Why is yawning contagious? - Claudia Aguirre

譯者: Anthea Chen 審譯者: Ya Hui Hung

Oh, excuse me!

不好意思！

Have you ever yawned because somebody else yawned?

別人打哈欠

你會不會也打哈欠？

You aren't especially tired,

其實沒有特別累

yet suddenly your mouth opens wide

但突然就張大嘴巴

and a big yawn

一個大哈欠

comes out.

就跑出來了

這現象叫哈欠傳染

This phenomenon is known as contagious yawning.

And while scientists still don't fully understand

對於背後的原因

why it happens,

科學家還不完全了解

there are many hypotheses currently being researched.

但已經有人在研究各種假說

Let's take a look at a few of the most prevalent ones,

讓我們來了解

一些廣為流傳的說法

beginning with two physiological hypotheses

先聽聽 2 種生理假說

before moving to a psychological one.

再看看 1 種心理假說

第 1 種生理假說認為

Our first physiological hypothesis

states that contagious yawning is triggered by a specific stimulus,

哈欠傳染其來有自

會由特定刺激引起

an initial yawn.

就是最初的哈欠

This is called fixed action pattern.

這叫固定行為模式

有點像反射動作

Think of fixed action pattern like a reflex.

Your yawn makes me yawn.

你的哈欠讓我打哈欠

Similar to a domino effect, one person's yawn triggers a yawn

類似多米諾骨牌效應

一個人的哈欠

in a person nearby that has observed the act.

讓附近看到的人也打哈欠

Once this reflex is triggered, it must run its course.

這效應一旦啟動

就會持續一定的時間

Have you ever tried to stop a yawn once it has begun?

快打哈欠時

你有試過阻止自己嗎？

Basically impossible!

根本不可能！

Another physiological hypothesis

第 2 種生理假說

is known as non-conscious mimicry,

叫無意識模仿

or the chameleon effect.

又稱變色龍效應

This occurs when you imitate someone's behavior

人會模仿他人的行為

without knowing it,

下意識地

a subtle and unintentional copycat maneuver.

做出細微、自然的複製動作

人會模仿他人的姿勢

People tend to mimic each other's postures.

If you are seated across from someone that has their legs crossed,

像是對面的人翹腳

你看到了

you might cross your own legs.

很有可能也會翹起腳來

這假說認為

This hypothesis suggests

that we yawn when we see someone else yawn

看到別人打哈欠就跟進

because we are unconsciously copying his or her behavior.

是因為不知不覺中

我們會模仿他人的行為

科學家相信

Scientists believe that this chameleon effect is possible

變色龍效應可能和特殊的神經元有關

because of a special set of neurons known as mirror neurons.

也就是鏡像神經元

Mirror neurons are a type of brain cell

鏡像神經元是一群腦細胞

that responds equally when we perform an action

像鏡子一樣

as when we see someone else perform the same action.

看到他人的動作後

我們會做出相同的動作

These neurons are important for learning and self-awareness.

這組神經元很重要

尤其對學習和自我覺察

For example, watching someone do something physical,

例如，看到別人的動作

like knitting or putting on lipstick,

像是編織

或是擦口紅

can help you do those same actions more accurately.

能讓我們精確地做出相同的動作

Neuroimaging studies using fMRI, functional magnetic resonance imaging,

腦神經影像利用醫學技術

也就是功能性核磁共振造影

show us that when we seem someone yawn or even hear their yawn,

發現看到別人打哈欠

或只是聽到哈欠聲

a specific area of the brain housing these mirror neurons

我們腦中

有鏡像神經元的區塊

tends to light up,

會有反應

which, in turn, causes us to respond with the same action:

促使我們做出回應

重複相同的動作：打哈欠

a yawn!

最後要談的心理假說

Our psychological hypothesis also involves the work of these mirror neurons.

也和鏡像神經元有關

We will call it the empathy yawn.

稱為同理哈欠

同理心是種能力

Empathy is the ability to understand what someone else is feeling

能感知他人的感受

and partake in their emotion,

融入對方的情緒

a crucial ability for social animals like us.

對人這種社會性動物很重要

近來，神經學家發現

Recently, neuroscientists have found that a subset of mirror neurons

鏡像神經元有組子集

allows us to empathize with others' feelings

能讓我們同理他人

at a deeper level.

而且是深層同理

(Yawn)

Scientists discovered this empathetic response to yawning

事實上

同理哈欠現象

while testing the first hypothesis we mentioned,

是在測試固定行為時

fixed action pattern.

所發現的

這研究假設

This study was set up to show that dogs would enact a yawn reflex

如果狗聽到人類打哈欠

at the mere sound of a human yawn.

也會反射性地打起哈欠

不僅證實了這種現象

While their study showed this to be true, they found something else interesting.

還發現了其他有趣的事

Dogs yawned more frequently at familiar yawns,

熟人的哈欠對狗比較有影響力

such as from their owners,

像是主人

than at unfamiliar yawns from strangers.

但對陌生人就不是了

Following this research, other studies on humans and primates

同樣地

以人類和靈長類為研究對象

have also shown that contagious yawning

也證實哈欠傳染

occurs more frequently among friends than strangers.

在熟人間發生的機率高於陌生人

事實上，早在4、5 歲時

In fact, contagious yawning starts occurring

when we are about four or five years old,

對哈欠傳染就有反應了

at the point when children

那時

develop the ability to identify others' emotions properly.

兒童開始能正確了解他人的情緒

Still, while newer scientific studies aim to prove that contagious yawning

儘管相關研究推陳出新

想證明哈欠傳染的產生

is based on this capacity for empathy,

是因為同理能力

more research is needed to shed light on what exactly is going on.

但其實

更需要研究的是背後的機制

說不定真正的答案

It's possible that the answer lies in another hypothesis altogether.

就藏在其他假說裡

下次打哈欠時

The next time you get caught in a yawn,

take a second to think about what just happened.

停下來想想剛才的情形

Were you thinking about a yawn?

是不是想到了哈欠這件事？

Did someone near you yawn?

附近有人打哈欠嗎？

Was that person a stranger or someone close?

是熟人？還是陌生人？

And are you yawning right now?

你現在在打哈欠嗎？

(Yawn)

(Lip smacking)