about how we can change our brains

我今天想談談

and our society.

人類能如何改變我們的頭腦

Meet Joe.

與我們的社會。

Joe's 32 years old and a murderer.

這位是喬。

I met Joe 13 years ago on the lifer wing

喬 32 歲，是殺人兇手。

at Wormwood Scrubs high-security prison in London.

13 年前，我在無期徒刑的牢房認識他，

I'd like you to imagine this place.

位於倫敦高戒備的苦艾監獄裡。

It looks and feels like it sounds:

請你們想像這個地方。

Wormwood Scrubs.

看起來和感覺起來就像它的名字：

Built at the end of the Victorian Era

苦艾監獄 （Wormwood Scrubs 有洗刷悔恨之意）。

by the inmates themselves,

在維多利亞時代末期時

it is where England's most dangerous prisoners are kept.

完全由囚犯建造而成，

These individuals have committed acts

那裡監禁著英國最危險的犯人。

of unspeakable evil.

這些人都犯了

And I was there to study their brains.

難以言喻的滔天大罪。

I was part of a team of researchers

我在那裡研究他們的腦。

from University College London,

我是倫敦大學學院研究團隊的成員之一，

on a grant from the U.K. department of health.

這計畫由英國健康衛生署補助。

My task was to study a group of inmates

我的任務是研究一群受刑人，

who had been clinically diagnosed as psychopaths.

他們被臨床診斷為精神病患者。

That meant they were the most

意即他們是所有受刑人中 最為冷酷無情，且最具攻擊性的罪犯。

callous and the most aggressive

他們行為的根源是什麼？

of the entire prison population.

是否有神經因素引發他們的疾病？

What lay at the root of their behavior?

如果有神經因素的話，

Was there a neurological cause for their condition?

我們能不能找到治療方式？

And if there was a neurological cause,

我想談變化，尤其是情緒變化。

could we find a cure?

成長期間，我總是對

So I'd like to speak about change, and especially about emotional change.

人們改變的方式感興趣。

Growing up, I was always intrigued

我的母親是臨床心理學家，

by how people change.

晚上她偶爾會在家看診。

My mother, a clinical psychotherapist,

她會關上通往客廳的門，

would occasionally see patients at home

我就會開始想像

in the evening.

房裡發生了神奇的事情。

She would shut the door to the living room,

在五歲或六歲時，

and I imagined

我會穿著睡衣偷跑到客廳，

magical things happened in that room.

將耳朵貼在門上，坐在外頭。

At the age of five or six

我睡著了不止一次，

I would creep up in my pajamas

在療程結束後， 他們得把我向外推才能出來。

and sit outside with my ear glued to the door.

我想那大概就是

On more than one occasion, I fell asleep

我首次踏入苦艾監獄

and they had to push me out of the way

安全面談室的原因。

at the end of the session.

喬坐在鐵桌的對面，

And I suppose that's how I found myself

不發一語地看著我到來。

walking into the secure interview room

典獄長看來也一樣冷淡，

on my first day at Wormwood Scrubs.

他說：「有任何問題就按紅色警鈴，

Joe sat across a steel table

我們會儘快趕到。」

and greeted me with this blank expression.

（笑聲）

The prison warden, looking equally indifferent,

我坐下。

said, "Any trouble, just press the red buzzer,

沉重的金屬門在我身後關上。

and we'll be around as soon as we can."

我擡頭看著紅色警鈴，

(Laughter)

遠在另一頭，喬身後的牆上。

I sat down.

（笑聲）

The heavy metal door slammed shut behind me.

我看著喬。

I looked up at the red buzzer

也許他察覺了我的擔心，

far behind Joe on the opposite wall.

便靠向前，

(Laughter)

儘可能地安慰我說：

I looked at Joe.

「噢，別在意警鈴了，

Perhaps detecting my concern,

那根本就壞啦。」

he leaned forward, and said,

（笑聲）

as reassuringly as he could,

隨後幾個月，

"Ah, don't worry about the buzzer,

我們檢測喬和他的獄友，

it doesn't work anyway."

