ABOUT THE SPEAKER

Nancy Kanwisher - Brain researcher
Using fMRI imaging to watch the human brain at work, Nancy Kanwisher’s team has discovered cortical regions responsible for some surprisingly specific elements of cognition.

Why you should listen

Does the brain use specialized processors to solve complex problems, or does it rely instead on more general-purpose systems?

This question has been at the crux of brain research for centuries. MIT researcher Nancy Kanwisher seeks to answer this question by discovering a “parts list” for the human mind and brain. "Understanding the nature of the human mind," she says, "is arguably the greatest intellectual quest of all time."

Kanwisher and her colleagues have used fMRI to identify distinct sites in the brain for face recognition, knowing where you are, and thinking about other people’s thoughts. Yet these discoveries are a prelude to bigger questions: How do these brain regions develop and function? What are the actual computations that go on in each region, and how are these computations implemented in circuits of neurons? And how do these work together to produce human intelligence?

To learn more, see Kanwisher's collection of short talks on how scientists actually study the human mind and brain and what they have learned so far.

More profile about the speaker
Nancy Kanwisher | Speaker | TED.com

TED2014

Nancy Kanwisher: A neural portrait of the human mind

Nancy Kanwisher: Un retrato neural da mente humana

Filmed: 2014-03-14

Readability: 4.2

1,226,930 views

A pioneira da tecnoloxía de imaxe do cerebro Nancy Kanwisher, que usa a imaxe por resonancia magnética funcional para ver a actividade das rexións cerebrais (frecuentemente as propias), comparte o que ela e mais os seus colegas aprenderon: O cerebro está constituído por compoñentes moi especializados e tamén por "maquinaria" polivalente. Outra sorpresa: que aínda nos falta moito por aprender.

Nancy Kanwisher - Brain researcher
Using fMRI imaging to watch the human brain at work, Nancy Kanwisher’s team has discovered cortical regions responsible for some surprisingly specific elements of cognition. Full bio

Double-click the English transcript below to play the video.

00:12

Today I want to tell you

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Hoxe quérovos falar

00:13

about a project being carried out

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dun proxecto que están a levar a cabo

00:15

by scientists all over the world

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científicos de todo o mundo

00:18

to paint a neural portrait of the human mind.

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para esbozar un retrato neuronal
da mente humana.

00:21

And the central idea of this work

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A idea central deste traballo

00:23

is that the human mind and brain

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é que a mente e mais o cerebro humanos

00:25

is not a single, general-purpose processor,

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non son un só procesador
cunha única finalidade xeral,

00:28

but a collection of highly specialized components,

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senón unha agrupación de compońentes
altamente especializados,

00:31

each solving a different specific problem,

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que resolven cadanseu problema específico,

00:34

and yet collectively making up

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e que colectivamente constitúen

00:37

who we are as human beings and thinkers.

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quen somos nós como seres humanos
e pensadores.

Para que comprendades esta idea,

00:41

To give you a feel for this idea,

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00:43

imagine the following scenario:

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imaxinade o seguinte escenario:

00:45

You walk into your child's day care center.

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Entrades na gardería da vosa filla.

00:47

As usual, there's a dozen kids there

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Coma decotío, hai unha
ducia de cativas alí

00:50

waiting to get picked up,

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agardando para seren recollidas.

00:51

but this time,

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Pero desta volta,

00:53

the children's faces look weirdly similar,

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as caras das nenas son
estrańamente semellantes,

00:56

and you can't figure out which child is yours.

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e non sodes quen de recońecer
cal das nenas é a vosa.

00:59

Do you need new glasses?

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Necesitades lentes novas?

01:00

Are you losing your mind?

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Estades perdendo a cabeza?

01:02

You run through a quick mental checklist.

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Facedes axińa un repaso mental.

Non, parece que podedes pensar
con claridade,

01:05

No, you seem to be thinking clearly,

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01:07

and your vision is perfectly sharp.

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e a vosa visión é perfectamente nítida.

01:09

And everything looks normal

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Todo semella normal

01:11

except the children's faces.

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agás as caras das nenas.

Podedes ver tódalas caras,

01:13

You can see the faces,

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pero non apreciades diferenza ningunha,

01:15

but they don't look distinctive,

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01:17

and none of them looks familiar,

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e ningunha delas vos é familiar;

01:18

and it's only by spotting an orange hair ribbon

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só cando albiscades
unha cinta do pelo laranxa

01:21

that you find your daughter.

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atopades á vosa filla.

01:23

This sudden loss of the ability to recognize faces

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Esta perda súbita da capacidade
para recońecer caras

01:26

actually happens to people.

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acontécelle realmente á xente.

01:28

It's called prosopagnosia,

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Chámase prosopagnosia,

01:30

and it results from damage

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e é consecuencia dun dano

01:31

to a particular part of the brain.

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nunha zona particular do cerebro.

01:33

The striking thing about it

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O rechamante disto

01:35

is that only face recognition is impaired;

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é que só resulta danado
o recońecemento de caras;

01:37

everything else is just fine.

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todo o demais está intacto.

01:40

Prosopagnosia is one of many surprisingly specific

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A prosopagnosia é unha das moitas
patoloxías mentais

01:44

mental deficits that can happen after brain damage.

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sorprendentemente específicas
que poden acontecer tras un dano cerebral.

