The Science Behind How Sickness Shapes Your Mood | Keely Muscatell | TED

翻译人员: Li Jiaying 校对人员: Yip Yan Yeung

Alright, I'd like you to take a moment.

好的，我想让大家花点时间，

Think about a time when you were recently sick.

想想你最近一次生病的时候。

Try specifically to think of a time when,

试着想一想具体哪一次，

even though you weren't feeling all that great,

尽管你觉得不是特别舒服，

you still felt well enough to get up out of bed,

但你仍然感觉还行 至少还能起床，

go about your day.

开始新的一天。

OK, what was your mood like?

好吧，你的心情怎么样？

Did you feel a little sad or depressed?

你感到有点悲伤或沮丧吗？

What types of social interactions did you want to have?

你想进行什么类型的社交互动？

Would you have wanted to go to a cocktail party full of strangers

你想参加一个 全是陌生人的鸡尾酒会

or out on a first date?

还是出门进行第一次约会？

I'm a psychology professor

我是一名心理学教授

at the University of North Carolina at Chapel Hill,

来自北卡罗来纳大学 教堂山分校。

and for the past 15 years,

在过去的 15 年中，

I've been studying the interconnections between physiological changes

我一直在研究生病期间 身体发生的生理变化

happening in the body during sickness

与心理和社会健康

and psychological and social well-being.

之间的相互关系。

Specifically my lab studies social psychoneuroimmunology,

具体而言，我的实验室研究的是 社交心理神经免疫学，

which is a mouthful to say,

这个词说起来有点拗口，

and is a field of research that's dedicated

这是一片致力于

to discovering interactions between our social experiences,

发现我们社会经历、心理过程

psychological processes and the immune system.

和免疫系统之间相互作用的研究领域。

Today, I want to tell you about some research showing

今天，我想告诉你一些研究表明

that the same physiological changes happening in your body

在你体内发生的同样的生理变化

that cause the physical symptoms you have when you're sick,

导致生病时产生的身体症状

are also shaping your mood and your social behavior.

也在影响你的情绪和社交行为。

In other words, changes in the immune system

换句话说，免疫系统的变化

can signal to the brain to cause us to think,

可以向大脑发出信号， 让我们用不同的方式

feel and act differently.

去思考、感知和行动。

And not only that, but also our social experiences can cause changes

不仅如此，我们的社交经历也会导致

in our immune systems.

我们的免疫系统发生变化。

So purely psychological things happening in our brains

因此，我们大脑中 发生的纯粹心理变化

can cause the immune system to ramp up or ramp down.

可能会导致免疫系统 增强或减弱。

Because of that, we can get caught in these vicious cycles

正因为如此，我们可能 会陷入恶性循环，

where our psychological experiences can cause changes in our immune system,

在这过程中，我们的心理经历 会导致我们的免疫系统发生变化，

and those immunological shifts can cause changes

而这些免疫的改变可能 让我们的内心体验

to our psychological experiences.

发生变化。

Now the component of the immune system

现在，大多数心理神经免疫学研究

that most research in psycho- neuroimmunology focuses on

关注的免疫系统组成部分

is the inflammatory response or inflammation.

是炎症反应或炎症。

The inflammatory response is your immune system's

炎症反应是免疫系统

first line of defense against injury or infection,

抵御受伤或感染的第一道防线，

and it's coordinated by these molecules

它是由这些被称为

that are called pro-inflammatory cytokines.

促炎细胞因子的分子来协调的。

You can think of cytokines as sort of the chemical messengers

你可以将细胞因子视为

of the immune system.

免疫系统的化学信使。

So they're out there right now, swimming through your bloodstream.

它们现在就在那， 在你的血液中游动。

And if an immune cell finds something weird or out of the ordinary,

如果免疫细胞发现 一些奇怪或不寻常的东西，

they'll tell those cytokines to signal to other immune cells

它们会告诉这些细胞因子 向其他免疫细胞发出信号

to come and check it out.

让它们过来检查一下。

So if you think about a time you've had a paper cut,

所以如果你回想一下 被纸割伤的经历，

you may have noticed that the area around the cut swells,

你可能会注意到 切口周围的区域会肿胀，

it turns red, it heats up.

变红，发热。

That's the inflammatory response in action.

这就是炎症反应在发挥作用。

And those symptoms are caused by your cytokines doing their job,

而这些症状是由于 你的细胞因子正发挥作用，

sending out signals to other immune cells to come and heal the cut.

向其他免疫细胞发出信号， 让它们来愈合伤口。

The same thing happens if your immune cells find a virus

如果你的免疫细胞 在体内发现病毒或细菌

or a bacteria in the body.

