Nancy Kanwisher: A neural portrait of the human mind

Translator: Joseph Geni Reviewer: Madeleine Aronson

翻译人员: Steven Dang 校对人员: Qiwen Lu

Today I want to tell you

今天我想告诉大家一个

about a project being carried out

由全世界各地科学家一起完成的项目。

by scientists all over the world

这个项目希望用神经系统图景

to paint a neural portrait of the human mind.

来描绘人类思想。

And the central idea of this work

这一项目的中心论点，

is that the human mind and brain

就是人类的思想和大脑

is not a single, general-purpose processor,

不是一个独立、普通的处理器，

but a collection of highly specialized components,

而是一个许多高度专业化的组分的集合。

each solving a different specific problem,

其中的每一个组分都专门处理不同的问题，

and yet collectively making up

最终这些组分合在一起，

who we are as human beings and thinkers.

成就了我们人类，思考者们。

To give you a feel for this idea,

为了让你们更好地感受这一理论，

imagine the following scenario:

请想象一下接下来的场景：

You walk into your child's day care center.

你走进了你孩子的托管中心。

As usual, there's a dozen kids there

像往常一样，那里有许多的孩子

waiting to get picked up,

等待着被家长接走。

but this time,

但是在这时，

the children's faces look weirdly similar,

这些孩子们的脸庞看起来奇怪地相似，

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

你无法分辨出哪一个才是你的孩子。

Do you need new glasses?

你是需要一副新眼镜吗？

Are you losing your mind?

你是精神错乱了吗？

You run through a quick mental checklist.

你的脑海中快速地过了一遍自己的精神状况清单

No, you seem to be thinking clearly,

不，你看起来脑子很清楚，

and your vision is perfectly sharp.

你的视力也十分锐利。

And everything looks normal

所有事都看起来非常正常，

except the children's faces.

除了那些孩子们的脸。

You can see the faces,

你看着这些脸庞，

but they don't look distinctive,

可它们竟没什么差别，

and none of them looks familiar,

而且没有一张看起来熟悉。

and it's only by spotting an orange hair ribbon

你只是因为发现了一只橘色发带，

that you find your daughter.

才得以找到你的女儿。

This sudden loss of the ability to recognize faces

这种对于认脸能力的突然缺失，

actually happens to people.

经常在人们身上发生。

It's called prosopagnosia,

这种现象叫做面容失认症，

and it results from damage

它是由脑部一个特定部分损伤

to a particular part of the brain.

而引起的。

The striking thing about it

这种现象最显著的特征就是，

is that only face recognition is impaired;

只有认脸的能力被损害了，

everything else is just fine.

其他的一切都看起来很正常。

Prosopagnosia is one of many surprisingly specific

面容失认证是许多很特别的

mental deficits that can happen after brain damage.

脑部损伤产生的精神缺陷的其中一种。

These syndromes collectively

这些症状一起

have suggested for a long time

在很早之前就显示出

that the mind is divvied up into distinct components,

人的头脑是被均分成了不同的组分的。

but the effort to discover those components

但是研究这些组分的努力，

has jumped to warp speed

却因为大脑成像技术，

with the invention of brain imaging technology,

特别是MRI技术的发明

especially MRI.

而快速发展，进展迅猛。

So MRI enables you to see internal anatomy

所以MRI让你能够很清晰地

at high resolution,

看到内在的结构。

so I'm going to show you in a second

我接下来会给你们看看

a set of MRI cross-sectional images

一系列常见物体的

through a familiar object,

MRI跨区域影像。

and we're going to fly through them

我们将快速地翻动图片，

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

让你们试着猜猜那些是什么物体。

Here we go.

接下来开始了。

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

这个不太容易。这是一朵菊芋。

Okay, let's try another one,

试试另外一个。

starting from the bottom and going through the top.

从底部开始向顶部移动。

Broccoli! It's a head of broccoli.

花椰菜！这一一朵花椰菜的顶部。

Isn't it beautiful? I love that.

它很漂亮，不是吗？我很喜欢。

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

这里还有一个。当然，这是大脑。

In fact, it's my brain.

实际上，这是我的大脑。

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

我们在一部分一部分看透我的大脑。

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

刚才右边的是我的鼻子，

we're going over here, right there.

现在我们已经到了这里，就是这里。

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

要我说，这张照片挺好，

but it shows only anatomy.