主要針對他們

(Laughter)

分類各種情緒圖片的能力。

Over the subsequent months,

接著觀察他們對那些情緒的身體反應。

we tested Joe and his fellow inmates,

舉例來說，我們大部分

looking specifically at their ability

見到像這樣有人看似傷心的圖片，

to categorize different images of emotion.

都會立即有輕微、

And we looked at their physical response

明顯的身體反應：

to those emotions.

心跳加快、開始流汗。

So, for example, when most of us look

我們研究中的精神病患能

at a picture like this of somebody looking sad,

正確地敘述這些圖片，

we instantly have a slight,

但是他們卻無法表現出應有的情緒。

measurable physical response:

他們沒有身體反應。

increased heart rate, sweating of the skin.

彷彿他們認得文字，

Whilst the psychopaths in our study were able

卻無法同理其中蘊含的意義。

to describe the pictures accurately,

因此我們想進一步探討這點，

they failed to show the emotions required.

運用核磁共振造影 (MRI) 取得他們腦部的圖像。

They failed to show a physical response.

結果發現這不是項簡單的任務。

It was as though they knew the words

想像你得運送一批

but not the music of empathy.

戴著手銬、腳鐐的精神病患

So we wanted to look closer at this

穿越倫敦中心，

to use MRI to image their brains.

而且還在尖鋒時間，

That turned out to be not such an easy task.

且為了將他們每個人 放進核磁共振造影機，

Imagine transporting a collection

你得移除所有金屬物品，

of clinical psychopaths across central London

包括手銬和腳鐐，

in shackles and handcuffs

還有所有的打洞、體環。

in rush hour,

一段時間後，我們有了個試驗的答案。

and in order to place each of them in an MRI scanner,

這些人不只是悲慘童年的受害者，

you have to remove all metal objects,

他們還有別的問題。

including shackles and handcuffs,

像喬這種人腦部的某個區域有缺陷，

and, as I learned, all body piercings.

這個部位稱為杏仁核。

After some time, however, we had a tentative answer.

杏仁核是一種杏仁形的器官，

These individuals were not just the victims

深藏在大腦的每個半球中，

of a troubled childhood.

被視為感受同理心的關鍵。

There was something else.

一般來說，某人越有同情心，

People like Joe have a deficit in a brain area

他的杏仁核就越大且越活躍。

called the amygdala.

囚犯的杏仁核有缺陷，

The amygdala is an almond-shaped organ

可能會導致他們缺乏同理心，

deep within each of the hemispheres of the brain.

並做出不道德的行為。

It is thought to be key to the experience of empathy.

那麼，讓我們退後一步來看。

Normally, the more empathic a person is,

一般來說，養成道德行為

the larger and more active their amygdala is.

只是成長的一部分，

Our population of inmates

就像學習說話一樣。

had a deficient amygdala,

在六個月大時，幾乎每個人

which likely led to their lack of empathy

都能辨別東西是否有生命。

and to their immoral behavior.

在一歲大時，

So let's take a step back.

大部分孩童都能模仿

Normally, acquiring moral behavior

其他人有意義的行為。

is simply part of growing up,

例如，你的母親舉起雙手做伸展，

like learning to speak.

你就會模仿她的動作。

At the age of six months, virtually every one of us

一開始不會太完美。

is able to differentiate between animate and inanimate objects.

我記得堂妹莎夏

At the age of 12 months,

在兩歲時

most children are able to imitate

就能快速翻閱繪本，

the purposeful actions of others.

舔一根手指，然後用另一隻手換頁，

So for example, your mother raises her hands

舔一根手指，然後用另一隻手換頁。

to stretch, and you imitate her behavior.

（笑聲）

At first, this isn't perfect.

漸漸地，我們建立起社會腦的基礎，

I remember my cousin Sasha,

因此我們到三、四歲的時候，

two years old at the time,

大部分的孩童，並非全部，

looking through a picture book

都已經能理解別人的意圖，

and licking one finger and flicking the page with the other hand,

這是另一種同理的前提。

licking one finger and flicking the page with the other hand.