也会发生同样的情况。

They send out cytokines to signal to other immune cells

它们发出细胞因子 向其他免疫细胞发出信号

to come and try and eliminate the pathogen.

让它们前来尝试消灭病原体。

Now in doing this, cytokines cause

这样做，细胞因子会导致

the physical symptoms we commonly have when we're sick.

我们生病时通常出现的身体症状。

Things like fever and achiness and fatigue.

诸如发烧、疼痛和疲劳之类。

So even though we usually think of those symptoms as being caused by a virus

因此，尽管我们通常认为 这些症状是由某种病毒

or a bacteria itself,

或细菌本身引起的

they're actually caused by our own immune systems

但它们实际上是由于 我们自己的免疫系统

activating to try to eliminate the pathogen.

被激活以试图消灭病原体导致的。

But in addition to those physical symptoms,

但除了这些身体症状外，

decades of research,

数十年来

in both animals and humans,

对动物和人类的研究

clearly shows that cytokines also cause changes to our mood

清楚地表明，细胞因子也会引起我们情绪

and to our social behavior.

和社交行为的变化。

So inflammation in the body can signal to the brain

因此，体内的炎症 可以向大脑发出信号

to cause us to feel down,

使我们感到心情低落、

depressed and even hopeless.

郁闷甚至绝望。

Inflammation can also make us want to socially withdraw from other people

炎症还可能使我们 想在社交上远离他人

to avoid interacting with individuals in our social networks.

以避免和我们社交网中的人互动。

So this research shows the powerful influence that the immune system can have

因此这项研究表明，免疫系统 可以对我们的情绪和社交行为

on our mood and on our social behavior.

产生强大的影响。

Changes in inflammation in the body

体内的炎症变化

can signal to the brain to cause us to feel depressed and even lonely.

可以向大脑发出信号 使我们感到忧郁甚至孤独。

OK, so you may be wondering,

好的，所以你可能想知道

why on Earth would your body do this?

到底为什么你的身体会这样？

Why would you want your immune system to be able to manipulate your brain

为什么你让你的免疫系统 能够去操纵你的大脑

and cause you to feel sad and distant from other people in your life?

让你感到悲伤并想要 疏远生活中的其他人？

While we can't know for sure why this happens,

虽然我们无法确定 为什么会发生这种情况，

evolutionary theory provides some good food for thought.

进化论提供了 一些很好的思考依据。

The fact is,

事实是，

revving up and running the immune system takes a lot of energy.

加速和运行免疫系统 需要大量能量。

Getting cytokines to swim through the bloodstream

让细胞因子在血液中游动

and send signals to immune cells takes calories.

并向免疫细胞发送信号 会消耗卡路里。

And what else takes calories?

还有什么需要卡路里呢？

Pretty much everything.

几乎所有东西。

Especially things like going out and seeking pleasurable experiences,

尤其是诸如外出和寻找愉快体验、

interacting with strangers

与陌生人互动

and just generally moving about the world.

或只是寻常地探索世界之类的。

So the theory is that the immune system is telling the brain to feel depressed

因此理论是，免疫系统 会告诉大脑感到沮丧

and to withdraw from socializing

并退出社交活动，

because it wants you to stay at home and rest.

因为它希望你待在家里休息。

And if things that would normally sound fun

而且如果平常听起来很有趣的事

just don't seem all that fun,

看起来不那么有趣了，

and if interacting with other people seems exhausting

如果他人互动看起来很累

and maybe even a little threatening,

甚至可能有点危险，

then we'll be less likely to do those things

那我们做这些事的可能性就会降低

and more likely to stay at home

而更有可能待在家里

and let our immune systems use our calories.

让免疫系统使用我们的卡路里。

Now, of course, if this becomes prolonged and inflammation is elevated over weeks

当然如果这种情况持续很久， 炎症在数周内加剧

or even years,

甚至数年内不断加重，

that could have really terrible impacts on our well-being.

那可能会对我们的健康 产生非常严重的影响。

But in the short term,

但在短期内，

we think of this immune-to-brain signaling as adaptive.

我们认为这种脑免疫信号 是自适应的。

Your immune system is basically good at knowing when it would be a good idea

基本上你的免疫系统很擅于决定 对你来说什么时候外出

for you to be out interacting with the world and the people in it,

与世界和世上的人互动 是个好主意，

and when it would be better to just stay at home.

以及什么时候 待在家里会更好。

But it turns out, the influence of inflammation on our social lives

但事实证明， 炎症对我们社交生活的影响

isn't as simple as always making us feel more disconnected

并不只是使我们感到更疏远

and socially withdrawn.

