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00:00
Translator: Joseph Geni
Reviewer: Madeleine Aronson
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譯者: Jinyi Hu
審譯者: Yesbydefault 倪文娟
00:12
Today I want to tell you
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今天我想分享
00:13
about a project being carried out
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全球科學家正在進行的一項計畫,
00:15
by scientists all over the world
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00:18
to paint a neural portrait of the human mind.
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它的目的是要
畫出人類大腦的神經圖像。
00:21
And the central idea of this work
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這項工作的核心概念是,
00:23
is that the human mind and brain
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人類的心智和大腦,
00:25
is not a single, general-purpose processor,
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並非單一、通用的處理器,
00:28
but a collection of highly specialized components,
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而是許多高度分工單元的集合體,
00:31
each solving a different specific problem,
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各自負責不同的特定問題,
00:34
and yet collectively making up
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同時也聯合造就了
00:37
who we are as human beings and thinkers.
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我們之為人類和思考者。
00:41
To give you a feel for this idea,
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為了讓大家感受一下我的意思,
00:43
imagine the following scenario:
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請想像這個情景:
00:45
You walk into your child's day care center.
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你走進你孩子的托兒所,
00:47
As usual, there's a dozen kids there
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像往常一樣,你看到十幾個孩子
00:50
waiting to get picked up,
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正在等著家長來接。
00:51
but this time,
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但是這次,
00:53
the children's faces look weirdly similar,
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這些孩子的臉孔看起來出奇地相似,
00:56
and you can't figure out which child is yours.
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你認不出哪個是你的孩子,
00:59
Do you need new glasses?
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是你該換一副新眼鏡了嗎?
01:00
Are you losing your mind?
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還是你神經錯亂了?
01:02
You run through a quick mental checklist.
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你心裡快速自我檢查了一下,
01:05
No, you seem to be thinking clearly,
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還好啊,你思緒清晰,
01:07
and your vision is perfectly sharp.
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視力也沒問題,
01:09
And everything looks normal
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一切看起來都很正常,
01:11
except the children's faces.
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除了孩子們的臉孔。
01:13
You can see the faces,
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你可以看到他們的臉,
01:15
but they don't look distinctive,
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但是它們看起來沒有明顯的差別,
01:17
and none of them looks familiar,
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而且全都很陌生。
01:18
and it's only by spotting an orange hair ribbon
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後來是因為你看到一條橘色髮帶,
01:21
that you find your daughter.
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才找到你的女兒。
01:23
This sudden loss of the ability to recognize faces
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這種突然失去臉孔辨識能力的情況,
01:26
actually happens to people.
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真的發生在某些人身上,
01:28
It's called prosopagnosia,
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叫做「面容失憶症」,
01:30
and it results from damage
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是因為大腦特定部位損傷所致。
01:31
to a particular part of the brain.
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01:33
The striking thing about it
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神奇的是,
01:35
is that only face recognition is impaired;
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除了臉孔辨識能力受損以外,
01:37
everything else is just fine.
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其他一切正常。
01:40
Prosopagnosia is one of many surprisingly specific
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面容失憶症只是
許多奇特的精神疾病之一,
01:44
mental deficits that can happen after brain damage.
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都是大腦損傷後
可能產生的後遺症。
01:48
These syndromes collectively
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長久以來,這些病症一直都在暗示我們,
01:49
have suggested for a long time
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01:52
that the mind is divvied up into distinct components,
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大腦可以分成許多特殊的單元。
01:55
but the effort to discover those components
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我們對這些大腦單元的研究,
01:58
has jumped to warp speed
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近來進展神速,
01:59
with the invention of brain imaging technology,
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這要歸功於大腦造影技術的發明,
02:02
especially MRI.
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特別是 MRI 核磁共振造影。
02:05
So MRI enables you to see internal anatomy
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磁振造影能看到
高解析度的腦部結構,
02:08
at high resolution,
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02:10
so I'm going to show you in a second
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我馬上要給你們看
02:11
a set of MRI cross-sectional images
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某日常物品的一組 MRI 橫截面圖。
02:15
through a familiar object,
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02:16
and we're going to fly through them
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我會快速掃過一遍,
02:17
and you're going to try to figure out what the object is.
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看你們能不能認出這是什麼東西。
02:20
Here we go.
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開始:
02:24
It's not that easy. It's an artichoke.