Estas síndromes, en conxunto,

01:48

These syndromes collectively

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01:49

have suggested for a long time

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veńen suxerindo desde hai moito

01:52

that the mind is divvied up into distinct components,

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que a mente está dividida
en diferentes compońentes,

01:55

but the effort to discover those components

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pero o esforzo por descubrir
eses compońentes

01:58

has jumped to warp speed

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acelerouse coa invención

01:59

with the invention of brain imaging technology,

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da tecnoloxía de imaxe do cerebro,

02:02

especially MRI.

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especialmente a imaxe
por resonancia magnética.

02:05

So MRI enables you to see internal anatomy

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A resonancia magnética permítenos
ver a anatomía interna

02:08

at high resolution,

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cunha alta resolución.

02:10

so I'm going to show you in a second

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Vouvos amosar nuns intres

02:11

a set of MRI cross-sectional images

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un conxunto de imaxes transversais
de resonancia ragnética

02:15

through a familiar object,

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dun obxecto familiar.

02:16

and we're going to fly through them

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Ímolas pasar moi rápido

02:17

and you're going to try to figure out what the object is.

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e ides tentar descifrar que obxecto é.

02:20

Here we go.

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Imos aló.

Non é tan sinxelo. É unha alcachofa.

02:24

It's not that easy. It's an artichoke.

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De acordo, imos tentar outra,

02:26

Okay, let's try another one,

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02:27

starting from the bottom and going through the top.

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comezando pola base e indo cara a cúspide.

Brócoli! é unha cabeza de brócoli.

02:32

Broccoli! It's a head of broccoli.

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02:33

Isn't it beautiful? I love that.

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Non é bonita? Encántame.

02:35

Okay, here's another one. It's a brain, of course.

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Velaquí temos outra.
É un cerebro, por suposto.

De feito é o meu cerebro.

02:38

In fact, it's my brain.

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Estamos atravesando capas
da mińa cabeza así

02:39

We're going through slices through my head like that.

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02:41

That's my nose over on the right, and now

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Ese é o meu nariz arriba á dereita,

02:43

we're going over here, right there.

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e agora andamos por aquí,
exactamente aquí.

02:46

So this picture's nice, if I do say so myself,

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Esta imaxe é bonita, aínda
que estea mal que o diga eu,

pero só amosa anatomía.

02:51

but it shows only anatomy.

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O avance realmente extraordinario
coa imaxe funcional

02:53

The really cool advance with functional imaging

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aconteceu cando a comunidade científica
descubriu como facer imaxes

02:55

happened when scientists figured out how to make

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02:57

pictures that show not just anatomy but activity,

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que amosen non só anatomía,
senón tamén actividade.

03:00

that is, where neurons are firing.

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É dicir, onde están activas as neuronas.

Así é como funciona:

03:03

So here's how this works.

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os cerebros son como músculos.

03:04

Brains are like muscles.

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03:05

When they get active,

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Cando se activan,

necesitan que aumente o fluxo sanguíneo
para abastecer esa actividade,

03:07

they need increased blood flow to supply that activity,

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03:10

and lucky for us, blood flow
control to the brain is local,

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e por sorte para nós, o control
do fluxo sanguíneo ao cerebro é local.

03:14

so if a bunch of neurons, say, right there

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De xeito que se un grupo de neuronas
por aquí

03:16

get active and start firing,

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comezan a se activar,

03:17

then blood flow increases just right there.

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o fluxo sanguíneo aumenta xusto aquí.

A resonancia magnética funcional
capta ese aumento de fluxo sanguíneo

03:20

So functional MRI picks up
on that blood flow increase,

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e produce unha resposta máis alta

03:24

producing a higher MRI response

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03:26

where neural activity goes up.

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alí onde aumenta a actividade neuronal.

Para pońervos un exemplo concreto

03:29

So to give you a concrete feel

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de como funciona un experimento
con resonancia magnética funcional,

03:30

for how a functional MRI experiment goes

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03:33

and what you can learn from it

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que podemos detectar nel

03:34

and what you can't,

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e que non podemos,

vou describir un dos primeiros
estudos que fixen.

03:36

let me describe one of the first studies I ever did.

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Queríamos ver se algunha zona cerebral se
especializaba no recońecemento de caras,

03:39

We wanted to know if there was a special
part of the brain for recognizing faces,

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03:43

and there was already reason to
think there might be such a thing

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e xa había razóns para pensar
que tal zona existía,

baseadas neste fenómeno da prosopagnosia

03:46

based on this phenomenon of prosopagnosia

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03:48

that I described a moment ago,

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que describín hai un momento,

03:50

but nobody had ever seen that part of the brain

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pero ninguén a vira nunca

03:52

in a normal person,

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nunha persoa normal,

03:54

so we set out to look for it.

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así que nos dispuxemos a buscala.

03:56

So I was the first subject.

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Eu fun o primeiro suxeito.

Metinme no escáner, deiteime boca arriba,

03:58

I went into the scanner, I lay on my back,

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04:01

I held my head as still as I could

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mantiven a cabeza tan inmóbil como puiden

04:03

while staring at pictures of faces like these

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mentres miraba fixamente imaxes
de caras coma estas

e obxectos coma estes,

04:08

and objects like these

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e caras, e obxectos... durante horas.

04:10

and faces and objects for hours.

