languages. The baby sits on a parent's lap, and we train them to turn their heads when a
sound changes like from "ah" to "ee." If they do so at the appropriate time, the black
box lights up and a panda bear pounds a
drum. A six-monther adores the task.
Babies all over the world are describe as citizen of the world, because hey can
discriminate all the sounds of all languages. We're culture-bound
listeners. We only can
discriminate the sounds of our own language. Before their first
birthdays, those citizens
of the world turn into the language-bound listeners. Babies tested in Tokyo and the United States, here in Seattle, as they listened to "ra" and
"la" sounds important to English, but not to Japanese. So at six to eight months, the babies are totally
equivalent. Two months later, The babies in the United States are getting a lot
better, babies in Japan are getting a lot worse, but both are preparing for exactly the language that they are going to learn.
here are two things happening
during this critical two-month period. First: babies are
listening intently to us, and they're taking
statistics as they listen to us talk. There are two mothers
speaking motherese the universal language we use when we talk to
kids, first in English and then in Japanese.
Babies taking statistics on the language that they hear. The statistics of Japanese and English are very different. English has a
lot of Rs and Ls. The distribution of Japanese is totally
different, babies absorb
the statistics of the language and it changes their brains.
We're arguing from a
mathematical standpoint that the learning of language material may slow
down when our distributions stabilize. Bilinguals must keep two sets of statistics in
mind at once and flip between them, one after the
other,depending on who they're speaking to.
We tested babies by exposing American babies who'd never heard a second language to Mandarin for the first time during the
critical period. What we did was expose American babies, during
this period, to Mandarin. It was like having Mandarin relatives come and
visit for a month and move into your house and talk to the babies
for 12 sessions. Here's what it looked like in the laboratory.
exposure to English didn't improve their Mandarin. But look at what happened
to the babies exposed to Mandarin for 12 sessions. They were as good as the babies in Taiwan who'd been listening for 10 and a half months. it demonstrated is that babies take
statistics on a new language.
because of our
curiousity the role of human being. Then we ran to another group of babies in
which the kids that also got 12 sessions, but over a television set. And another group of babies who had just audio
exposure and looked at a teddy bear on the screen. Only audio results no learning, only video
results no learning whatsoever. It takes a human being
for babies to take their statistics.
We want to get inside the brain and see this thing happening as
babies are in front of televisions, as opposed to in front of human beings with magnetoencephalography
machine. It looks like a hair
dryer from Mars. But it's completely safe, completely noninvasive
and silent. We're looking at millimeter accuracy with regard to spatial and millisecond accuracy using 306 SQUIDs these are superconducting quantum interference
devices to pick up the magnetic fields that change as we do our thinking.
little Emma, a six monther. She's listening to various
languages in the earphones that are in her ears. We're tracking her head with little pellets in a
cap, so she's free to move completely unconstrained. We're seeing the baby brain. As the baby hears a word in her language, the
auditory areas light up, and then subsequently areas surrounding it that
we think are related to coherence, getting the brain coordinated with its different
areas, and causality, one brain area causing another to activate.
We're going to be able to
see a child's brain as they experience an emotion, as they learn to
speak and read, as they solve a math problem, as they have an
idea. And we're going to be able to invent brain-based
interventions for children who have difficulty learning. we may be able to help keep our own minds open to
learning for our entire lives.
Komentar
Posting Komentar