可是它只展示了内部构造。

The really cool advance with functional imaging

功能性影像最酷的进步在于

happened when scientists figured out how to make

科学家找到制作出

pictures that show not just anatomy but activity,

不仅展示构造，更展示内部活动的图片。

that is, where neurons are firing.

也就是神经元的活动。

So here's how this works.

那么接下来是这项技术的原理。

Brains are like muscles.

大脑就像肌肉，

When they get active,

当大脑变得活跃时，

they need increased blood flow to supply that activity,

他们需要更多的血液来支撑这样的活动。

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

正好，控制大脑的血液就存在与大脑中。

so if a bunch of neurons, say, right there

所以比如说这儿的一些神经元

get active and start firing,

变得活跃，开始传输信号，

then blood flow increases just right there.

接下来这儿的血液流量就会增加。

So functional MRI picks up on that blood flow increase,

所以功能性MRI专门探测血流量的增加，

producing a higher MRI response

当神经活动增强时，

where neural activity goes up.

就产生更高的MRI回应。

So to give you a concrete feel

为了让你们更直观的感受

for how a functional MRI experiment goes

功能性MRI实验如何运作，

and what you can learn from it

还有你们能从中学到什么，学不到什么，

and what you can't,

让我给你们讲一讲我做过的第一个研究。

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

我们想要弄清楚大脑中到底有没有

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

一个特定的部分帮助人们分辨脸庞。

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

基于我先前提到的面容失认症的现象，

based on this phenomenon of prosopagnosia

我们有理由相信，

that I described a moment ago,

大脑中这样的部位确实存在。

but nobody had ever seen that part of the brain

但是没有人在常人的大脑中

in a normal person,

看见过这个部位。

so we set out to look for it.

所以我们开始寻找那个部位。

So I was the first subject.

我是第一个实验对象。

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

我走进扫描仪，平躺下。

I held my head as still as I could

我尽量让我的头保持静止

while staring at pictures of faces like these

看着像这些照片上的脸庞，

and objects like these

和像这些照片上的物体。

and faces and objects for hours.

人脸，物体，重复了几个小时。

So as somebody who has pretty close to the world record

作为一个已经接近

of total number of hours spent inside an MRI scanner,

在MRI扫描仪内待的时间的世界纪录的人

I can tell you that one of the skills

我能告诉你，MRI研究中其中一个

that's really important for MRI research

重要的技巧就是

is bladder control.

憋尿的本领。

(Laughter)

（笑声）

When I got out of the scanner,

我走出扫描仪后，

I did a quick analysis of the data,

我快速分析了那些数据，

looking for any parts of my brain

寻找有没有任何大脑的部分

that produced a higher response when I was looking at faces

在我看人脸时产生了比我看物体时

than when I was looking at objects,

更高的反应。

and here's what I saw.

这是我看到的数据。

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

这些图像以今天的标准来看很糟，

but at the time I thought it was beautiful.

但在当时我看来，它很漂亮。

What it shows is that region right there,

它展示了这里的一块区域，

that little blob,

这里的一小团。

it's about the size of an olive

大概和一颗橄榄差不多大。

and it's on the bottom surface of my brain

这部分在我大脑的底层，

about an inch straight in from right there.

大概从这里向里一英寸。

And what that part of my brain is doing

当我看到人脸的时候

is producing a higher MRI response,

我的大脑的这一部分

that is, higher neural activity,

比我看到物体的时候

when I was looking at faces

产生了更高的MRI反应，

than when I was looking at objects.

也就是更高的神经活动。

So that's pretty cool,

这个结果令人振奋，

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

但我们怎么能知道这是不是偶然呢？

Well, the easiest way

当然，最简单的方法，

is to just do the experiment again.

就是重复做这个实验。

So I got back in the scanner,

所以我回到了扫描仪里。

I looked at more faces and I looked at more objects

我盯着更多的人脸和更多的物体，

and I got a similar blob,

也得到了相似的结果。

and then I did it again

我又重复，

and I did it again

又重复

and again and again,

重复再重复。

and around about then

直到那时，

I decided to believe it was for real.

我才决定相信，实验结果是正确的。

But still, maybe this is something weird about my brain

但是，仍然有可是事我的大脑有些不同寻常。

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

有可能其他人都没有我那种问题。

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

为了证实实验结果，我们又扫描了其他很多人的大脑。

and found that pretty much everyone

最后发现几乎每个人的大脑里，

has that little face-processing region

在相似的位置上，

in a similar neighborhood of the brain.

