the age of genomics.

我們生在一個偉大的時代

Your genome is the entire sequence of your DNA.

一個染色體組的時代。

Your sequence and mine are slightly different.

你的染色體是你所有的DNA序列

That's why we look different.

你的序列和我的有些不同

I've got brown eyes;

因此我們長得不一樣

you might have blue or gray.

我的眼睛是褐色的

But it's not just skin-deep.

你的可能是藍或灰

The headlines tell us

但這不只是表面

that genes can give us scary diseases,

新聞標題告訴我們

maybe even shape our personality,

基因裡可能隱藏著遺傳疾病

or give us mental disorders.

甚至影響我們的個性

Our genes seem to have

或給我們帶來精神異常

awesome power over our destinies.

我們的基因似乎

And yet, I would like to think

對我們的命運有著極大的影響力

that I am more than my genes.

仍然﹐我希望

What do you guys think?

我不只是我的基因

Are you more than your genes?

你覺得呢﹖

(Audience: Yes.) Yes?

你不只是你的基因吧﹖

I think some people agree with me.

(觀眾﹕不只) 是嗎﹖

I think we should make a statement.

我想觀眾中有些人同意我的說法

I think we should say it all together.

我認為我們應該宣示一下

All right: "I'm more than my genes" -- all together.

我認為我們應該一起宣示

Everybody: I am more than my genes.

來吧﹕我不只是我的基因 -- 一起來

(Cheering)

眾人﹕我不只是我的基因

Sebastian Seung: What am I?

(歡呼)

(Laughter)

那我是什麼﹖

I am my connectome.

(笑聲)

Now, since you guys are really great,

我是我的聯結體。

maybe you can humor me and say this all together too.

你們實在太棒了

(Laughter)

為了讓我開心﹐或許我們可以再宣示一次﹖

Right. All together now.

(笑聲)

Everybody: I am my connectome.

好﹐一起來

SS: That sounded great.

眾人﹕我是我的聯結體。

You know, you guys are so great, you don't even know what a connectome is,

這實在太棒了。

and you're willing to play along with me.

你們實在太棒了﹐你們甚至不知道聯結體是什麼

I could just go home now.

配合度這麼高

Well, so far only one connectome is known,

或許我現在就可以走了

that of this tiny worm.

現在﹐我們只知道一個聯結體

Its modest nervous system

在這個小蟲裡

consists of just 300 neurons.

最小的神經系統

And in the 1970s and '80s,

裡面有300個神經元

a team of scientists

在1970和80年代

mapped all 7,000 connections

有一組科學家

between the neurons.

畫出神經元中間

In this diagram, every node is a neuron,

的七千個聯繫

and every line is a connection.

這個圖表裡的每個結都是一個神經元

This is the connectome

每條線都是一個聯結。

of the worm C. elegans.

這就是秀麗隱桿線蟲的

Your connectome is far more complex than this

聯結體

because your brain

你的聯結體比這個複雜多了

contains 100 billion neurons

因為你的腦子裡

and 10,000 times as many connections.

有一百億個神經元

There's a diagram like this for your brain,

以及一萬倍的聯結體

but there's no way it would fit on this slide.

你的腦子也能做成像這樣的圖表

Your connectome contains one million times more connections

只是不可能放得進這張投影片

than your genome has letters.

你聯結體的聯結是

That's a lot of information.

基因體編碼的一百萬倍

What's in that information?

裡面有很多資料

We don't know for sure, but there are theories.

這些資料裡包含了什麼﹖

Since the 19th century, neuroscientists have speculated

我們還不能確定﹐但有一些學說

that maybe your memories --

從十九世紀以來﹐神經科學家推測

the information that makes you, you --

你的記憶 -

maybe your memories are stored

那些讓你之所以為你的資料 -

in the connections between your brain's neurons.

說不定你的記憶就儲存在

And perhaps other aspects of your personal identity --

腦子裡神經元的聯結裡

maybe your personality and your intellect --

或者你其他的個人特性

maybe they're also encoded

你的個性和你的思維方式

in the connections between your neurons.