這種發展過程舉世皆然，

(Laughter)

不論你住在世界何處，

Bit by bit, we build the foundations of the social brain

或是身在哪一種文化，

so that by the time we're three, four years old,

都強烈表示

most children, not all,

道德行為的基礎是與生俱來的。

have acquired the ability to understand

如果你懷疑這件事，

the intentions of others,

只要試一件事，我試過了，

another prerequisite for empathy.

不要遵守你對四歲孩童許下的承諾。

The fact that this developmental progression

你會發現四歲孩童的心智

is universal,

一點也不天真。

irrespective of where you live in the world

他們就像是把瑞士刀，

or which culture you inhabit,

在成長過程中

strongly suggests that the foundations

用固定的心理模組精細打造，

of moral behavior are inborn.

而且對公平的感受十分敏銳。

If you doubt this,

年幼時期至關重要。

try, as I've done, to renege on a promise you've made

童年期似乎是千載難逢的良機，

to a four-year-old.

在那之後

You will find that the mind of a four-year old

要掌握道德問題變得更加困難，

is not naïve in the slightest.

就像成人學習外語一樣。

It is more akin to a Swiss army knife

但那並非不可能。

with fixed mental modules

最近史丹佛大學有一項很棒的研究

finely honed during development

指出那些曾參與 虛擬實境遊戲的玩家，

and a sharp sense of fairness.

選擇扮演善良、熱心英雄的人

The early years are crucial.

確實在之後會變得

There seems to be a window of opportunity,

比較樂於照顧與幫助他人。

after which mastering moral questions

我的意思並不是

becomes more difficult,

要賦予罪犯超能力，

like adults learning a foreign language.

而是提議我們應該找出一些方法

That's not to say it's impossible.

讓喬和像他這樣的人

A recent, wonderful study from Stanford University

能夠改變他們的大腦和行為，

showed that people who have played

這將有利於他們，

a virtual reality game in which they took on

也有利於我們所有的人。

the role of a good and helpful superhero

那麼大腦能改變嗎？

actually became more caring and helpful

超過一百年來，

towards others afterwards.

神經解剖學家和後來的神經科學家

Now I'm not suggesting

都一致認為在過了 童年初期發展階段之後，

we endow criminals with superpowers,

成人腦無法生長出新的腦細胞。

but I am suggesting that we need to find ways

腦只能在特定條件中才能改變。

to get Joe and people like him

這是在過去所被深信的。

to change their brains and their behavior,

但是到了 1990 年代，

for their benefit

開始有研究顯示，

and for the benefit of the rest of us.

從普林斯頓的 伊莉莎白．古爾德等人開始，

So can brains change?

研究開始顯示神經生成的證據，

For over 100 years,

新的腦細胞生成

neuroanatomists and later neuroscientists

會出現在成年哺乳動物的腦中，

held the view that after initial development in childhood,

一開始會在嗅球，

no new brain cells could grow

主責我們嗅覺的部位；

in the adult human brain.

接下來是在海馬迴，

The brain could only change

這是和短期記憶有關的地方，

within certain set limits.

最後是在杏仁核。

That was the dogma.

為了理解整個流程如何運作，

But then, in the 1990s,

我離開精神病患的研究， 加入哈佛的研究室，

studies starting showing,

專攻學習與發展。

following the lead of Elizabeth Gould at Princeton and others,

我研究老鼠，而非精神病患，

studies started showing the evidence of neurogenesis,

因為同樣的腦反應

the birth of new brain cells

顯現在許多不同的社會型動物上。

in the adult mammalian brain,

因此如果你將一隻老鼠 養在普通的籠子裡，

first in the olfactory bulb,

基本上就是鞋盒，並放入棉花球，

which is responsible for our sense of smell,

單獨飼養，沒有太多刺激，

then in the hippocampus

牠不僅會了無生氣，

involving short-term memory,

而且還常會發展出奇怪、重複的行為。

and finally in the amygdala itself.

這種天生好交際的動物

In order to understand

會失去和其他老鼠連結的能力，

how this process works,

甚至在接觸其他老鼠時， 會變得有攻擊性。

I left the psychopaths and joined a lab in Oxford

然而，把老鼠養在所謂的

specializing in learning and development.

豐富環境之中，

Instead of psychopaths, I studied mice,

和其他老鼠住在較大的地方，

because the same pattern of brain responses

附有輪子、階梯和探索區域，

appears across many different species of social animals.