都有那一小块识别人脸的区域。

So the next question was,

那么下一个问题来了，

what does this thing really do?

这个区域到底做些什么？

Is it really specialized just for face recognition?

它是专门只用来识别人脸吗？

Well, maybe not, right?

或许有可能不是这样的。

Maybe it responds not only to faces

也许它不仅仅对人脸有反应，

but to any body part.

也会对任何的人体部位有反应。

Maybe it responds to anything human

也许它会对任何与人类相关的

or anything alive

或者任何生物

or anything round.

或者任何圆形的东西起反应。

The only way to be really sure that that region

为了确定那块小区域

is specialized for face recognition

是专门用来识别人脸的，

is to rule out all of those hypotheses.

必须排除掉刚才提到的所有假设。

So we spent much of the next couple of years

所以我们花了接下来的好几年，

scanning subjects while they looked at lots

在实验对象看着许多不同种类图像时

of different kinds of images,

扫描他们的大脑。

and we showed that that part of the brain

我们证明了大脑的那一区域

responds strongly when you look at

在你看着任何种类的脸的任何图像时

any images that are faces of any kind,

会起强烈的反应。

and it responds much less strongly

当你看的是非脸庞的图像时，

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

那块区域的反应会弱很多

like some of these.

就像这些图像。

So have we finally nailed the case

那么我们是不是已经确定

that this region is necessary for face recognition?

脸庞识别必须依靠这一区域了呢？

No, we haven't.

不，我们没有。

Brain imaging can never tell you

大脑图像永远不能告诉你

if a region is necessary for anything.

任何东西是否依靠一块区域。

All you can do with brain imaging

大脑图像能让你做的

is watch regions turn on and off

只有看着当人们想着不同东西时，

as people think different thoughts.

他们大脑各个区域变得活跃或不活跃。

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

为了确定大脑的一部分是否对于精神功能至关重要，

you need to mess with it and see what happens,

你需要干扰那一部分的功能，看看会发生什么。

and normally we don't get to do that.

一般我们无法那样做。

But an amazing opportunity came about

但是，一个绝好的机会出现了。

very recently when a couple of colleagues of mine

最近我的一些同事

tested this man who has epilepsy

测试了这个在病床上躺着的

and who is shown here in his hospital bed

患有癫痫的男人。

where he's just had electrodes placed

在他大脑的表层

on the surface of his brain

刚刚被装上了电极，

to identify the source of his seizures.

来弄清他癫痫发作的来源。

So it turned out by total chance

结果是非常碰巧地，

that two of the electrodes

其中两个电极

happened to be right on top of his face area.

正好在他面部区域的顶端。

So with the patient's consent,

所以经过了患者的同意，

the doctors asked him what happened

医生问他，当电极刺激大脑那个区域时，

when they electrically stimulated that part of his brain.

发生了什么。

Now, the patient doesn't know

那时，患者还不知道

where those electrodes are,

那些电极在哪儿，

and he's never heard of the face area.

他也从未听说过面部区域。

So let's watch what happens.

让我们来看看发生了什么。

It's going to start with a control condition

一开始，会有一个控制条件。

that will say "Sham" nearly invisibly

当没有电流被输送时

in red in the lower left,

左下角会出现一个几乎看不见的

when no current is delivered,

红色字“假装的”。

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

你会听到神经学家对患者讲话。我们来看看吧。

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

（视频）神经学家：好的，看着我的脸。

and tell me what happens when I do this.

当我这样做的时候告诉我发生了些什么。

All right?

好吗？

Patient: Okay.

患者：好的。

Neurologist: One, two, three.

神经学家：一，二，三。

Patient: Nothing. Neurologist: Nothing? Okay.

患者：什么也没有发生

I'm going to do it one more time.

神经学家：什么也没有？好的，我会再做一次。

Look at my face.

看着我的脸。

One, two, three.

一，二，三。

Patient: You just turned into somebody else.

患者：你变成了另外一个人。

Your face metamorphosed.

你的脸变形了。

Your nose got saggy, it went to the left.

你的鼻子变得松弛，偏向了左边。

You almost looked like somebody I'd seen before,

你看起来就像一个我以前见过的人，

but somebody different.

但其实又不是。

That was a trip.