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Como alguén que se aproxima
ao récord mundial

04:15

So as somebody who has
pretty close to the world record

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04:18

of total number of hours spent inside an MRI scanner,

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de horas botadas dentro dun escáner
de resonancia magnética,

04:22

I can tell you that one of the skills

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podo dicir que unha das habilidades

04:23

that's really important for MRI research

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máis importantes na investigación
con resonancia ragnética

04:26

is bladder control.

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é o control da vexiga.

04:28

(Laughter)

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(Risas)

04:29

When I got out of the scanner,

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Cando saín do escáner

04:31

I did a quick analysis of the data,

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fixen unha rápida análise dos datos,

buscando zonas do meu cerebro

04:33

looking for any parts of my brain

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04:35

that produced a higher response
when I was looking at faces

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que amosasen unha reacción máis forte
cando miraba caras

04:38

than when I was looking at objects,

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ca cando miraba obxectos.

04:39

and here's what I saw.

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E isto foi o que atopei:

Esta imaxe parece horríbel
segundo os patróns de hoxe en día,

04:42

Now this image looks just awful by today's standards,

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04:45

but at the time I thought it was beautiful.

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pero naquel momento eu atopeina fermosa.

04:48

What it shows is that region right there,

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O que amosa é esa rexión de aí,

04:50

that little blob,

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esa manchiña,

do tamańo dunha oliva

04:51

it's about the size of an olive

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04:53

and it's on the bottom surface of my brain

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que está na base do meu cerebro

04:55

about an inch straight in from right there.

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a unha polgada de profundidade dende aquí.

04:58

And what that part of my brain is doing

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E o que fai esa parte do meu cerebro

é xerar unha resposta máis alta
na resonancia magnética,

05:01

is producing a higher MRI response,

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é dicir, unha actividade neuronal
máis intensa,

05:04

that is, higher neural activity,

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05:06

when I was looking at faces

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cando eu miraba caras

05:07

than when I was looking at objects.

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ca cando miraba obxectos.

05:10

So that's pretty cool,

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Isto está moi ben,

05:11

but how do we know this isn't a fluke?

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pero como sabemos que non é casualidade?

05:13

Well, the easiest way

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Pois a maneira máis sinxela

05:15

is to just do the experiment again.

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é facer de novo o experimento.

05:17

So I got back in the scanner,

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Así que volvín ao escáner,

05:18

I looked at more faces and I looked at more objects

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mirei máis caras e máis obxectos

05:21

and I got a similar blob,

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e obtiven unha mancha semellante,

05:23

and then I did it again

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e despois fíxeno outra vez,

05:25

and I did it again

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e outra vez,

05:27

and again and again,

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e outra, e outra,

05:30

and around about then

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e foi nese momento

05:31

I decided to believe it was for real.

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cando decidín crer que era real.

05:34

But still, maybe this is
something weird about my brain

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Pero aínda así, podía tratarse de algo
estrańo no meu cerebro

e que ninguén máis tivese aí esa mancha,

05:38

and no one else has one of these things in there,

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así que para descubrilo,
escaneamos un grupo de persoas

05:40

so to find out, we scanned a bunch of other people

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05:43

and found that pretty much everyone

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e atopamos que case todas

tińan esa pequena rexión
para o procesamento de caras

05:45

has that little face-processing region

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05:47

in a similar neighborhood of the brain.

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nunha zona similar do cerebro.

Así que a seguinte cuestión era:

05:50

So the next question was,

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que raio fai esa cousa realmente?

05:52

what does this thing really do?

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05:53

Is it really specialized just for face recognition?

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Está especializada soamente
no recońecemento de caras?

Se cadra non, verdade?

05:57

Well, maybe not, right?

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05:58

Maybe it responds not only to faces

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Se cadra non só reacciona con caras

06:00

but to any body part.

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senón con calquera parte do corpo.

Podería reaccionar
con calquera cousa humana,

06:02

Maybe it responds to anything human

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ou algo vivo,

06:05

or anything alive

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ou algo redondo.

06:07

or anything round.

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O único xeito de estar realmente seguros
de que esa rexión

06:08

The only way to be really sure that that region

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06:10

is specialized for face recognition

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está especializada
no recońecemento de caras

06:13

is to rule out all of those hypotheses.

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é descartar todas esas hipóteses.

Así que botamos boa parte
dos seguintes dous anos

06:15

So we spent much of the next couple of years

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escaneando suxeitos

06:18

scanning subjects while they looked at lots

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mentres ollaban moreas de imaxes
de diferentes tipos,

06:20

of different kinds of images,

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06:21

and we showed that that part of the brain

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e observamos que esa parte do cerebro

reacciona fortemente cando miramos

06:23

responds strongly when you look at

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imaxes de caras de calquera tipo,

06:25

any images that are faces of any kind,

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e reacciona moito menos

06:29

and it responds much less strongly

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con calquera imaxe que non sexa unha cara,

06:31

to any image you show that isn't a face,

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como algunhas destas.

06:34

like some of these.

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06:35

So have we finally nailed the case

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Podemos entón concluír definitivamente

que esta rexión é necesaria para
o recońecemento de caras?

06:37

that this region is necessary for face recognition?

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Non.

06:41

No, we haven't.

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A tecnoloxía de imaxe do cerebro
non pode revelar nunca

06:42

Brain imaging can never tell you

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06:44

if a region is necessary for anything.

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se unha rexión é necesaria para algo.