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不容易認出來,是一朵朝鮮薊。
02:26
Okay, let's try another one,
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好,我們再試另一組,
02:27
starting from the bottom and going through the top.
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從底部掃到頂部。
觀眾:青花菜!
講者:一顆青花菜!
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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這不是很美嗎?我超愛這個。
02:35
Okay, here's another one. It's a brain, of course.
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好,再一個。
是大腦,很明顯。
02:38
In fact, it's my brain.
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事實上,這是我的大腦。
02:39
We're going through slices through my head like that.
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正在掃過我的頭,產生一連串縱剖面圖,
02:41
That's my nose over on the right, and now
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右邊是我的鼻子,
02:43
we're going over here, right there.
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現在掃到這裡。
02:46
So this picture's nice, if I do say so myself,
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這些照片很漂亮,如果容我這麼說,
02:51
but it shows only anatomy.
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但這只能看到解剖圖。
02:53
The really cool advance with functional imaging
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功能性造影 fMRI 最偉大的進步是
02:55
happened when scientists figured out how to make
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科學家不再只能看到大腦的「構造」,
02:57
pictures that show not just anatomy but activity,
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而能看到「活動」,
03:00
that is, where neurons are firing.
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也就是神經元活動的地方。
03:03
So here's how this works.
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原理是這樣:
03:04
Brains are like muscles.
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腦很像肌肉,
03:05
When they get active,
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活躍時,
03:07
they need increased blood flow to supply that activity,
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需要充血,以供活動所需。
03:10
and lucky for us, blood flow
control to the brain is local,
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幸好,大腦血流量控制是區域性的,
03:14
so if a bunch of neurons, say, right there
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所以,若這裡有一束神經元活躍起來,
03:16
get active and start firing,
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並且開始發射,
03:17
then blood flow increases just right there.
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就只有這裡的血流量會增加。
03:20
So functional MRI picks up
on that blood flow increase,
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所以功能性造影 fMRI
會測到這裡的血流量增加,
03:24
producing a higher MRI response
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在神經元活躍處,
產生較強的核磁共振反應。
03:26
where neural activity goes up.
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03:29
So to give you a concrete feel
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為了讓大家實際看一下,
03:30
for how a functional MRI experiment goes
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功能性造影實驗怎麼進行,
03:33
and what you can learn from it
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並且了解它的功用和限制,
03:34
and what you can't,
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03:36
let me describe one of the first studies I ever did.
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讓我介紹我早期的一項研究:
03:39
We wanted to know if there was a special
part of the brain for recognizing faces,
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我們想知道,
大腦中是否有辨識臉孔的專區。
03:43
and there was already reason to
think there might be such a thing
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當時已有理由支持這個假設,
03:46
based on this phenomenon of prosopagnosia
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因為有剛才講的「面容失憶症」病例。
03:48
that I described a moment ago,
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03:50
but nobody had ever seen that part of the brain
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但是從未有人在正常的大腦裡
找到過這個區域,
03:52
in a normal person,
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03:54
so we set out to look for it.
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所以我們開始尋找它。
03:56
So I was the first subject.
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我是第一個受試者。
03:58
I went into the scanner, I lay on my back,
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我進入掃描機,仰躺著,
04:01
I held my head as still as I could
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頭盡量保持不動,
04:03
while staring at pictures of faces like these
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一邊盯著像這些人臉的照片,
04:08
and objects like these
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以及像這些物品的圖片。
04:10
and faces and objects for hours.
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再看人臉,再看物品,連續好幾小時。
04:15
So as somebody who has
pretty close to the world record
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我待在核磁共振儀裡的時間,
久到快破世界紀錄,
04:18
of total number of hours spent inside an MRI scanner,
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04:22
I can tell you that one of the skills
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所以我可以告訴大家,
04:23
that's really important for MRI research
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做 MRI 研究要具備的一項重要技能,
04:26
is bladder control.
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就是憋尿。
04:28
(Laughter)
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(觀眾笑聲)
04:29
When I got out of the scanner,
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走出掃描儀以後,
04:31
I did a quick analysis of the data,
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我快速分析了一下數據,
04:33
looking for any parts of my brain
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看看我的大腦有沒有什麼區域
04:35
that produced a higher response
when I was looking at faces
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會在我看到人臉時,產生更強的反應,
04:38
than when I was looking at objects,
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強於看到普通物品時。
04:39
and here's what I saw.