說不定它們都寫在

And so now you can see why I proposed this hypothesis:

你的神經元的聯結裡

I am my connectome.

現在你可以了解為什麼我要提出這個假設﹕

I didn't ask you to chant it because it's true;

我就是我的聯結體。

I just want you to remember it.

我要你和我一起吟誦不是因為它是真的

And in fact, we don't know if this hypothesis is correct,

我只是希望你記住它

because we have never had technologies

事實上﹐我們不知道這個假設是否正確

powerful enough to test it.

因為我們從來沒有如此強大的科技

Finding that worm connectome

足以測試這個假設

took over a dozen years of tedious labor.

找到這個線蟲的聯結體

And to find the connectomes of brains more like our own,

花了12年的努力

we need more sophisticated technologies, that are automated,

要找到我們腦子裡的這些聯結體

that will speed up the process of finding connectomes.

我們需要更精密的自動儀器

And in the next few minutes, I'll tell you about some of these technologies,

才能加速我們找尋聯結體的速度。

which are currently under development

接下來的幾分鐘﹐我會告訴你們這些

in my lab and the labs of my collaborators.

在我和我的合作者的實驗室裡

Now you've probably seen pictures of neurons before.

發展中的新科技。

You can recognize them instantly

你可能看過神經元的圖片

by their fantastic shapes.

你可以從它們的姿態裡

They extend long and delicate branches,

輕易的認出它來

and in short, they look like trees.

它們延伸著長長的精密分支

But this is just a single neuron.

簡單來說﹐看上去就像棵樹

In order to find connectomes,

但這只是一個神經元

we have to see all the neurons at the same time.

如果我們要找尋聯結體

So let's meet Bobby Kasthuri,

我們需要同時看見所有神經元

who works in the laboratory of Jeff Lichtman

讓我們認識這位Bobby Kasthuri

at Harvard University.

他在哈佛 Jeff Lichtman 實驗室

Bobby is holding fantastically thin slices

裡面工作

of a mouse brain.

Bobby 手握著一片奇妙的

And we're zooming in by a factor of 100,000 times

老鼠腦。

to obtain the resolution,

讓我們放大十萬倍

so that we can see the branches of neurons all at the same time.

得到一個更清晰的分辨率

Except, you still may not really recognize them,

讓我們一次看見神經元的所有分支

and that's because we have to work in three dimensions.

除了﹐你可能認不出它來

If we take many images of many slices of the brain

因為我們需要在三維度裡看

and stack them up,

讓我們把一片片的腦部圖片

we get a three-dimensional image.

堆起來

And still, you may not see the branches.

我們就得到了這個3D圖像

So we start at the top,

但是你還是看不到這些分支

and we color in the cross-section of one branch in red,

於是我們從上面

and we do that for the next slice

把橫斷面裡的分支塗成紅色

and for the next slice.

然後再塗下一片

And we keep on doing that,

再下一片

slice after slice.

我們一直這樣做

If we continue through the entire stack,

一片又一片

we can reconstruct the three-dimensional shape

直到我們把整堆都塗完

of a small fragment of a branch of a neuron.

我們就可以在3D形狀裡重現

And we can do that for another neuron in green.

神經元分支的一小部份

And you can see that the green neuron touches the red neuron

我們可以把另一個神經元涂成綠色

at two locations,

我們可以看到綠色和紅色神經元

and these are what are called synapses.

在兩個地方接觸

Let's zoom in on one synapse,

這就是所謂的突觸(synapses)

and keep your eyes on the interior of the green neuron.

讓我們放大這個突觸

You should see small circles --

繼續看著綠色神經元的內部

these are called vesicles.

你會看到小小的圈

They contain a molecule know as a neurotransmitter.

這些就是突觸小泡(囊泡)

And so when the green neuron wants to communicate,

裡面有叫神經傳遞素的分子

it wants to send a message to the red neuron,

當綠色神經元想和紅色神經元溝通

it spits out neurotransmitter.

