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The linguistic genius of babies | Patricia Kuhl | TEDxRainier

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    I want you to take a look at this baby.
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    What you're drawn to are her eyes
    and the skin you love to touch.
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    But today I'm going to talk to you
    about something you can't see.
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    What's going on
    up in that little brain of hers.
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    The modern tools of neuroscience
    are demonstrating to us
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    that what's going on up there
    is nothing short of rocket science.
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    And what we're learning
    is going to shed some light
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    on what the romantic writers and poets
    described as the "celestial openness"
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    of the child's mind.
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    What we see here is a mother in India,
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    and she's speaking Koro,
    which is a newly discovered language.
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    And she's talking to her baby.
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    What this mother --
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    and the 800 people who speak
    Koro in the world --
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    understands is that,
    to preserve this language,
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    they need to speak it to the babies.
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    And therein lies a critical puzzle.
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    Why is it that you can't
    preserve a language
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    by speaking to you and I, to the adults?
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    Well, it's got to do with your brain.
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    What we see here is that language
    has a critical period for learning.
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    The way to read this slide is to look
    at your age on the horizontal axis.
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    (Laughter)
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    And you'll see on the vertical
    your skill at acquiring a second language.
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    The babies and children are geniuses
    until they turn seven,
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    and then there's a systematic decline.
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    After puberty, we fall off the map.
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    No scientists dispute this curve,
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    but laboratories all over the world
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    are trying to figure out
    why it works this way.
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    Work in my lab is focused on the first
    critical period in development,
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    and that is the period in which babies
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    try to master which sounds
    are used in their language.
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    We think, by studying
    how the sounds are learned,
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    we'll have a model
    for the rest of language,
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    and perhaps for critical periods
    that may exist in childhood
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    for social, emotional
    and cognitive development.
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    So we've been studying the babies
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    using a technique
    that we're using all over the world
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    and the sounds of all languages.
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    The baby sits on a parent's lap,
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    and we train them to turn
    their heads when a sound changes --
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    like from "ah" to "ee."
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    If they do so at the appropriate time,
    the black box lights up
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    and a panda bear pounds a drum.
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    A six-monther adores the task.
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    What have we learned?
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    Well, babies all over the world
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    are what I like to describe
    as "citizens of the world."
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    They can discriminate
    all the sounds of all languages,
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    no matter what country we're testing
    and what language we're using,
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    and that's remarkable
    because you and I can't do that.
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    We're culture-bound listeners.
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    We can discriminate the sounds
    of our own language,
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    but not those of foreign languages.
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    So the question arises:
    When do those citizens of the world
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    turn into the language-bound
    listeners that we are?
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    And the answer:
    before their first birthdays.
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    What you see here is performance
    on that head-turn task
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    for babies tested in Tokyo
    and the United States,
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    here in Seattle,
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    as they listened to "ra" and "la" --
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    sounds important to English,
    but not to Japanese.
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    So at six to eight months,
    the babies are totally equivalent.
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    Two months later,
    something incredible occurs.
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    The babies in the United States
    are getting a lot better,
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    babies in Japan are getting a lot worse,
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    but both of those groups of babies
    are preparing for exactly the language
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    that they are going to learn.
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    So the question is: What's happening
    during this critical two-month period?
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    This is the critical period
    for sound development,
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    but what's going on up there?
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    So there are two things going on.
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    The first is that the babies
    are listening intently to us,
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    and they're taking statistics
    as they listen to us talk --
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    they're taking statistics.
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    So listen to two mothers
    speaking motherese --
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    the universal language
    we use when we talk to kids --
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    first in English and then in Japanese.
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    (Video) Ah, I love your big blue eyes --
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    so pretty and nice.
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    (Japanese)
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    Patricia Kuhl: So, what I'm telling you
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    is that during the production
    of speech, when babies listen,
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    what they're doing is taking statistics
    on the language that they hear.
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    And those distributions grow.
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    And what we've learned is that babies
    are sensitive to the statistics,
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    and the statistics of Japanese
    and English are very, very different.
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    English has a lot of Rs and Ls.
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    The distribution shows.
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    And the distribution of Japanese
    is totally different,
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    where we see a group
    of intermediate sounds,
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    which is known as the Japanese "R."
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    So babies absorb
    the statistics of the language
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    and it changes their brains;
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    it changes them
    from the citizens of the world
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    to the culture-bound
    listeners that we are.
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    But we as adults are no longer
    absorbing those statistics.
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    We are governed
    by the representations in memory