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這是我所看到的:
04:42
Now this image looks just awful by today's standards,
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依今天的標準來看,這個影像粗糙不堪,
04:45
but at the time I thought it was beautiful.
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但當時我認為它很美。
04:48
What it shows is that region right there,
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它展示了那個區域,
04:50
that little blob,
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就是那一個小小的亮點,
04:51
it's about the size of an olive
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大概像一顆橄欖的大小,
04:53
and it's on the bottom surface of my brain
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位在我大腦的底部表層,
04:55
about an inch straight in from right there.
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大約在從這進去一吋深的地方。
04:58
And what that part of my brain is doing
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我大腦這部分所做的,
05:01
is producing a higher MRI response,
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就是產生較強的核磁共振反應,
05:04
that is, higher neural activity,
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也就是,較活躍的神經元活動,
05:06
when I was looking at faces
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這發生在當我看著人臉時,
05:07
than when I was looking at objects.
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而不是看著物品時。
05:10
So that's pretty cool,
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這非常有趣。
05:11
but how do we know this isn't a fluke?
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但我們怎知這不是巧合?
05:13
Well, the easiest way
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最簡單的方法,
05:15
is to just do the experiment again.
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就是再做一次實驗。
05:17
So I got back in the scanner,
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所以我又躺回掃描儀中,
05:18
I looked at more faces and I looked at more objects
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看了更多的臉孔,以及更多的物品,
05:21
and I got a similar blob,
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結果得到幾乎同一處亮點。
05:23
and then I did it again
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然後我又重複一遍這個實驗,
05:25
and I did it again
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再一遍,
05:27
and again and again,
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又一遍,
再一遍。
05:30
and around about then
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做完這一遍,
05:31
I decided to believe it was for real.
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我決定相信,實驗結果是正確的。
05:34
But still, maybe this is
something weird about my brain
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但是,這可能是因為我的大腦比較怪,
05:38
and no one else has one of these things in there,
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別人的大腦不會這樣。
05:40
so to find out, we scanned a bunch of other people
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為了找到答案,我們又掃描了一批人,
05:43
and found that pretty much everyone
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結果發現幾乎每個人
05:45
has that little face-processing region
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都有那一小塊臉孔辨識區域,
05:47
in a similar neighborhood of the brain.
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大約都在大腦中相似的地帶。
05:50
So the next question was,
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所以接下來的問題是,
05:52
what does this thing really do?
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這個區域到底是做什麼的?
05:53
Is it really specialized just for face recognition?
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它真的只專門辨識臉孔嗎?
05:57
Well, maybe not, right?
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不見得,對吧?
05:58
Maybe it responds not only to faces
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可能它不只對臉孔有反應,
06:00
but to any body part.
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而是對身體任何部分都有反應。
06:02
Maybe it responds to anything human
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可能它對任何人類的、
06:05
or anything alive
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或是有生命的、
06:07
or anything round.
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或是圓形的東西都有反應。
06:08
The only way to be really sure that that region
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唯一的確認方法,
06:10
is specialized for face recognition
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證實它專門辨識人臉,
06:13
is to rule out all of those hypotheses.
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就是一一排除這些可能性。
06:15
So we spent much of the next couple of years
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所以接下來兩、三年,
06:18
scanning subjects while they looked at lots
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我們幾乎都在掃描受試者,
06:20
of different kinds of images,
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讓他們看各式各樣不同的圖片。
06:21
and we showed that that part of the brain
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結果發現,這個大腦區域
06:23
responds strongly when you look at
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只要看到是臉孔的圖像,反應都很強烈。
06:25
any images that are faces of any kind,
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06:29
and it responds much less strongly
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但是看到非臉圖像時,反應不強,
06:31
to any image you show that isn't a face,
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06:34
like some of these.
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就像下排這些。
06:35
So have we finally nailed the case
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那麼,我們是否解開了謎底?
06:37
that this region is necessary for face recognition?
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確認我們需要靠它來辨識臉孔?
06:41
No, we haven't.
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不,還不能確定。
06:42
Brain imaging can never tell you
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大腦造影技術沒辦法告訴我們
06:44
if a region is necessary for anything.
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某個大腦區域對於某種功能
是否為必要。
06:46
All you can do with brain imaging
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大腦造影只能
06:48
is watch regions turn on and off
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觀察人們有不同想法時,
大腦各區的亮、暗情況。
06:50
as people think different thoughts.