傳遞訊息的時候

At the synapse, the two neurons

它就從突觸吐出神經傳遞素

are said to be connected

兩個神經元

like two friends talking on the telephone.

就這樣聯繫

So you see how to find a synapse.

像兩個朋友講電話一樣

How can we find an entire connectome?

這就是找到突觸的方法

Well, we take this three-dimensional stack of images

但要怎麼找到整個聯結體呢

and treat it as a gigantic three-dimensional coloring book.

我們把這堆層層疊起的3D畫面

We color every neuron in, in a different color,

把它變成一個超大型的3D塗色簿

and then we look through all of the images,

把所有神經元涂成不同顏色

find the synapses

看過所有切片圖

and note the colors of the two neurons involved in each synapse.

找到突觸

If we can do that throughout all the images,

然後在記錄參與突觸的兩個神經元

we could find a connectome.

如果我們可以這樣處理所有圖片

Now, at this point,

就可以找到一個聯結體

you've learned the basics of neurons and synapses.

目前為止

And so I think we're ready to tackle

你們已經學到了神經元和突觸的基礎

one of the most important questions in neuroscience:

我想我們已經可以處理

how are the brains of men and women different?

神經科學裡最重要的問題之一﹕

(Laughter)

男人和女人的大腦有什麼不同﹖

According to this self-help book,

(笑聲)

guys brains are like waffles;

從這本勵志書裡看來

they keep their lives compartmentalized in boxes.

男人的大腦像鬆餅

Girls' brains are like spaghetti;

把生活分門別類放在小格子裡

everything in their life is connected to everything else.

女人的大腦則像意大利麵

(Laughter)

人生裡的每件事都習習相關

You guys are laughing,

(笑聲)

but you know, this book changed my life.

你們現在在笑

(Laughter)

但這本書改變了我的生命

But seriously, what's wrong with this?

(笑聲)

You already know enough to tell me -- what's wrong with this statement?

但說真的﹐它錯在哪裡﹖

It doesn't matter whether you're a guy or girl,

你們已經有能力可以告訴我﹐這句話錯在哪裡

everyone's brains are like spaghetti.

無論你是男人還是女人

Or maybe really, really fine capellini with branches.

每個人的大腦都是意大利麵

Just as one strand of spaghetti

或是﹐加上分支的超細天使髮麵

contacts many other strands on your plate,

就像在你盤子裡的一條意大利麵

one neuron touches many other neurons

碰觸其它意大利麵一樣

through their entangled branches.

一個神經元會用它們糾纏的分支

One neuron can be connected to so many other neurons,

觸碰許多其它神經元

because there can be synapses

一個神經元可以和許多其它神經元連接

at these points of contact.

因為在這些聯結點

By now, you might have sort of lost perspective

可以有許多突觸

on how large this cube of brain tissue actually is.

現在你可能已經忘記

And so let's do a series of comparisons to show you.

這塊腦尺度究竟有多小

I assure you, this is very tiny. It's just six microns on a side.

我們來比較一下

So, here's how it stacks up against an entire neuron.

這真的很小﹐只有六微米(百萬分之一米)

And you can tell that, really, only the smallest fragments of branches

面對整條神經元又是怎樣呢

are contained inside this cube.

你可以發現﹐這個方塊

And a neuron, well, that's smaller than brain.

只是這個分支其中的一小小塊

And that's just a mouse brain --

而神經元﹐當然比腦還小

it's a lot smaller than a human brain.

而這甚至只是老鼠的腦

So when show my friends this,

比人腦還小很多

sometimes they've told me,

於是當我給朋友看這些的時候

"You know, Sebastian, you should just give up.

他們會告訴我

Neuroscience is hopeless."

“Sebastian﹐我想你放棄好了。

Because if you look at a brain with your naked eye,

神經科學簡直無可救藥。”

you don't really see how complex it is,

因為當你用肉眼看大腦時

but when you use a microscope,

你不知道它到底有多麼複雜

finally the hidden complexity is revealed.

