Name: 【TED】南希‧坎維西爾: 人類心智的神經圖像：瑞士刀 (Nancy Kanwisher: A neural portrait of the human mind)
Uploaded: 2014-10-24T16:54:00.000Z
Duration: 17 min 45 s

Today I want to tell you about a project being carried out by scientists all over the world

今天 我要分享一個 全科學家都在努力進行的研究:

to paint a neural portrait of the human mind.

is that the human mind and brain is not a single, general-purpose processor,

人類的思想與大腦 並非只是個通用型處理器

but a collection of highly specialized components,

而是高度專業化組件所形成的集合體

each solving a different specific problem,

每個組件都能用來解決特定問題

and yet collectively making up who we are as human beings and thinkers.

人類的思想便是由這些組件共同集合而成

To give you a feel for this idea, imagined the following scenario:

為了讓你們理解這個概念 來想像一下這個場景

You walk into your child's daycare center.

As usual, there's a dozen kids there, waiting to get picked up.

像平常一樣 有十幾個小孩待在一起 等人來接

But this time, the children's faces look weirdly similar,

但這次 孩子們的臉看起來異常相似

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

You run through a quick mental checklist.

And everything looks normal, except the children's faces.

一切看起來都很正常 除了孩子的臉

You can see the faces, but they don't look distinctive,

你看著這些小臉 每張臉都很普通

and it's only by spotting an orange hair ribbon that you find your daughter.

最後 你靠著頭上的橘色蝴蝶結 認出自己的女兒

This sudden lost of the ability to recognize faces actually happens to people.

這種突發性的臉部辨識障礙 是真實病例

and it results from damage to a particular part of the brain.

The striking thing about it is that only face recognition is impaired,

臉盲症最特別的是 除了無法辨識人臉以外

So prosopagnosia is one of many surprisingly specific mental deficits that can happen after brain damage.

腦部受損後 可能會有各種奇特症狀 臉盲症只是其中之一

These syndromes collectively have suggested for a long time

長期以來 這種種症狀 都暗示著

that the mind is divvied up into distinct components,

大腦可分為數個不同的認知區域

but the effort to discover those components has jumped to warp speed

這些認知區域的研究 近來急速發展

with the invention of brain imaging technology,

這得歸功於大腦影像技術的發明

So MRI enables you to see internal anatomy at high resolution.

核磁共振能使人清晰看見人體內部結構

a set of MRI cross-sectional images through a familiar object,

and we're going to fly through them and you're going to try to figure out what the object is. Here we go.

我們會快速展示圖像 讓各位來猜猜這些是甚麼 開始

starting from the bottom and going through the top.

Broccoli! It's a head of broccoli. It's it beautiful? I love that.

花椰菜! 這是顆花椰菜 美吧? 我好愛這個

It's a brain, of course. In fact, it's my brain.

很明顯 這是腦部 其實這是我的腦

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

That's my nose over on the right, and now we're going over here. Right there.

右邊是我的鼻子 現在正通過這裡 就是這

The really cool advance with functional imaging happened when scientists figured out

最酷的影像技術進展是 科學家研究出

how to make pictures that show not just anatomy but activity,

如何讓影像不再只顯現解剖構造 而是生物活動

Brains are like muscles. When they get active,

they need increased blood flow to supply that activity,

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

幸運的是 大腦自身能控制血液流量

So if a bunch of neurons, say, right there get active and start firing,

解設這裡有叢神經元開始運作 活躍起來

then blood flow increases just right there.

So functional MRI picks up on that blood flow increase,

功能性的核磁共振偵測到血流增加

producing a higher MRI response where neural activity goes up.

So to give you a concrete feel for how a functional MRI experiment goes

為了讓各位能具體理解功能性核磁共振實驗的進行

and what you can learn from it and what you can't,

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

我來描述一個以前我進行過的研究

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

當時我們想知道 某個大腦部位是不是專門用來辨識人臉

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

已經有足夠理由顯示 這可能是真的

based on this phenomenon of prosopagnosia that I described a moment ago.

也就是 基於我剛剛說到的臉盲症現象

But nobody had ever seen that part of the brain in a normal person,

但沒人在普通人的腦部看過這個部位

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

I held my head as still as I could while staring at pictures of faces

頭像這樣保持不動 盯著一張張臉部照片

看臉部…再看物品…看了好幾個小時

So as somebody who has pretty close to the world record of total number of hours spent inside a MRI scanner,

我在核磁共振裡的時間 久到快破世界紀錄

I can tell you that one of the skills that's really important for MRI research

所以我敢告訴你 從事核磁共振研究的必備技能之一是

When I got out of the scanner, I did a quick analysis of the data,

我踏出掃描儀後 將資料快速進行分析

looking for any parts of my brain that produced a higher response when I was looking at faces than when I was looking at objects,

尋找看著臉部時 大腦反應較強的部位

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

以今日的科技水準來看 這圖很糟

but at the time I thought it was beautiful.

What it shows is that region right there, that little blob,

and it's on the bottom surface of my brain about an inch straight in from right there.

在腦部表面下緣 離這邊只有一英吋

And what that part of my brain is doing is producing a higher MRI response,

核磁共振顯示我大腦的這個部位反應較大

that is, higher neural activity, when I was looking at faces

也就是 我看著臉部時 這裡有較強烈的神經活動

Well, the easiest way is to just do the experiment again.

最簡單的方法就是 再做一次實驗

So I got back in the scanner, I looked at more faces and I looked at more objects

所以我回到掃描儀中 看更多的臉部和物品

and around about then I decided to believe it was for real.

But still, maybe this is something weird about my brain

但這還是有可能是我大腦的特殊反應

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

So to find out, we scanned a bunch of other people and found that

所以我們找了其他受試者做實驗

pretty much everyone has that little face-processing region

發現 幾乎每個人腦都有著這個臉部辨識的小區域

So the next question was, what does this thing really do?

下個問題是 這個區域實際的工作究竟是什麼