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06:52
To tell if a part of the brain is
necessary for a mental function,
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若想知道大腦某區域
是否為某種心智功能之必要,
06:55
you need to mess with it and see what happens,
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必須刺激這個區域,看看會發生什麼事。
06:58
and normally we don't get to do that.
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通常我們沒有機會這樣做。
07:00
But an amazing opportunity came about
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但是後來有一個奇妙的機緣:
07:03
very recently when a couple of colleagues of mine
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最近我的幾位同事
07:05
tested this man who has epilepsy
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測試了這位癲癇病患,
07:08
and who is shown here in his hospital bed
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這是他躺在病床上,
07:11
where he's just had electrodes placed
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醫院剛安裝了一些電極
07:12
on the surface of his brain
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在他的大腦表面,
07:14
to identify the source of his seizures.
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以便找出癲癇的病灶。
07:17
So it turned out by total chance
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很巧的是,
07:20
that two of the electrodes
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其中兩個電極
07:22
happened to be right on top of his face area.
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剛好裝在臉孔辨識區上面。
07:25
So with the patient's consent,
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在病人的同意之下,
07:27
the doctors asked him what happened
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醫生通電流刺激大腦這個區域,
然後問他有什麼感覺。
07:30
when they electrically stimulated
that part of his brain.
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07:34
Now, the patient doesn't know
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當時這位病人並不知道
07:35
where those electrodes are,
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這些電極裝在哪裡,
07:37
and he's never heard of the face area.
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也從未聽說過大腦有臉孔辨識區。
07:39
So let's watch what happens.
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讓我們看看發生了什麼事:
07:41
It's going to start with a control condition
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先從控制組開始,
07:43
that will say "Sham" nearly invisibly
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螢幕左下角會有淡紅色標示 “SHAM”,
07:45
in red in the lower left,
195
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07:47
when no current is delivered,
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表示這時沒有電流通過。
07:49
and you'll hear the neurologist speaking
to the patient first. So let's watch.
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你會先聽到神經學家對病人說話。
我們開始看:
07:53
(Video) Neurologist: Okay, just look at my face
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神經學家:好,看著我的臉,
07:55
and tell me what happens when I do this.
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然後告訴我,
當我這樣做的時候發生了什麼事。
07:59
All right?
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可以嗎?
08:00
Patient: Okay.
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病人:好。
08:02
Neurologist: One, two, three.
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神經學家:一、二、三。
(SHAM,未通電流)
08:07
Patient: Nothing.
Neurologist: Nothing? Okay.
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病人:沒事。
神經學家:沒事?好。
08:10
I'm going to do it one more time.
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我要再做一次,
08:12
Look at my face.
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看著我的臉,
08:15
One, two, three.
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一、二、三。
(通 4 毫安培電流)
08:20
Patient: You just turned into somebody else.
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病人:你剛剛變成了另外一個人!
08:23
Your face metamorphosed.
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你變臉了,
08:25
Your nose got saggy, it went to the left.
209
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你的鼻子下垂,往左偏了,
08:28
You almost looked like somebody I'd seen before,
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你看起來幾乎很像
我以前見過的某個人,
08:31
but somebody different.
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但又不是那個人。
08:34
That was a trip.
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太迷幻了!
08:36
(Laughter)
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(笑聲)
08:39
Nancy Kanwisher: So this experiment —
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所以這個實驗
08:41
(Applause) —
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(觀眾掌聲)
08:45
this experiment finally nails the case
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這個實驗終於確認
08:48
that this region of the brain is not only
217
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大腦的這個區域
08:49
selectively responsive to faces
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不只會對臉孔產生反應,
08:52
but causally involved in face perception.
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而是直接影響臉孔認知。
08:55
So I went through all of these details
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我解釋臉孔辨識區的這所有細節,
08:57
about the face region to show you what it takes
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是要讓你們了解,
08:59
to really establish that a part of the brain
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要怎樣才能確知大腦某個區域
09:02
is selectively involved in a specific mental process.
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是專門負責某項腦力活動。
09:05
Next, I'll go through much more quickly
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接下來,我會很快地介紹,
09:07
some of the other specialized regions of the brain
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我們和其他科學家發現的
大腦其他功能專區。
09:10
that we and others have found.