06:46

All you can do with brain imaging

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Todo o que se pode facer con ela

06:48

is watch regions turn on and off

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é ver rexións acenderse e apagarse

06:50

as people think different thoughts.

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mentres a persoa
pensa en diferentes cousas.

06:52

To tell if a part of the brain is
necessary for a mental function,

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Para saber se unha parte do cerebro
é necesaria para unha función mental

06:55

you need to mess with it and see what happens,

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fai falla enredar con ela
e ver que é o que pasa,

06:58

and normally we don't get to do that.

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e normalmente non chegamos a facer iso.

07:00

But an amazing opportunity came about

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Pero tivemos unha oportunidade magnífica

cando moi recentemente
un par de colegas meus

07:03

very recently when a couple of colleagues of mine

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fixeron probas con este home,
que sofre epilepsia

07:05

tested this man who has epilepsy

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07:08

and who is shown here in his hospital bed

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e que podemos ver aquí
na súa cama do hospital.

Ten postos eléctrodos

07:11

where he's just had electrodes placed

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07:12

on the surface of his brain

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na superficie do cerebro

para identificar a orixe dos seus ataques.

07:14

to identify the source of his seizures.

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07:17

So it turned out by total chance

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Así que, de pura casualidade

07:20

that two of the electrodes

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resultou que dous dos eléctrodos

07:22

happened to be right on top of his face area.

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estaban xusto enriba da área das caras.

07:25

So with the patient's consent,

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Así que co consentimento do paciente,

07:27

the doctors asked him what happened

186

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2587

os doutores preguntáronlle que acontecía

07:30

when they electrically stimulated
that part of his brain.

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cando estimulaban electricamente
esa parte do cerebro.

O paciente non sabía

07:34

Now, the patient doesn't know

188

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1654

onde estaban eses eléctrodos,

07:35

where those electrodes are,

189

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1384

e nunca escoitara falar
da rexión cerebral das caras.

07:37

and he's never heard of the face area.

190

445362

2212

07:39

So let's watch what happens.

191

447574

1991

Vexamos que acontece.

Comeza cunha condición control:

07:41

It's going to start with a control condition

192

449565

1969

07:43

that will say "Sham" nearly invisibly

193

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2407

aparece "Sham" [falso]
case de xeito invisible

07:45

in red in the lower left,

194

453941

1710

en vermello na parte inferior esquerda

07:47

when no current is delivered,

195

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2282

cando non se lle aplica corrente.

07:49

and you'll hear the neurologist speaking
to the patient first. So let's watch.

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Primeiro ouviredes ao neurólogo
falando co paciente. Vexamos.

07:53

(Video) Neurologist: Okay, just look at my face

197

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2081

Neurólogo: Mira a mińa cara

e dime qué pasa cando fago isto.

07:55

and tell me what happens when I do this.

198

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3285

De acordo?

07:59

All right?

199

467114

934

Paciente: Vale.

08:00

Patient: Okay.

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2823

Neurólogo: Un, dous, tres.

08:02

Neurologist: One, two, three.

201

470871

4320

[Paciente: Nada]

08:07

Patient: Nothing.
Neurologist: Nothing? Okay.

202

475191

3015

Neurólogo: Nada? Vale.
Vouno facer unha vez máis.

08:10

I'm going to do it one more time.

203

478206

2407

08:12

Look at my face.

204

480613

3194

Mira a mińa cara.

Un, dous, tres.

08:15

One, two, three.

205

483807

4500

[Paciente: Acabas de transformarte
noutra persoa.]

08:20

Patient: You just turned into somebody else.

206

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2824

[A túa cara sufriu unha metamorfose.]

08:23

Your face metamorphosed.

207

491131

2137

[O teu nariz volveuse fláccido,
caeu cara á esquerda.]

08:25

Your nose got saggy, it went to the left.

208

493268

3011

08:28

You almost looked like somebody I'd seen before,

209

496279

3536

[Asemellábaste a alguén que xa vira antes]

08:31

but somebody different.

210

499815

2634

[pero non eras ti]

[Foi unha alucinación]

08:34

That was a trip.

211

502449

2072

(Gargallada)

08:36

(Laughter)

212

504521

3132

08:39

Nancy Kanwisher: So this experiment —

213

507653

1615

Este experimento

(Aplauso)

08:41

(Applause) —

214

509268

4223

...este experimento esclarece finalmente
a cuestión

08:45

this experiment finally nails the case

215

513491

2682

de que esta rexión do cerebro

08:48

that this region of the brain is not only

216

516173

1825

non soamente reacciona
selectivamente ás caras

08:49

selectively responsive to faces

217

517998

2137

senón que está causalmente relacionada
coa percepción de caras.

08:52

but causally involved in face perception.

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520135

3045

Repasei todos estes detalles sobre
a rexión das caras

08:55

So I went through all of these details

219

523180

2130

08:57

about the face region to show you what it takes

220

525310

2464

para amosarvos que é o que fai falla

08:59

to really establish that a part of the brain

221

527774

2339

para confirmar que unha parte do cerebro

09:02

is selectively involved in a specific mental process.

222

530113

3128

está relacionada
cun proceso mental específico.

09:05

Next, I'll go through much more quickly

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2159

De seguido vou amosar moito máis á présa

09:07

some of the other specialized regions of the brain

224

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2660

algunhas outras rexións do cerebro
especializadas

09:10

that we and others have found.

225

538060

2100

que nós e mais outros grupos atopamos.