但當你把它放在顯微鏡下

In the 17th century,

這些隱藏的複雜性就顯露出來了。

the mathematician and philosopher, Blaise Pascal,

在十七世紀

wrote of his dread of the infinite,

法國哲學家和數學家巴斯卡

his feeling of insignificance

寫下他對無限的恐懼

at contemplating the vast reaches of outer space.

當他思考外太空時

And, as a scientist,

感到自己是如何的微不足道

I'm not supposed to talk about my feelings --

身為科學家

too much information, professor.

我不應該談論我的感受

(Laughter)

教授﹐我真的不想知道

But may I?

(笑聲)

(Laughter)

我...... 可以嗎﹖

(Applause)

(笑聲)

I feel curiosity,

(掌聲)

and I feel wonder,

我感到好奇

but at times I have also felt despair.

我感到驚嘆

Why did I choose to study

但有時我也感到絕望

this organ that is so awesome in its complexity

為什麼我要選擇學習

that it might well be infinite?

這樣一個複雜到不可思議

It's absurd.

有可能接近無限的器官﹖

How could we even dare to think

這太荒謬了

that we might ever understand this?

我們怎麼敢妄想

And yet, I persist in this quixotic endeavor.

我們有可能可以理解它呢﹖

And indeed, these days I harbor new hopes.

但﹐我仍然想踏上這唐吉訶德式的旅程

Someday,

最近﹐我有了新的希望

a fleet of microscopes will capture

或許某天

every neuron and every synapse

某種顯微鏡能捕捉

in a vast database of images.

巨大圖片資料庫裡的

And some day, artificially intelligent supercomputers

每一個神經元和突觸

will analyze the images without human assistance

有這麼一天﹐一個人工智慧的超級電腦

to summarize them in a connectome.

能在無人操作的狀況下分析這些圖像

I do not know, but I hope that I will live to see that day,

並把它們總結成一個聯結體

because finding an entire human connectome

我不知道能不能﹐但我希望我能看到這一天

is one of the greatest technological challenges of all time.

因為找出人類的所有聯結體

It will take the work of generations to succeed.

是科技史上最大的挑戰之一

At the present time, my collaborators and I,

可能要幾個世代才能成功

what we're aiming for is much more modest --

目前﹐我和我的夥伴

just to find partial connectomes

我們的目標較為微小

of tiny chunks of mouse and human brain.

不過是在鼠腦和人腦間

But even that will be enough for the first tests of this hypothesis

找到部份的聯結體

that I am my connectome.

但就算只是這樣﹐也足以實驗“我就是我的聯結體“

For now, let me try to convince you of the plausibility of this hypothesis,

這個假設

that it's actually worth taking seriously.

現在我只是想說服你們﹐這個假設有它的可信度

As you grow during childhood

它是值得被認真對待的

and age during adulthood,

在你的成長過程

your personal identity changes slowly.

不同的經歷

Likewise, every connectome

你對自己的身份認同也逐漸改變

changes over time.

同樣地﹐每個聯結體

What kinds of changes happen?

也隨著時間改變

Well, neurons, like trees,

怎樣的改變呢﹖

can grow new branches,

神經元﹐就像樹一樣

and they can lose old ones.

可以長出新的枝幹

Synapses can be created,

也可以失去一些老枝幹

and they can be eliminated.

突觸可以被創造

And synapses can grow larger,

也可以被淘汰

and they can grow smaller.

突觸可以長大

Second question:

也可以變小

what causes these changes?

第二個問題是﹕

Well, it's true.

這些改變是從哪裡來的﹖

To some extent, they are programmed by your genes.

沒錯

But that's not the whole story,

某種程度而言﹐它們寫在你的基因裡

because there are signals, electrical signals,

但那不是全部

that travel along the branches of neurons

因為有訊號﹐電位訊號

and chemical signals

在神經元枝幹裡運行

that jump across from branch to branch.

還有化學訊號

These signals are called neural activity.

從枝幹跳往枝幹

And there's a lot of evidence

這些訊號就叫神經活動

that neural activity

有很多證據

is encoding our thoughts, feelings and perceptions,

神經活動

our mental experiences.

寫就了我們的想法﹐感覺和感知