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2100
09:12
So to do this, I've spent a lot of time
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為了這個,上個月我常待在掃描儀內,
09:14
in the scanner over the last month
228
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09:16
so I can show you these things in my brain.
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好讓你們看看我大腦的這些區域。
09:18
So let's get started. Here's my right hemisphere.
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讓我們開始吧:
這是我的右腦。
09:21
So we're oriented like that.
You're looking at my head this way.
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掃描是從這個方向,
你們是這樣看我的大腦。
09:24
Imagine taking the skull off
232
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想像把頭殼拿掉,
09:25
and looking at the surface of the brain like that.
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然後從這裡看大腦表面。
09:27
Okay, now as you can see,
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好,正如你們所見,
09:29
the surface of the brain is all folded up.
235
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大腦表面滿是褶皺,
09:30
So that's not good. Stuff could be hidden in there.
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這樣不容易看,裡面可能還有東西,
09:32
We want to see the whole thing,
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我們想要看到大腦的全部,
09:34
so let's inflate it so we can see the whole thing.
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所以把它展開,就可以看清楚了。
09:37
Next, let's find that face area I've been talking about
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接下來,要找出剛講的臉孔辨識區,
09:40
that responds to images like these.
240
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就是對這些圖有反應的那個區域。
09:42
To see that, let's turn the brain around
241
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1519
要看到它,就把大腦轉過來,
09:43
and look on the inside surface on the bottom,
242
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看底部的內表層。
09:45
and there it is, that's my face area.
243
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找到了,這就是我的臉孔辨識區。
09:48
Just to the right of that is another region
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它的右邊,是另一個區域,
09:50
that is shown in purple
245
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標成紫色的,
09:52
that responds when you process color information,
246
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會對色彩有反應。
09:55
and near those regions are other regions
247
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另外,在這兩區附近,
09:58
that are involved in perceiving places,
248
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有些區域是跟地理認知有關。
10:00
like right now, I'm seeing
this layout of space around me
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像現在,我正在看四週的講堂空間,
10:03
and these regions in green right there
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1752
這些綠色的區域
10:05
are really active.
251
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會非常活躍,
10:06
There's another one out on the outside surface again
252
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外表層也有一個綠色的。
10:08
where there's a couple more face regions as well.
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2805
還有幾個臉孔辨識區。
10:11
Also in this vicinity
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2345
另外,這附近還有
10:14
is a region that's selectively involved
255
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1645
一個處理視覺運動的區域,
10:15
in processing visual motion,
256
615785
1936
10:17
like these moving dots here,
257
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1504
就像這些運動的小點,
10:19
and that's in yellow at the bottom of the brain,
258
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就是在大腦底部黃色的這個區域。
10:21
and near that is a region that responds
259
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3168
旁邊的這個區域,
會在看到身體部位時產生反應,
10:25
when you look at images of bodies and body parts
260
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2897
10:27
like these, and that region is shown in lime green
261
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2745
像這些圖片,
就是在大腦底部亮綠色的那個區域。
10:30
at the bottom of the brain.
262
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2003
10:32
Now all these regions I've shown you so far
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到目前為止,我給你們看的所有區域,
10:35
are involved in specific aspects of visual perception.
264
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4432
都是跟視覺的特定面向有關。
10:39
Do we also have specialized brain regions
265
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2148
那麼,我們是否有大腦專區
10:41
for other senses, like hearing?
266
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負責其他感覺呢?
例如聽覺?
10:44
Yes, we do. So if we turn the brain around a little bit,
267
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3037
有的。
如果把大腦再轉過來一點,
10:47
here's a region in dark blue
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2401
這裡有一塊深藍色區域,
10:50
that we reported just a couple of months ago,
269
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2346
是我們在幾個月前才確認的,
10:52
and this region responds strongly
270
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1634
聽到有音高的聲音時,這區會強烈反應,
10:54
when you hear sounds with pitch, like these.
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3429
像這些聲音:
10:57
(Sirens)
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(警報聲)
10:59
(Cello music)
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2081
(大提琴音樂)
11:01
(Doorbell)
274
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1917
(門鈴)
11:03
In contrast, that same region
does not respond strongly
275
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3608
但是,同樣這個區域,
聽到無明顯音高的熟悉聲音時,
卻反應微弱,
11:07
when you hear perfectly familiar sounds
276
667348
1562
11:08
that don't have a clear pitch, like these.