09:12

So to do this, I've spent a lot of time

226

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2114

Botei moito tempo no escáner

o último mes

09:14

in the scanner over the last month

227

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1867

para poder amosárvolas no meu cerebro.
Así que, imos aló!

09:16

so I can show you these things in my brain.

228

544141

2261

09:18

So let's get started. Here's my right hemisphere.

229

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3233

Aquí está o meu hemisferio dereito.

Estades vendo a mińa cabeza dende aquí.

09:21

So we're oriented like that.
You're looking at my head this way.

230

549635

2662

Imaxinade que quitamos o cranio

09:24

Imagine taking the skull off

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1093

e vemos a superficie do cerebro así.

09:25

and looking at the surface of the brain like that.

232

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2268

Como podedes ver

09:27

Okay, now as you can see,

233

555658

1758

a superficie do cerebro está
completamente pregada.

09:29

the surface of the brain is all folded up.

234

557416

1503

Iso non é bo, podería haber
cousas agochadas aí dentro.

09:30

So that's not good. Stuff could be hidden in there.

235

558919

1721

09:32

We want to see the whole thing,

236

560640

1434

Querémolo ver enteiro,

09:34

so let's inflate it so we can see the whole thing.

237

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3312

así que o imos inchar
para podelo ver completo.

09:37

Next, let's find that face area I've been talking about

238

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2829

Agora busquemos esa área das caras
da que estiven falando,

09:40

that responds to images like these.

239

568215

2227

que reacciona ante imaxes coma estas.

Para vela, viremos o cerebro

09:42

To see that, let's turn the brain around

240

570442

1519

e observemos a superficie interna
da parte inferior.

09:43

and look on the inside surface on the bottom,

241

571961

2019

09:45

and there it is, that's my face area.

242

573980

2305

E velaquí a temos,
esa é a mińa área das caras.

09:48

Just to the right of that is another region

243

576285

2707

Xusto á dereita desa hai outra rexión,

09:50

that is shown in purple

244

578992

1638

sinalada en cor morada,

09:52

that responds when you process color information,

245

580630

3072

que reacciona cando procesamos
información sobre cores;

09:55

and near those regions are other regions

246

583702

2691

e preto desas rexións hai outras

09:58

that are involved in perceiving places,

247

586393

2363

implicadas na percepción de lugares.

Agora mesmo estou vendo a disposición
do espazo ao meu redor

10:00

like right now, I'm seeing
this layout of space around me

248

588756

2838

10:03

and these regions in green right there

249

591594

1752

e esas rexións verdes de aí

10:05

are really active.

250

593346

1274

están moi activas.

10:06

There's another one out on the outside surface again

251

594620

2370

Hai outra na superficie exterior,

onde atopamos tamén
outro par de rexións das caras.

10:08

where there's a couple more face regions as well.

252

596990

2805

10:11

Also in this vicinity

253

599795

2345

Moi preto destas

hai unha rexión específica

10:14

is a region that's selectively involved

254

602140

1645

para o procesamento do movemento
que percibimos visualmente

10:15

in processing visual motion,

255

603785

1936

10:17

like these moving dots here,

256

605721

1504

coma eses puntos móbiles de aí;

10:19

and that's in yellow at the bottom of the brain,

257

607225

2689

é esa marela da parte inferior.

10:21

and near that is a region that responds

258

609914

3168

Preto de aí hai unha rexión que reacciona

cando miramos imaxes de corpos
e partes do corpo

10:25

when you look at images of bodies and body parts

259

613082

2897

10:27

like these, and that region is shown in lime green

260

615979

2745

coma estas; a rexión amósase en verde lima

10:30

at the bottom of the brain.

261

618724

2003

na parte inferior do cerebro.

10:32

Now all these regions I've shown you so far

262

620727

2632

Todas esas rexións que amosei
ata o de agora

10:35

are involved in specific aspects of visual perception.

263

623359

4432

están involucradas en aspectos específicos
da percepción visual.

E temos tamén rexións do cerebro
especializadas

10:39

Do we also have specialized brain regions

264

627791

2148

10:41

for other senses, like hearing?

265

629939

2813

noutros sentidos, coma a audición?

10:44

Yes, we do. So if we turn the brain around a little bit,

266

632752

3037

Si! Se viramos un chisco o cerebro,

10:47

here's a region in dark blue

267

635789

2401

aquí hai unha rexión en azul escuro

10:50

that we reported just a couple of months ago,

268

638190

2346

da que demos conta hai un par de meses,

10:52

and this region responds strongly

269

640536

1634

e esta rexión reacciona fortemente

10:54

when you hear sounds with pitch, like these.

270

642170

3429

cando oímos sons cun ton definido,
coma estes:

10:57

(Sirens)

271

645599

2143

(Sirenas)

(Música de violonchelo)

10:59

(Cello music)

272

647742

2081

11:01

(Doorbell)

273

649823

1917

(Timbre)

11:03

In contrast, that same region
does not respond strongly

274

651740

3608

En contraste, esa mesma rexión
non reacciona así

cando oímos sons que nos son familiares

11:07

when you hear perfectly familiar sounds

275

655348

1562

11:08

that don't have a clear pitch, like these.