那是幻觉

(Laughter)

（笑声）

Nancy Kanwisher: So this experiment —

Nancy Kanwisher：那么这个实验—

(Applause) —

（掌声）—

this experiment finally nails the case

这个实验最终证实

that this region of the brain is not only

大脑这块区域

selectively responsive to faces

不仅仅有选择性地对脸庞起反应，

but causally involved in face perception.

还因此牵涉到脸的感知。

So I went through all of these details

我快速过了一遍有关

about the face region to show you what it takes

面部识别区域的细节来向你们展示

to really establish that a part of the brain

是什么真正证实大脑的一部分

is selectively involved in a specific mental process.

有选择地参与了特别的心理过程。

Next, I'll go through much more quickly

接下来我会讲得更快一些。

some of the other specialized regions of the brain

我会讲我们和其他人发现的

that we and others have found.

其他有专门功能的大脑区域。

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

过去的一个月里，为了做这件事

in the scanner over the last month

我已经在扫描仪里呆了很长时间，

so I can show you these things in my brain.

来给你们看看我大脑里的这些东西。

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

我们开始吧。这是我的右半脑。

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

我们的方向是这样的。你们在从这个方向看我的大脑。

Imagine taking the skull off

想象一下把头骨拿走，

and looking at the surface of the brain like that.

像那样看着大脑的皮层。

Okay, now as you can see,

那么，现在如你所见，

the surface of the brain is all folded up.

大脑的皮层都是有褶皱的。

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

这可不太好，可能有东西会藏在里面。

We want to see the whole thing,

我们想看看到完整的图像。

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

那我们就展开它来看到完整的东西吧。

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

接下来，我们来找一找一直都在说的那个

that responds to images like these.

对像这些图像有反应的区域吧。

To see that, let's turn the brain around

为了能看见它，我们把大脑转一圈，

and look on the inside surface on the bottom,

从底部看大脑的内部表层，

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

就是这了，这就是我的脸庞识别区域。

Just to the right of that is another region

在它的右边是另一个

that is shown in purple

标示成紫色的区域。

that responds when you process color information,

当你在处理颜色信息时它会有反应。

and near those regions are other regions

在这些区域的附近还有其他

that are involved in perceiving places,

参与感知地点的区域。

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

就像现在，我正在看着我周围的布局，

and these regions in green right there

在那这些绿色的区域

are really active.

非常的活跃。

There's another one out on the outside surface again

还有一个区域在外部的大脑皮层，

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

这儿也还有几个脸庞识别区域。

Also in this vicinity

在这附近

is a region that's selectively involved

有一个区域，专门参与

in processing visual motion,

处理可视的物体移动

like these moving dots here,

像这些移动的小点。

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

就是这个在大脑底部的黄色部分。

and near that is a region that responds

在那附近有一个区域，

when you look at images of bodies and body parts

它在你看着身体或身体的部分时会有反应

like these, and that region is shown in lime green

就是这些在大脑底部

at the bottom of the brain.

标注成酸橙绿色的区域。

Now all these regions I've shown you so far

目前为止我给你们展示的区域

are involved in specific aspects of visual perception.

都参与了特定视觉感知的处理。

Do we also have specialized brain regions

那么我们是否有大脑区域，

for other senses, like hearing?

专门处理其他感官，比如听感呢？

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

是的，我们有。如果我们稍微转转大脑。

here's a region in dark blue

这有一个深蓝色区域。

that we reported just a couple of months ago,

我们几个月前才报告了它的存在。

and this region responds strongly

当你听到像这样的有音高的声音时，

when you hear sounds with pitch, like these.

这个区域会强烈反应。

(Sirens)

(警报)

(Cello music)

（大提琴声）

(Doorbell)

（门铃）

In contrast, that same region does not respond strongly

相比之下，当你听到一些

when you hear perfectly familiar sounds

像这些没有音高的熟悉的声音时，

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

这个区域反应不会那么强烈。

(Chomping)

（咀嚼声）

(Drum roll)

（鼓声）

(Toilet flushing)

（马桶水声）

Okay. Next to the pitch region

好的。在这个区域旁边

is another set of regions that are selectively responsive

是另一堆专门对

when you hear the sounds of speech.

说话声起反应的区域。

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

现在我们来看一看这些一样的区域。

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

在我的左半脑，有相似的排列——

not identical, but similar —

不是完全一样，但是很相似——

and most of the same regions are in here,

大多数区域，尽管有时大小不同，

albeit sometimes different in size.