277
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2362
像這些聲音:
11:11
(Chomping)
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(拍手聲)
11:13
(Drum roll)
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2200
(鼓點聲)
11:15
(Toilet flushing)
280
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2767
(馬桶沖水聲)
11:18
Okay. Next to the pitch region
281
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2498
好,音高區的旁邊,
11:21
is another set of regions that
are selectively responsive
282
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2474
有另一組區域,
11:23
when you hear the sounds of speech.
283
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2765
會對講話聲有反應。
11:26
Okay, now let's look at these same regions.
284
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好,我們來看看同樣這些區域,
11:28
In my left hemisphere, there's a similar arrangement —
285
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2468
在我的左腦,也有相似的區域分佈,
11:30
not identical, but similar —
286
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1473
不完全相同,但是十分相似。
11:32
and most of the same regions are in here,
287
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2209
同樣的這些區域
幾乎也都在左腦裡,
11:34
albeit sometimes different in size.
288
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2002
只是大小可能不一樣。
11:36
Now, everything I've shown you so far
289
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2014
到現在為止,我介紹的所有區域,
11:38
are regions that are involved in
different aspects of perception,
290
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3026
都跟知覺的不同面向有關,
11:41
vision and hearing.
291
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1833
視覺跟聽覺。
11:43
Do we also have specialized brain regions
292
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1660
那,大腦有沒有專區
11:44
for really fancy, complicated mental processes?
293
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3435
負責很高階、複雜的心智活動呢?
11:48
Yes, we do.
294
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1429
有的。
11:49
So here in pink are my language regions.
295
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3389
這些粉紅色塊是我的語言區。
11:53
So it's been known for a very long time
296
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1428
科學家很早就發現,
11:54
that that general vicinity of the brain
297
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2035
大腦的這些地帶
11:56
is involved in processing language,
298
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2193
是語言處理區。
11:58
but we showed very recently
299
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1732
但我們的最新研究顯示,
12:00
that these pink regions
300
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1710
這些粉紅區域的反應
12:02
respond extremely selectively.
301
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2205
是非常有選擇性。
12:04
They respond when you understand
the meaning of a sentence,
302
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2812
當你了解一個句子的意思時,反應很強,
12:07
but not when you do other complex mental things,
303
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2838
但是對其他複雜的腦力活動沒有反應,
12:10
like mental arithmetic
304
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2179
例如,心算,
12:12
or holding information in memory
305
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2396
或記憶訊息,
12:14
or appreciating the complex structure
306
734751
2655
或欣賞一段音樂的複雜結構。
12:17
in a piece of music.
307
737406
2284
12:21
The most amazing region that's been found yet
308
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2889
目前所發現最令人稱奇的區域,
12:24
is this one right here in turquoise.
309
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3307
是藍綠色的這一塊,
12:27
This region responds
310
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2190
當你猜測他人心思時,這一區會很活躍。
12:30
when you think about what another person is thinking.
311
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4268
12:34
So that may seem crazy,
312
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1644
聽起來很詭異,
12:35
but actually, we humans do this all the time.
313
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3868
但其實,我們人類經常做這件事,
12:39
You're doing this when you realize
314
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2193
比方說,當你想到
12:42
that your partner is going to be worried
315
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1631
你的伴侶會很擔憂,
12:43
if you don't call home to say you're running late.
316
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2507
如果你會晚回家卻沒打電話。
12:46
I'm doing this with that region of my brain right now
317
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3469
現在我大腦的那一區也在這樣做,
12:49
when I realize that you guys
318
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2281
就在我意識到
你們可能正在猜測
12:51
are probably now wondering about
319
771911
1598
12:53
all that gray, uncharted territory in the brain,
320
773509
2547
大腦中那些未知的灰色區域,
12:56
and what's up with that?
321
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1964
想知道它們是做什麼的?
12:58
Well, I'm wondering about that too,
322
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1685
其實,我自己也很想知道,
12:59
and we're running a bunch of
experiments in my lab right now
323
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2395
我的實驗室團隊正在進行很多實驗,
13:02
to try to find a number of other
324
782100
2013
想找到其他一些
13:04
possible specializations in the brain
325
784113
2032
可能存在的大腦專區,
13:06
for other very specific mental functions.