276

656910

2362

que non teńen un ton claro, coma estes:

11:11

(Chomping)

277

659272

2469

(Dentadas)

(Redobre de tambores)

11:13

(Drum roll)

278

661741

2200

(Cisterna)

11:15

(Toilet flushing)

279

663941

2767

11:18

Okay. Next to the pitch region

280

666708

2498

Ao lado da rexión do ton

hai outro conxunto de rexións que
reaccionan de xeito específico

11:21

is another set of regions that
are selectively responsive

281

669206

2474

11:23

when you hear the sounds of speech.

282

671680

2765

cando oímos falar a alguén.

11:26

Okay, now let's look at these same regions.

283

674445

1840

Agora vexamos estas mesmas rexións:

No hemisferio esquerdo hai
unha disposición semellante

11:28

In my left hemisphere, there's a similar arrangement —

284

676285

2468

11:30

not identical, but similar —

285

678753

1473

—non idéntica, pero semellante—

11:32

and most of the same regions are in here,

286

680226

2209

e a meirande parte das rexións
están tamén aquí.

11:34

albeit sometimes different in size.

287

682435

2002

Porén, ás veces teńen diferente tamańo.

11:36

Now, everything I've shown you so far

288

684437

2014

Todo o que vos amosei ata o de agora

11:38

are regions that are involved in
different aspects of perception,

289

686451

3026

son rexións involucradas en
diferentes aspectos da percepción:

11:41

vision and hearing.

290

689477

1833

visión e mais audición.

Contamos con rexións do cerebro
especializadas nos procesos mentais

11:43

Do we also have specialized brain regions

291

691310

1660

11:44

for really fancy, complicated mental processes?

292

692970

3435

realmente sofisticados e complicados?

11:48

Yes, we do.

293

696405

1429

Si que as temos!

11:49

So here in pink are my language regions.

294

697834

3389

Aquí en rosa
están as mińas rexións da linguaxe.

11:53

So it's been known for a very long time

295

701223

1428

É ben sabido desde hai moito

11:54

that that general vicinity of the brain

296

702651

2035

que esa zona do cerebro

11:56

is involved in processing language,

297

704686

2193

está involucrada no procesamento
da linguaxe,

11:58

but we showed very recently

298

706879

1732

pero moi recentemente demostramos

12:00

that these pink regions

299

708611

1710

que esas rexións rosas

12:02

respond extremely selectively.

300

710321

2205

reaccionan de xeito moi selectivo.

12:04

They respond when you understand
the meaning of a sentence,

301

712526

2812

Reaccionan cando entendemos
o significado dunha frase,

12:07

but not when you do other complex mental things,

302

715338

2838

pero non cando realizamos
outros procesos mentais complexos

12:10

like mental arithmetic

303

718176

2179

coma o cálculo mental

12:12

or holding information in memory

304

720355

2396

ou cando memorizamos información

12:14

or appreciating the complex structure

305

722751

2655

ou apreciamos a complexa estrutura

12:17

in a piece of music.

306

725406

2284

dunha peza musical.

A rexión máis asombrosa
que se atopou ata agora

12:21

The most amazing region that's been found yet

307

729664

2889

12:24

is this one right here in turquoise.

308

732553

3307

é esta turquesa de aquí.

12:27

This region responds

309

735860

2190

Esta rexión reacciona

12:30

when you think about what another person is thinking.

310

738050

4268

cando pensamos sobre
o que outra persoa está pensando.

12:34

So that may seem crazy,

311

742318

1644

Iso pode soar a tolemia,

12:35

but actually, we humans do this all the time.

312

743962

3868

pero realmente, os seres humanos
facémolo todo o tempo.

12:39

You're doing this when you realize

313

747830

2193

Estades facendo isto cando vos decatades

de que a vosa parella se vai inquietar

12:42

that your partner is going to be worried

314

750023

1631

12:43

if you don't call home to say you're running late.

315

751654

2507

se non chamades para avisar
de que ides chegar tarde.

12:46

I'm doing this with that region of my brain right now

316

754161

3469

Eu estou facendo isto con esa rexión
agora mesmo

12:49

when I realize that you guys

317

757630

2281

cando me decato de que probablemente vós

12:51

are probably now wondering about

318

759911

1598

estaredes preguntándovos

sobre todo ese territorio gris
inexplorado do cerebro.

12:53

all that gray, uncharted territory in the brain,

319

761509

2547

12:56

and what's up with that?

320

764056

1964

"Que demo pasa con iso?"

12:58

Well, I'm wondering about that too,

321

766020

1685

Ben, eu estoumo preguntando tamén!

12:59

and we're running a bunch of
experiments in my lab right now

322

767705

2395

E actualmente estamos
realizando experimentos

13:02

to try to find a number of other

323

770100

2013

para tratar de atopar

outras especializacións do cerebro

13:04

possible specializations in the brain

324

772113

2032

para outras funcións mentais
que sexan moi específicas.

13:06

for other very specific mental functions.

325

774145

3368

Pero o que é máis importante,
non creo que teńamos

13:09

But importantly, I don't think we have

326

777513

2621

13:12

specializations in the brain

327

780134

1564

especializacións no cerebro

13:13

for every important mental function,

328

781698

2746

para cada función mental importante,

mesmo para funcións mentais que poden ser
críticas para a supervivencia.

13:16

even mental functions that may be critical for survival.

