what you 're drawn to are her eyes and the skin you love to touch
but today i 'm going to talk to you about something you can 't see what 's going on up in that little brain of hers
the modern tools of neuroscience are demonstrating to us that what 's going on up there is nothing short of rocket science
and what we 're learning is going to shed some light on what the romantic writers and poets described as the celestial openness of the child 's mind
what we see here is a mother in india and she 's speaking koro which is a newly discovered language
and she 's talking to her baby what this mother and the eight hundred people who speak koro in the world understands is that to preserve this language they need to speak it to the babies and therein lies a critical puzzle
why is it that you can 't preserve a language by speaking to you and i to the adults well it 's got to do with your brain
what we see here is that language has a critical period for learning
work in my lab is focused on the first critical period in development and that is the period in which babies try to master which sounds are used in their language
we think by studying how the sounds are learned we 'll have a model for the rest of language and perhaps for critical periods that may exist in childhood for social emotional and cognitive development
a six monther adores the task
what have we learned well babies all over the world are what i like to describe as citizens of the world they can discriminate all the sounds of all languages no matter what country we 're testing and what language we 're using
and that 's remarkable because you and i can 't do that we 're culture bound listeners we can discriminate the sounds of our own language but not those of foreign languages so the question arises when do those citizens of the world turn into the language bound listeners that we are and the answer before their first birthdays
what you see here is performance on that head turn task for 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 something incredible occurs the babies in the united states are getting a lot better babies in japan are getting a lot worse but both of those groups of babies are preparing for exactly the language that they are going to learn
so the question is what 's happening during this critical two month period this is the critical period for sound development but what 's going on up there so there are two things going on
i
and those distributions grow and what we 've learned is that babies are sensitive to the statistics and the statistics of japanese and english are very very different
english has a lot of rs and ls the distribution shows and the distribution of japanese is totally different where we see a group of intermediate sounds which is known as the japanese r
so babies absorb the statistics of the language and it changes their brains it changes them from the citizens of the world to the culture bound listeners that we are
but we as adults are no longer absorbing those statistics we 're governed by the representations in memory that were formed early in development
so what we 're seeing here is changing our models of what the critical period is about we 're arguing from a mathematicalstandpoint that the learning of language material may slow down when our distributions stabilize it 's raising lots of questions about bilingual people
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 so we asked ourselves can the babies take statistics on a brand new language
and we tested this by exposing american babies who 'd never heard a second language to mandarin for the first time during the critical period
we knew that when monolinguals were tested in taipei and seattle on the mandarin sounds they showed the same pattern six to eight months they 're totallyequivalent two months later something incredible happens but the taiwanese babies are getting better
not the american babies what we did was expose american babies during this period to mandarin it was like having mandarin relatives come and visit for a month
so what have we done to their little brains
we had to run a control group to make sure that just coming into the laboratory didn 't improve your mandarin skills
so a group of babies came in and listened to english and we can see from the graph that exposure to english didn 't improve their mandarin but look at what happened to the babies exposed to mandarin for twelve sessions they were as good as the babies in taiwan who 'd been listening for ten and a half months
what it demonstrated is that babies take statistics on a new language whatever you put in front of them they 'll take statistics on
but we wondered what role the human being played in this learning exercise so we ran another group of babies in which the kids got the same dosage the same twelve 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 what did we do to their brains what you see here is the audio result no learningwhatsoever and the video result
no learningwhatsoever it takes a human being for babies to take their statistics
the social brain is controlling when the babies are taking 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 thankfully we have a new
using three hundred and six squids these are superconducting quantum interference devices to pick up the magnetic fields
babies in an meg machine while they are learning so this is little emma she 's a six monther and she 's listening to various languages in the earphones that are in her ears you can see she can
so she 's free to move completely unconstrained it 's a technical tour de force what are we seeing 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
and we 're going to be able to invent brain based interventions for children who have difficulty learning
just as the poets and writers described we 're going to be able to see i think that wondrous openness utter and complete openness of the mind of a child
in investigating the child 's brain we 're going to uncover deep truths about what it means to be human and in the process we may be able to help keep our own minds open to learning for our entire lives thank you
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