326
786145
3368
負責其他特定心智功能。
但是我想強調,
13:09
But importantly, I don't think we have
327
789513
2621
不是每個重要的心智功能
都有對應的大腦專區,
13:12
specializations in the brain
328
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1564
13:13
for every important mental function,
329
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2746
13:16
even mental functions that may be critical for survival.
330
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3409
即使是攸關生存的重要心智功能。
13:19
In fact, a few years ago,
331
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2102
事實上,幾年前,
13:21
there was a scientist in my lab
332
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1117
我實驗室有一位科學家,
13:23
who became quite convinced
333
803072
1409
他十分肯定
13:24
that he'd found a brain region
334
804481
1749
自己發現了辨識食物的大腦專區,
13:26
for detecting food,
335
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1912
13:28
and it responded really strongly in the scanner
336
808142
1918
當人們看到這些圖像時,反應很強烈。
13:30
when people looked at images like this.
337
810060
2728
13:32
And further, he found a similar response
338
812788
2912
不但如此,
他在 12 位受試者中發現,
有 10 位都在相似區域有類似反應。
13:35
in more or less the same location
339
815700
1939
13:37
in 10 out of 12 subjects.
340
817639
2001
13:39
So he was pretty stoked,
341
819640
2294
這發現讓他非常振奮,
13:41
and he was running around the lab
342
821934
1260
在實驗室滿場跑,
13:43
telling everyone that he was going to go on "Oprah"
343
823194
2002
告訴每個人他要上電視《毆普拉》受訪,
13:45
with his big discovery.
344
825196
2018
分享他的大發現了!
13:47
But then he devised the critical test:
345
827214
3022
但接下來他設計了一個關鍵的測試:
13:50
He showed subjects images of food like this
346
830236
3183
給受試者看像這樣的食物圖片,
13:53
and compared them to images with very similar
347
833419
2741
對照另一組顏色、形狀都很相似
13:56
color and shape, but that weren't food, like these.
348
836160
3810
但並非食物的圖片,就像這些,
13:59
And his region responded the same
349
839970
2131
結果這個大腦區域
對兩組圖片反應都一樣,
14:02
to both sets of images.
350
842101
1949
14:04
So it wasn't a food area,
351
844050
1327
所以它並不是食物專區,
14:05
it was just a region that liked colors and shapes.
352
845377
2771
只是一個喜歡顏色和形狀的區域。
14:08
So much for "Oprah."
353
848148
2561
上《毆普拉》的美夢就泡湯了。
14:12
But then the question, of course, is,
354
852483
2225
那麼接下來的問題當然是,
14:14
how do we process all this other stuff
355
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2126
人類是如何辦到
14:16
that we don't have specialized brain regions for?
356
856834
2970
其他那些沒有大腦專區負責的事呢?
14:19
Well, I think the answer is that in addition
357
859804
1811
我認為答案是,
除了今天介紹的這些高度分工專區,
14:21
to these highly specialized components
that I've been describing,
358
861615
3554
14:25
we also have a lot of very general-
purpose machinery in our heads
359
865169
3679
大腦裡還有許多通用的機制,
14:28
that enables us to tackle
360
868848
1494
使我們能夠處理遇到的任何問題。
14:30
whatever problem comes along.
361
870342
2106
14:32
In fact, we've shown recently that
362
872448
2055
事實上,我們最新的研究顯示,
14:34
these regions here in white
363
874503
2068
這些白色區域,
14:36
respond whenever you do any difficult mental task
364
876571
3411
在你做任何困難任務時都有反應,
14:39
at all —
365
879982
1101
14:41
well, of the seven that we've tested.
366
881083
3571
至少對我們設計的全部七個任務
都有反應。
14:44
So each of the brain regions that I've described
367
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我今天介紹的每一個大腦專區,
14:46
to you today
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14:48
is present in approximately the same location
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在每個正常大腦中,位置幾乎都一樣。
14:50
in every normal subject.
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14:52
I could take any of you,
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我可以隨意挑選你們其中一人,
14:54
pop you in the scanner,
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送進掃描儀,
14:55
and find each of those regions in your brain,
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找出在你大腦中的這些專區,
14:57
and it would look a lot like my brain,
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結果會和我大腦的分佈很像,
14:59
although the regions would be slightly different
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儘管精確位置和大小可能稍有差異。
15:01
in their exact location and in their size.