和更社交孤僻那样简单。

One of the most important discoveries

我们最近在这一研究领域

that we've made in this area of research recently

取得的最重要的发现之一

is that inflammation might actually make us more motivated

是炎症实际上可能使我们更有动力

to seek some social interactions,

去寻求某些社交互动，

specifically those with the people who we're closest to.

特别是与最亲近人的往来

So it’s not that inflammation makes us less social across the board,

因此，并不是说炎症 会让我们全面减少社交，

it may just make us more selective about who we want to socialize with.

它可能只会让我们选择 对自己想交往的人时更挑剔。

To discover this, my colleagues and I ran an experiment.

为了发现这一点， 我和同事们做了一项实验。

We asked participants in our study

我们要求研究的参与者

to send us digital photographs of someone who they could go to

向我们发送某些人的数码照片， 如果他们在需要帮助或支持时

if they needed help or support.

会去找的这些人。

As you would expect, people sent us photos of their romantic partners,

如您所料，人们给我们发送了 他们的浪漫关系的伴侣、

their closest friends and their family.

他们最亲密的 朋友和家人的照片。

Then we had our participants view those images of their support figure

然后，我们让参与者看着 他们精神支柱者的照片，

while we tracked their brain activity using MRI scanning.

同时我们用核磁共振成像扫描 来追踪他们的大脑活动。

Now, critically, prior to the MRI scans,

现在重要的是， 在核磁共振成像扫描前，

we exposed a random half of the participants in our study

我们随机让一半的研究参与者暴露在

to a bacteria which cause levels of inflammation in the body to increase.

一种会导致体内炎症水平升高的细菌下。

The other half just had normal, low levels of inflammation.

而另一半的炎症水平则正常且较低。

And what we found is that for the people who we exposed to that bacteria,

我们发现，对于接触过这种细菌

who had lots of cytokines in their body,

导致体内有大量细胞因子的人来说，

they actually showed more activity in a reward-related region of the brain,

他们实际上在大脑内 一块与奖励相关的区域会更活跃，

called the ventral striatum,

即腹侧纹状体，

when they viewed images of their support figures

当他们看到自己精神支柱的照片时

relative to the people who had low levels of inflammation.

相较于那些炎症水平低的人 此区域会表现出更多的活性。

So what this suggests

因此，这表明

is that while inflammation might make social interactions with strangers

尽管炎症可能会使 与陌生人的社交互动

seem less rewarding,

显得不那么有益，

it doesn't necessarily make all social interactions seem less rewarding.

但它并不一定会使 所有社交互动的回报降低。

In fact, inflammation may make us more motivated to seek interactions

实际上，炎症可能使我们 更有动力去寻求

with people who could provide us with comfort or care.

和能为我们提供 安慰或护理的人进行互动。

Those who could be a shortcut to chicken soup.

那些会给我们 提供便利或炖鸡汤的人。

But of course, it's not every day

但当然，并不是每天

that we come into contact with a virus or a bacteria,

我们都会接触到病毒或细菌，

or that we have a wound

我们也不是每天都有

that causes our levels of inflammation to increase.

导致炎症水平升高的伤口。

So how much of a day-to-day influence on our social lives

那么，免疫系统实际上 对我们的社交生活

does the immune system actually have?

有多少日常影响呢？

Research shows that the answer is a lot more than you might think.

研究表明，答案是 影响要比你想象的要多得多。

That's because one of the most robust findings

那是因为所有心理神经免疫学研究中

in all of psychoneuroimmunology research

最有力的发现之一

is that stress causes inflammation.

是压力会导致炎症。

So purely psychological things happening in the brain

因此，仅是大脑中出现的心理影响

can cause increases in cytokines in the body.

也会导致体内细胞因子的增加。

This is true across species,

这发生在所有物种之间，

from rodents to primates to humans.

从啮齿动物到灵长类再到人类都是如此。

In my lab and in others across the globe,

在我和全球其他地方的实验室，

we study the effects of stress on inflammation

我们为了研究压力对炎症的影响，

by asking people to come into the lab and give a ten-minute,

要求人们进入实验室发表十分钟的

off-the-cuff speech

即兴演讲，

about why they'd be a good candidate for their dream job.

讲述为什么他们 是自己理想工作的好人选。

And then they have to do challenging mental math out loud.

然后他们必须大声地 做出有挑战性的数学口算。

And they do this all in front of a panel of experts who's judging them.

并且他们要在评判他们的 专家组面前完成这一切。

Yeah, people report that this is stressful.

是的，测试者汇报说这很有压力。

And critically,

至关重要的是，

in response to this psychologically stressful experience,

为了应对这种心理压力的经历，

we see that levels of cytokines in the body have increased.

我们发现体内细胞因子的水平有所增加。

Let's take a second and really appreciate that remarkable finding.