329

784444

3409

De feito, hai uns anos

13:19

In fact, a few years ago,

330

787853

2102

un científico do meu laboratorio

13:21

there was a scientist in my lab

331

789955

1117

13:23

who became quite convinced

332

791072

1409

chegou a crer firmemente

13:24

that he'd found a brain region

333

792481

1749

que atopara unha rexión do cerebro

13:26

for detecting food,

334

794230

1912

para percibir comida.

E o escáner rexistraba
unha resposta intensa

13:28

and it responded really strongly in the scanner

335

796142

1918

13:30

when people looked at images like this.

336

798060

2728

cando a xente miraba imaxes coma esta.

13:32

And further, he found a similar response

337

800788

2912

E ademais, atopou unha reacción similar

13:35

in more or less the same location

338

803700

1939

nunha localización semellante

13:37

in 10 out of 12 subjects.

339

805639

2001

en dez de cada doce suxeitos.

Así que estaba bastante emocionado,

13:39

So he was pretty stoked,

340

807640

2294

e ía polo laboratorio
contándolle a todo o mundo

13:41

and he was running around the lab

341

809934

1260

13:43

telling everyone that he was going to go on "Oprah"

342

811194

2002

que ía asistir

ao programa de Oprah Winfrey
co seu descubrimento.

13:45

with his big discovery.

343

813196

2018

13:47

But then he devised the critical test:

344

815214

3022

Pero despois ideou
unha proba determinante:

13:50

He showed subjects images of food like this

345

818236

3183

Amosáballes aos suxeitos imaxes de comida
coma estas,

13:53

and compared them to images with very similar

346

821419

2741

e mais imaxes con cores e formas
moi semellantes,

13:56

color and shape, but that weren't food, like these.

347

824160

3810

pero que non eran comida, coma estas.

13:59

And his region responded the same

348

827970

2131

E a súa rexión reaccionaba do mesmo xeito

14:02

to both sets of images.

349

830101

1949

a ámbolos dous grupos de imaxes.

Así que non era unha área da comida,

14:04

So it wasn't a food area,

350

832050

1327

14:05

it was just a region that liked colors and shapes.

351

833377

2771

só unha rexión á que lle prestaban
as cores e as formas.

14:08

So much for "Oprah."

352

836148

2561

Adeus, Oprah.

14:12

But then the question, of course, is,

353

840483

2225

A cuestión é, xa que logo,

como procesamos todo o demais

14:14

how do we process all this other stuff

354

842708

2126

para o que non temos
rexións especializadas do cerebro?

14:16

that we don't have specialized brain regions for?

355

844834

2970

Eu creo que a resposta é

14:19

Well, I think the answer is that in addition

356

847804

1811

que ademais deses compońentes moi
especializados que veño de describir,

14:21

to these highly specialized components
that I've been describing,

357

849615

3554

14:25

we also have a lot of very general-
purpose machinery in our heads

358

853169

3679

temos tamén unha morea de mecanismos
nas nosas cabezas, con obxectivos xerais

14:28

that enables us to tackle

359

856848

1494

que nos permiten afrontar

14:30

whatever problem comes along.

360

858342

2106

calquera problema que se presenta.

14:32

In fact, we've shown recently that

361

860448

2055

De feito, recentemente descubrimos

14:34

these regions here in white

362

862503

2068

que esas rexións brancas de aí

14:36

respond whenever you do any difficult mental task

363

864571

3411

reaccionan sempre que facemos

calquera tarefa mental difícil

14:39

at all —

364

867982

1101

—ben, das sete que probamos.

14:41

well, of the seven that we've tested.

365

869083

3571

14:44

So each of the brain regions that I've described

366

872654

2169

Así que cada rexión do cerebro

que vos describín hoxe

14:46

to you today

367

874823

1306

14:48

is present in approximately the same location

368

876129

2767

está presente máis ou menos
na mesma localización

14:50

in every normal subject.

369

878896

1742

en tódolos suxeitos normais.

Podería collervos a calquera de vós

14:52

I could take any of you,

370

880638

1623

14:54

pop you in the scanner,

371

882261

1226

metervos no escáner,

e atoparía cada unha desas rexións
no voso cerebro.

14:55

and find each of those regions in your brain,

372

883487

2285

14:57

and it would look a lot like my brain,

373

885772

1905

E asemellaríase moito ao meu cerebro,

14:59

although the regions would be slightly different

374

887677

2070

aínda que as rexións
terían lixeiras diferenzas

15:01

in their exact location and in their size.

375

889747

3564

na localización e no tamańo.

O que me parece importante deste traballo

15:05

What's important to me about this work

376

893311

2365

non son as localizacións particulares
desas rexións cerebrais,

15:07

is not the particular locations of these brain regions,

377

895676

2969

senón o simple feito de que temos
compońentes da mente e do cerebro

15:10

but the simple fact that we have

378

898645

2587

15:13

selective, specific components of mind and brain

379

901232

2568

selectivos, específicos.

15:15

in the first place.

380

903800

1648

Iso en primeiro lugar.

15:17

I mean, it could have been otherwise.

381

905448

2011

Podería ser doutro xeito!

15:19

The brain could have been a single,

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O cerebro podería ser

un único procesador
cunha finalidade xeral,

15:21

general-purpose processor,

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1495

15:23

more like a kitchen knife

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máis semellante a un coitelo

15:24

than a Swiss Army knife.

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ca a unha navalla suíza.

15:26

Instead, what brain imaging has delivered

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En lugar disto, o que as técnicas
de imaxe do cerebro amosan

15:29

is this rich and interesting picture of the human mind.