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15:05
What's important to me about this work
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對我而言,這項工作的重要性,
15:07
is not the particular locations of these brain regions,
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並不在於這些大腦專區的特定位置,
15:10
but the simple fact that we have
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而是發現,
15:13
selective, specific components of mind and brain
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大腦和心智確實有非常專屬的單元。
15:15
in the first place.
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15:17
I mean, it could have been otherwise.
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意思是,當初可能有不一樣的發現,
15:19
The brain could have been a single,
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人腦可能是個單一、通用的處理器,
15:21
general-purpose processor,
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15:23
more like a kitchen knife
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像一把菜刀,
15:24
than a Swiss Army knife.
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而不是一把瑞士刀。
15:26
Instead, what brain imaging has delivered
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然而,腦造影技術呈現了
15:29
is this rich and interesting picture of the human mind.
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豐富奧妙的人腦圖像。
15:33
So we have this picture of very general-purpose
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所以我們看到整個大腦是
15:35
machinery in our heads
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一部萬用機器,
15:37
in addition to this surprising array
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加上令人驚奇的許多
15:39
of very specialized components.
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高度分工的專用元件。
15:43
It's early days in this enterprise.
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腦神經科學還在萌芽階段,
15:45
We've painted only the first brushstrokes
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人類大腦神經圖像
我們只畫了剛開始的幾筆,
15:48
in our neural portrait of the human mind.
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15:51
The most fundamental questions remain unanswered.
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最根本的一些問題仍無解答。
15:54
So for example, what does each
of these regions do exactly?
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例如,
今天講的每個區域到底是做什麼的?
15:58
Why do we need three face areas
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為什麼我們需要三個臉孔區域?
16:00
and three place areas,
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和三個地理區域?
16:02
and what's the division of labor between them?
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它們之間如何分工?
16:04
Second, how are all these things
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第二,大腦中這所有的東西
16:07
connected in the brain?
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如何互相聯繫?
16:09
With diffusion imaging,
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利用擴散造影,
16:10
you can trace bundles of neurons
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可以追蹤連接大腦不同部分的
多束神經元,
16:13
that connect to different parts of the brain,
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16:15
and with this method shown here,
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你現在看到的這個方法,
16:17
you can trace the connections of
individual neurons in the brain,
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可以追蹤「個別神經元」之間的聯繫,
16:20
potentially someday giving us a wiring diagram
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有朝一日,或許能畫出完整的人腦線路圖。
16:23
of the entire human brain.
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16:25
Third, how does all of this
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第三,這整個超高系統結構
16:27
very systematic structure get built,
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是如何建立起來的?
16:30
both over development in childhood
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童年時期的發展對它有什麼影響?
16:33
and over the evolution of our species?
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物種演化對它又有什麼影響?
16:36
To address questions like that,
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為了解決像這類的問題,
16:38
scientists are now scanning
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科學家們已開始掃描其他動物,
16:40
other species of animals,
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16:42
and they're also scanning human infants.
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也掃描人類嬰兒。
16:48
Many people justify the high
cost of neuroscience research
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許多人認為腦神經學
值得斥資重金研究,
16:52
by pointing out that it may help us someday
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認為將來可能會幫助我們
16:55
to treat brain disorders like Alzheimer's and autism.
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治療大腦疾病,
如老年癡呆症和自閉症。
16:58
That's a hugely important goal,
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這個目標極其重要,
17:00
and I'd be thrilled if any of my work contributed to it,
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若我的研究能有助此目標,
我會高興得不得了。
17:03
but fixing things that are broken in the world
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但修復世間的破碎與敗壞,
17:06
is not the only thing that's worth doing.
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不是唯一值得做的事。
17:09
The effort to understand the human mind and brain
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認識人類心智和大腦
同樣值得追求,
17:12
is worthwhile even if it never led to the treatment
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即使這些努力沒能治癒任何疾病。
17:15
of a single disease.
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17:17
What could be more thrilling
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有什麼比了解人類生命經驗的基礎
更令人振奮呢?
17:19
than to understand the fundamental mechanisms
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17:22
that underlie human experience,
430
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17:24
to understand, in essence, who we are?
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從本質上,了解「我們是誰?」
17:27
This is, I think, the greatest scientific quest
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我想,
這是人類永遠最重要的科學探索。
17:31
of all time.
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投影片:感謝研究團隊過去與現在成員
(觀眾掌聲)
17:34
(Applause)
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