让我们花点时间真正欣赏 这一非凡的发现。

In the absence of anything physically wrong with the body --

在身体机能没有任何问题的情况下，

no viruses, no bacteria, no wounds --

没有病毒，没有细菌，没有伤口——

a purely psychological stressor

纯粹的心理压力

is causing the inflammatory response to activate.

会导致炎症反应被激活。

So it's not just that our immune systems are sending signals to our brain,

因此，不仅是我们的免疫系统 向我们的大脑发送信号，

but also our brains are sending signals to our immune systems

我们的大脑也在 向免疫系统发送信号

telling them to activate in response to stress that we encounter.

告诉它们需要激活 以应对我们遇到的压力。

OK, so now that you know

好的，既然你知道了

that your immune system has this very active social life

你的免疫系统 有这样非常活跃的社交生活

and that your brain and your immune system are constantly communicating

并且你的大脑和免疫系统不断地

in ways that could make you feel depressed or lonely,

用一种可能让你感到 沮丧或孤独的方式进行沟通，

what should you do?

你该怎么办？

For me, knowing about the social life of the immune system

对我来说，了解免疫系统的社交生活

has changed my life,

改变了我的生活，

in part because it gives me an explanation

部分原因是它向我解释了

for why I might feel physically crummy at the end of a stressful day,

为什么在紧张的一天结束后 我可能会感到身体不适，

or why I might feel a little down

又或者为什么我可能会感到有些情绪低落

and disconnected from other people when I'm feeling physically unwell.

且不想和他人联系， 当我感到身体不适的时候。

So, for example,

因此，举例来说，

the experience of giving this talk today has been really rewarding

今天发表这个演讲的经历 确实很有收获

and also quite challenging.

也很有挑战性。

You might even say it was, at times, stressful.

你甚至可能会说， 有些时候压力很大。

And I'm sure you've had similar experiences in your lives.

而且我敢肯定，你在生活中 也有过类似的经历。

Maybe it was a difficult task you had to complete at work,

可能是你在工作中 必须完成的艰巨任务，

a confrontation with a spouse or a family member,

与配偶或家庭成员发生冲突，

or just some problem that cropped up in your life

或者只是生活中突然出现的一些问题

that you had to quickly figure out how to solve.

使你必须迅速想办法解决。

Based on what I've told you here today,

根据我今天在这里告诉你的内容，

I hope you're predicting that in response to these stressful experiences,

我希望你能预测到， 为了应对这些紧张的经历，

we're likely to have high levels of inflammation in our bodies.

我们体内可能会出现高水平的炎症。

Our cytokines will have come out in full force

我们的细胞因子将全力发挥作用，

in response to the stress we've experienced.

以应对我们所经历的压力。

And because of that,

因此，

if we then feel exhausted

如果我们随后感到精疲力尽，

and a bit like we've failed

有点像我们没做好，

and we don't want to go anywhere or see anyone or do anything,

我们不想去任何地方， 见任何人，或做任何事，

and we just want to stay at home and relax on the couch

只想待在家里，和最亲近的人

with the people who we're closest to,

一起在沙发上放松一下，

we'll know why.

我们就会知道原因。

And because we know that those symptoms are likely just our immune systems

而且，因为我们知道 这些症状很可能只是我们的免疫系统

telling our brains to feel depressed

正告诉我们的大脑要感到沮丧

and to withdraw from social interactions

并退出社交互动，

so that we stay at home to rest, relax and recuperate,

这样我们就可以待在家里休息、 放松和恢复精力，

we don't have to agonize

我们不必苦恼

over why we're maybe feeling a little down on ourselves,

为什么我们有点沮丧，

or a little distant from other people.

或与他人有些疏远。

We can rest assured that

我们可以放心，

in the coming days,

在接下来的几天里，

we'll be feeling much more like ourselves again

我们会再次感觉自己好起来，

as our cytokine levels go back down.

随着细胞因子水平的降低回归正常。

So in the future,

因此，将来，

when you encounter stress in your life

当你在生活中遇到压力

and you feel those reins of inflammation start to take hold,

并感觉到炎症 如缰绳一般开始控制你时，

I hope you remember what I've told you here today.

我希望你记住 我今天在这里告诉你的话。

And you remind yourself that those symptoms you're experiencing,

然后你提醒自己， 这些你正在经历的症状，

that's likely just your immune system

很可能只是你的免疫系统

doing its job,

正在发挥作用，

telling your brain to feel depressed and withdrawn

告诉你的大脑 感到沮丧和退缩，

as evolution intended,

正如进化的目的，

to keep you healthy in the long term.

以保持你的长期健康。

Thank you very much.

非常感谢。

(Applause)

（掌声）