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é esta imaxe rica e interesante
da mente humana.

15:33

So we have this picture of very general-purpose

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Así que temos esta imaxe,

da maquinaria cun propósito moi xeral,

15:35

machinery in our heads

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1070

15:37

in addition to this surprising array

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ademais desta variedade sorprendente

15:39

of very specialized components.

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de compońentes tan especializados.

15:43

It's early days in this enterprise.

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Este proxecto acaba de comezar.

15:45

We've painted only the first brushstrokes

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Só demos as primeiras brochadas

15:48

in our neural portrait of the human mind.

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do noso retrato neuronal da mente humana.

As cuestións máis fundamentais
permanecen sen resolver.

15:51

The most fundamental questions remain unanswered.

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15:54

So for example, what does each
of these regions do exactly?

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Por exemplo: que fai exactamente
cada una destas rexións?

Por que necesitamos
tres áreas para caras,

15:58

Why do we need three face areas

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2142

16:00

and three place areas,

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e tres áreas para lugares?

16:02

and what's the division of labor between them?

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Como se reparten o traballo entre elas?

16:04

Second, how are all these things

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En segundo lugar: como están
todas estas cousas

16:07

connected in the brain?

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conectadas no cerebro?

16:09

With diffusion imaging,

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Con imaxe de difusión

16:10

you can trace bundles of neurons

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podemos rastrexar feixes de neuronas

16:13

that connect to different parts of the brain,

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que conectan diferentes partes do cerebro,

16:15

and with this method shown here,

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e con este método amosado aquí,

16:17

you can trace the connections of
individual neurons in the brain,

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pódemos rastrexar as conexións
de neuronas individuais no cerebro,

16:20

potentially someday giving us a wiring diagram

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o que potencialmente pode darnos algún día
un diagrama do cableado

16:23

of the entire human brain.

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do cerebro humano ao completo.

16:25

Third, how does all of this

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En terceiro lugar: como se construíu

16:27

very systematic structure get built,

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toda esta estrutura tan sistemática

16:30

both over development in childhood

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durante o desenvolvemento infantil

16:33

and over the evolution of our species?

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e mais na evolución da nosa especie?

Para abordar cuestións coma estas,

16:36

To address questions like that,

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16:38

scientists are now scanning

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a comunidade científica está escaneando

16:40

other species of animals,

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outras especies animais,

16:42

and they're also scanning human infants.

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e tamén nenas e nenos.

Moita xente xustifica o alto custo
da investigación en neurociencia

16:48

Many people justify the high
cost of neuroscience research

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3651

16:52

by pointing out that it may help us someday

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sinalando que podería axudarnos algún día

a tratar enfermidades do cerebro
coma o Alzheimer e mais o autismo.

16:55

to treat brain disorders like Alzheimer's and autism.

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3457

16:58

That's a hugely important goal,

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É un obxectivo moi importante,

17:00

and I'd be thrilled if any of my work contributed to it,

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e entusiasmaríame que o meu traballo
contribuíse a iso;

17:03

but fixing things that are broken in the world

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pero arranxar cousas rotas do mundo

17:06

is not the only thing that's worth doing.

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non é o único que paga a pena facer.

17:09

The effort to understand the human mind and brain

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O esforzo para entender a mente
e o cerebro do ser humano

17:12

is worthwhile even if it never led to the treatment

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paga a pena mesmo se non chegase
nunca a conducir

17:15

of a single disease.

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ao tratamento dunha soa enfermidade.

17:17

What could be more thrilling

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Que podería ser máis emocionante

17:19

than to understand the fundamental mechanisms

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ca comprender os mecanismos fundamentais

17:22

that underlie human experience,

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que subxacen á experiencia humana,

17:24

to understand, in essence, who we are?

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ca comprender, en esencia, quen somos?

17:27

This is, I think, the greatest scientific quest

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Isto é, creo, a maior misión científica

17:31

of all time.

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de tódolos tempos.

17:34

(Applause)

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(Aplauso)

Translated by L.Carmela Darriba
Reviewed by Servizo de Normalización Lingüística

ABOUT THE SPEAKER

Nancy Kanwisher - Brain researcher
Using fMRI imaging to watch the human brain at work, Nancy Kanwisher’s team has discovered cortical regions responsible for some surprisingly specific elements of cognition.

Why you should listen

Does the brain use specialized processors to solve complex problems, or does it rely instead on more general-purpose systems?

This question has been at the crux of brain research for centuries. MIT researcher Nancy Kanwisher seeks to answer this question by discovering a “parts list” for the human mind and brain. "Understanding the nature of the human mind," she says, "is arguably the greatest intellectual quest of all time."

Kanwisher and her colleagues have used fMRI to identify distinct sites in the brain for face recognition, knowing where you are, and thinking about other people’s thoughts. Yet these discoveries are a prelude to bigger questions: How do these brain regions develop and function? What are the actual computations that go on in each region, and how are these computations implemented in circuits of neurons? And how do these work together to produce human intelligence?

To learn more, see Kanwisher's collection of short talks on how scientists actually study the human mind and brain and what they have learned so far.

More profile about the speaker
Nancy Kanwisher | Speaker | TED.com

THE ORIGINAL VIDEO ON TED.COM

Nancy Kanwisher: Un retrato neural da mente humana | TED Talk | TED.com