都排列在这里。

Now, everything I've shown you so far

目前为止我给你们展示的东西

are regions that are involved in different aspects of perception,

都是参与了不同感官，视觉和听觉，

vision and hearing.

处理的区域。

Do we also have specialized brain regions

那我们还有没有专门处理

for really fancy, complicated mental processes?

很复杂的心理活动的区域呢？

Yes, we do.

是的，我们有。

So here in pink are my language regions.

这个粉色区域是我的语言区。

So it's been known for a very long time

很早，人们就知道

that that general vicinity of the brain

大脑中的这一片区域

is involved in processing language,

参与了语言的处理，

but we showed very recently

但是我们最近才证实

that these pink regions

这些粉色区域

respond extremely selectively.

极有选择性地起反应。

They respond when you understand the meaning of a sentence,

它们在你理解一句话的意思时起反应，

but not when you do other complex mental things,

却不在你做其他复杂心理活动起反应，

like mental arithmetic

比如说心算，

or holding information in memory

或者试着记住一条信息，

or appreciating the complex structure

或者在欣赏一段音乐的

in a piece of music.

复杂结构。

The most amazing region that's been found yet

迄今为止发现的最神奇的区域

is this one right here in turquoise.

是这一片青绿色的部分。

This region responds

这片区域在你思考别人在思考什么的时候

when you think about what another person is thinking.

会有反应。

So that may seem crazy,

这可能看起来很疯狂，

but actually, we humans do this all the time.

但事实上，我们人类一直都在做这样的事。

You're doing this when you realize

当你意识到

that your partner is going to be worried

如果你不打电话回家

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

说你会跑步跑很晚，你的同伴会担心时

你的大脑在这样做。

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

我现在就在用这块区域这样做。

when I realize that you guys

我在想你们在座各位

are probably now wondering about

可能会琢磨

all that gray, uncharted territory in the brain,

剩下的那块灰色的没标识的区域

and what's up with that?

到底是起什么作用的？

Well, I'm wondering about that too,

我也在琢磨这个问题。

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

我们现在在实验室里做大量的实验

to try to find a number of other

来试着寻找其他

possible specializations in the brain

大脑可能存在的有特殊功能的

for other very specific mental functions.

高度专门化区域。

But importantly, I don't think we have

但是很重要的一点是，我不认为我们的大脑

specializations in the brain

对每一个重要的功能

for every important mental function,

甚至是关乎生存的功能

even mental functions that may be critical for survival.

都有专门处理的区域。

In fact, a few years ago,

事实上，几年前，

there was a scientist in my lab

有一位在我实验室的科学家，

who became quite convinced

非常确信地说

that he'd found a brain region

他发现了一块大脑区域

for detecting food,

专门用来识别食物。

and it responded really strongly in the scanner

在扫描仪里当人们看见这些图像时

when people looked at images like this.

这块区域会强烈反应。

And further, he found a similar response

此外，他还在12个对象的10个中的大脑中

in more or less the same location

几乎同样的区域

in 10 out of 12 subjects.

发现了相同的反应。

So he was pretty stoked,

他兴奋得不得了

and he was running around the lab

在实验室里跑跑跳跳

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

告诉每一个人他就要带着他的研究成果

with his big discovery.

上奥普拉的脱口秀了。

But then he devised the critical test:

但接下来他做了一个修正实验：

He showed subjects images of food like this

他给实验对象展示了像这样的食物图片，

and compared them to images with very similar

并用了一些在形状和颜色上相似

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

但不是食物的图片做对比。

And his region responded the same

结果是那片区域对于两套图片的

to both sets of images.

反应强度是一样的。

So it wasn't a food area,

那么那就不是一块识别食物的区域了

it was just a region that liked colors and shapes.

只是一块会对颜色和形状产生反应的区域。

So much for "Oprah."

不过这也够拿上奥普拉脱口秀的台面了。

But then the question, of course, is,

但接下来的问题就是

how do we process all this other stuff

我们怎样用非专门化的大脑区域

that we don't have specialized brain regions for?

来处理其他的信息呢？

Well, I think the answer is that in addition

我认为答案就是

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

在我刚才说到的那些高度专门化部分以外

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

我们大脑里还有很多非专业化的机件

that enables us to tackle

他们让我们能够处理

whatever problem comes along.