顯示了神經生成，

So if you rear a mouse in a standard cage,

即新的腦細胞生長，

a shoebox, essentially, with cotton wool,

如我們所見，牠們也會有較佳的表現

alone and without much stimulation,

在學習與記憶的任務上。

not only does it not thrive,

牠們不會建立道德觀，

but it will often develop strange,

不會幫"老"老鼠提購物袋過馬路，

repetitive behaviors.

但是改良的環境會帶來

This naturally sociable animal

健康與友善的行為。

will lose its ability to bond with other mice,

兩相比較，養在普通籠子裡的老鼠，

even becoming aggressive when introduced to them.

你可能會說，和在牢房裡也差不多，

However, mice reared in what we called

已大幅降低腦中新神經元的數量。

an enriched environment,

現在我們已清楚知道 哺乳動物的杏仁核，

a large habitation with other mice

包含像我們的靈長類動物，

with wheels and ladders and areas to explore,

也能顯示神經生成。

demonstrate neurogenesis,

在腦部的某些區塊中，

the birth of new brain cells,

超過 20% 的細胞都是在近期形成。

and as we showed, they also perform better

我們才剛開始理解

on a range of learning and memory tasks.

這些細胞真正的功能是什麼，

Now, they don't develop morality to the point of

但是它意謂著腦也能夠

carrying the shopping bags of little old mice

大幅改變，一直到成年時期。

across the street,

然而，我們的腦也對

but their improved environment results in healthy,

環境中的壓力非常敏感。

sociable behavior.

壓力激素和糖皮質素

Mice reared in a standard cage, by contrast,

都由腦部釋出，

not dissimilar, you might say, from a prison cell,

抑制這些新細胞的成長。

have dramatically lower levels of new neurons

壓力越大，腦部的發展就會越少，

in the brain.

因而導致適應力較差，

It is now clear that the amygdala of mammals,

並且讓壓力更大。

including primates like us,

這是先天與後天之間的相互影響，

can show neurogenesis.

千真萬確發生在我們眼前。

In some areas of the brain,

當你思考這件事時，

more than 20 percent of cells are newly formed.

諷刺的是，我們目前提供

We're just beginning to understand

給有壓力杏仁核人們的解方，

what exact function these cells have,

就是把他們放在

but what it implies is that the brain is capable

其實會抑制任何發育機會的環境。

of extraordinary change way into adulthood.

當然，監禁是必要的處置，

However, our brains are also

對刑事司法系統

exquisitely sensitive to stress in our environment.

以及保護社會的立場都是如此。

Stress hormones, glucocorticoids,

我們的研究並不是說

released by the brain,

罪犯應該將核磁共振攝影

suppress the growth of these new cells.

當做法庭上的證據，

The more stress, the less brain development,

讓罪犯因為有缺陷的杏仁核而免於受罰。

which in turn causes less adaptability

證據其實與此背道而馳。

and causes higher stress levels.

因為我們的腦有改變的能力，

This is the interplay between nature and nurture

我們需要對自己的行為負責，

in real time in front of our eyes.

他們需要負起

When you think about it,

改過遷善的責任。

it is ironic that our current solution

有一種矯正的方式可能有效，

for people with stressed amygdalae

那就是透過修復式司法計畫。

is to place them in an environment

選擇參與計畫的被害者

that actually inhibits any chance of further growth.

會和罪犯面對面，

Of course, imprisonment is a necessary part

在安全的環境下，安排好的會面場景，

of the criminal justice system

罪犯會被鼓勵

and of protecting society.

為自己的行為負責，

Our research does not suggest

被害者在過程中擔任積極的角色。

that criminals should submit their MRI scans

在這種安排中，罪犯可以觀察，

as evidence in court

也許是第一次，

and get off the hook because they've got a faulty amygdala.

被害者以真實人物現身，

The evidence is actually the other way.

有思想、感覺

Because our brains are capable of change,

和真誠的情感反應。

we need to take responsibility for our actions,

這種方式會刺激杏仁核，

and they need to take responsibility

也許會成為一種更有效的矯正練習，