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    that were formed early in development.
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    So what we're seeing here
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    is changing our models
    of what the critical period is about.
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    We're arguing from
    a mathematical standpoint
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    that the learning of language
    material may slow down
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    when our distributions stabilize.
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    It's raising lots of questions
    about bilingual people.
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    Bilinguals must keep two sets
    of statistics in mind at once
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    and flip between them,
    one after the other,
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    depending on who they're speaking to.
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    So we asked ourselves,
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    can the babies take statistics
    on a brand new language?
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    And we tested this
    by exposing American babies
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    who'd never heard a second language
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    to Mandarin for the first time
    during the critical period.
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    We knew that, when monolinguals
    were tested in Taipei and Seattle
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    on the Mandarin sounds,
    they showed the same pattern.
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    Six to eight months,
    they're totally equivalent.
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    Two months later,
    something incredible happens.
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    But the Taiwanese babies are getting
    better, not the American babies.
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    What we did was expose American babies,
    during this period, to Mandarin.
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    It was like having Mandarin relatives
    come and visit for a month
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    and move into your house
    and talk to the babies for 12 sessions.
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    Here's what it looked like
    in the laboratory.
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    (Mandarin)
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    PK: So what have we done
    to their little brains?
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    (Laughter)
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    We had to run a control group to make sure
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    that coming into the laboratory
    didn't improve your Mandarin skills.
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    So a group of babies came in
    and listened to English.
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    And we can see from the graph
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    that exposure to English
    didn't improve their Mandarin.
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    But look at what happened to the babies
    exposed to Mandarin for 12 sessions.
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    They were as good as the babies in Taiwan
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    who'd been listening
    for 10 and a half months.
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    What it demonstrated is that babies
    take statistics on a new language.
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    Whatever you put in front of them,
    they'll take statistics on.
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    But we wondered what role
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    the human being played
    in this learning exercise.
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    So we ran another group of babies
    in which the kids got the same dosage,
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    the same 12 sessions,
    but over a television set.
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    And another group of babies
    who had just audio exposure
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    and looked at a teddy bear on the screen.
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    What did we do to their brains?
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    What you see here is the audio result --
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    no learning whatsoever --
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    and the video result --
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    no learning whatsoever.
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    It takes a human being
    for babies to take their statistics.
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    The social brain is controlling
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    when the babies
    are taking their statistics.
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    We want to get inside the brain
    and see this thing happening
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    as babies are in front of televisions,
    as opposed to in front of human beings.
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    Thankfully, we have a new machine,
    magnetoencephalography,
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    that allows us to do this.
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    It looks like a hair dryer from Mars.
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    But it's completely safe,
    completely noninvasive and silent.
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    And babies - we're looking at
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    millimeter accuracy
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    with regard to spatial
    and millisecond accuracy
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    using 306 SQUIDs --
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    these are superconducting
    quantum interference devices --
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    to pick up the magnetic fields
    that change as we do our thinking.
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    We're the first in the world
    to record babies in an MEG machine
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    while they are learning.
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    So this is little Emma.
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    She's a six-monther.
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    And she's listening to various languages
    in the earphones.
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    You can see, she can move around.
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    We're tracking her head
    with little pellets in a cap,
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    so she's free to move
    completely unconstrained.
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    It's a technical tour de force.
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    What are we seeing?
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    We're seeing the baby brain.
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    As the baby hears a word in her language,
    the auditory areas light up,
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    and then subsequently areas surrounding it
    that we think are related to coherence,
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    getting the brain coordinated
    with its different areas, and causality,
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    one brain area
    causing another to activate.
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    We are embarking on a grand
    and golden age.
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    We're going to be able
    to see a child's brain
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    as they experience an emotion,
    as they learn to speak and read,
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    as they solve a math problem,
    as they have an idea.
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    And we're going to be able to invent
    brain-based interventions
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    for children who have difficulty learning.
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    Just as the poets and writers described,
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    we're going to be able to see, I think,
    that wondrous openness,
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    utter and complete openness,
    of the mind of a child.
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    In investigating the child's brain,
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    we're going to uncover deep truths
    about what it means to be human,
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    and in the process,
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    we may be able to help keep
    our own minds open to learning
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    for our entire lives.
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    Thank you.
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    (Applause)
Title:
The linguistic genius of babies | Patricia Kuhl | TEDxRainier
Description:

Patricia Kuhl shares astonishing findings about how babies learn one language over another -- by listening to the humans around them and "taking statistics" on the sounds they need to know. Clever lab experiments (and brain scans) show how 6-month-old babies use sophisticated reasoning to understand their world.

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Video Language:
English
Team:
TED
Project:
TEDxTalks
Duration:
10:14
TED Translators admin edited English subtitles for TEDxRainier - Dr. Patricia Kuhl
TED Translators admin edited English subtitles for TEDxRainier - Dr. Patricia Kuhl

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