任何出现的困难。

In fact, we've shown recently that

事实上，我们最近证实了

these regions here in white

这些白色的区域

respond whenever you do any difficult mental task

会在你做任何困难的大脑工作时起反应。

at all —

在我们测试的七个中

well, of the seven that we've tested.

都是这样的结果。

So each of the brain regions that I've described

所以今天我给你们描述的

to you today

每一个大脑区域，

is present in approximately the same location

在正常的实验对象的大脑上

in every normal subject.

都在大概相同的位置。

I could take any of you,

我能挑你们其中的任意一个人，

pop you in the scanner,

把你塞进扫描仪，

and find each of those regions in your brain,

然后发现你大脑的那些区域

and it would look a lot like my brain,

和我大脑的区域非常相似。

although the regions would be slightly different

尽管可能这两者间

in their exact location and in their size.

会在准确的位置和大小上有所不同。

What's important to me about this work

对我而言这项工作最重要的

is not the particular locations of these brain regions,

不是那些大脑区域的准确位置，

but the simple fact that we have

而是我们得出的结论：

selective, specific components of mind and brain

我们的大脑和思想从一开始就由

in the first place.

选择性的和精细的各部分组成。

I mean, it could have been otherwise.

我的意思是，我们的大脑大可不必成为这样。

The brain could have been a single,

大脑可以是一个独立的，

general-purpose processor,

功能宽泛的处理器，

more like a kitchen knife

看起来更像一把菜刀

than a Swiss Army knife.

而不是瑞士军刀。

Instead, what brain imaging has delivered

但是，大脑成像呈现给我们的

is this rich and interesting picture of the human mind.

是人类思想的丰富的和有趣的图景。

So we have this picture of very general-purpose

这样这图片展示了大脑中

machinery in our heads

既有功能宽泛的机件，

in addition to this surprising array

也有令人惊讶的数量的

of very specialized components.

高度专门化的组分。

It's early days in this enterprise.

我们仍在这项研究的初期，

We've painted only the first brushstrokes

我们只在人类思想的神经学解释上

in our neural portrait of the human mind.

迈出了第一步。

The most fundamental questions remain unanswered.

最基本的问题仍然没有解答。

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

比如说，每个这些区域究竟是做什么的？

Why do we need three face areas

为什么我们需要三个脸部区域

and three place areas,

和三个地点区域？

and what's the division of labor between them?

它们之间的分工是怎么样的？

Second, how are all these things

第二，这些东西

connected in the brain?

和大脑又是怎样联系起来的？

With diffusion imaging,

you can trace bundles of neurons

借助弥散成像，

你能够追踪许多连接到

that connect to different parts of the brain,

大脑各个部分的神经元。

and with this method shown here,

通过这里展示的方法，

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

你就能找到单个神经元和大脑的联系。

potentially someday giving us a wiring diagram

这样也许有一天就能给我们

of the entire human brain.

一幅大脑的线路状图象。

Third, how does all of this

第三，这些非常系统的结构

very systematic structure get built,

是怎样在幼年的成长

both over development in childhood

和在物种的进化中

and over the evolution of our species?

被建立起来的呢？

To address questions like that,

为了解答这样的问题，

scientists are now scanning

科学家们现在在扫描

other species of animals,

其他种类的动物。

and they're also scanning human infants.

他们也在扫描人类婴孩。

Many people justify the high cost of neuroscience research

许多人为神经元科学研究的高成本辩护，

by pointing out that it may help us someday

他们指出这项研究也许某天会帮助我们

to treat brain disorders like Alzheimer's and autism.

治疗如阿兹海默症和自闭症这些神经紊乱。

That's a hugely important goal,

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

这是极其重要的目标，

如果我的工作能够给予帮助，我将非常激动。

but fixing things that are broken in the world

但是修理世上已经坏掉的东西

is not the only thing that's worth doing.

不是唯一值得去做的事。

The effort to understand the human mind and brain

为了了解人类心理和大脑而做出的努力

is worthwhile even if it never led to the treatment

即使无法用于治疗某种疾病

of a single disease.

也是有价值的。

What could be more thrilling

还有什么事

than to understand the fundamental mechanisms

能比了解人类体验的基础机制

that underlie human experience,

和本质上了解“我们是谁”

to understand, in essence, who we are?

更令人激动的呢？

This is, I think, the greatest scientific quest

我认为，这是有史以来

of all time.

最伟大的科学探寻

(Applause)

（掌声）