Why is yawning contagious Claudia Aguirre

Oh, excuse me!

Have you ever yawned
because somebody else yawned?

You aren’t especially tired,

yet suddenly your mouth opens wide

and a big yawn

comes out.

This phenomenon is known
as contagious yawning.

And while scientists still
don’t fully understand

why it happens,

there are many hypotheses
currently being researched.

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

beginning with two
physiological hypotheses

before moving to a psychological one.

Our first physiological hypothesis

states that contagious yawning
is triggered by a specific stimulus,

an initial yawn.

This is called fixed action pattern.

Think of fixed action pattern
like a reflex.

Your yawn makes me yawn.

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

in a person nearby
that has observed the act.

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

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

Basically impossible!

Another physiological hypothesis

is known as non-conscious mimicry,

or the chameleon effect.

This occurs when you
imitate someone’s behavior

without knowing it,

a subtle and unintentional
copycat maneuver.

People tend to mimic
each other’s postures.

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

you might cross your own legs.

This hypothesis suggests

that we yawn when we see someone else yawn

because we are unconsciously copying
his or her behavior.

Scientists believe that this chameleon
effect is possible

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

Mirror neurons are a type of brain cell

that responds equally
when we perform an action

as when we see someone else
perform the same action.

These neurons are important
for learning and self-awareness.

For example, watching someone
do something physical,

like knitting or putting on lipstick,

can help you do those same
actions more accurately.

Neuroimaging studies using fMRI,
functional magnetic resonance imaging,

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

a specific area of the brain
housing these mirror neurons

tends to light up,

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

a yawn!

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

We will call it the empathy yawn.

Empathy is the ability to understand
what someone else is feeling

and partake in their emotion,

a crucial ability
for social animals like us.

Recently, neuroscientists have found
that a subset of mirror neurons

allows us to empathize
with others' feelings

at a deeper level.

(Yawn)

Scientists discovered
this empathetic response to yawning

while testing the first
hypothesis we mentioned,

fixed action pattern.

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

at the mere sound of a human yawn.

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

Dogs yawned more frequently
at familiar yawns,

such as from their owners,

than at unfamiliar yawns from strangers.

Following this research,
other studies on humans and primates

have also shown that contagious yawning

occurs more frequently
among friends than strangers.

In fact, contagious
yawning starts occurring

when we are about four or five years old,

at the point when children

develop the ability to identify
others' emotions properly.

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

is based on this capacity for empathy,

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

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

The next time you get caught in a yawn,

take a second to think
about what just happened.

Were you thinking about a yawn?

Did someone near you yawn?

Was that person a stranger
or someone close?

And are you yawning right now?

(Yawn)

(Lip smacking)

哦,对不起!

你有没有
因为别人打哈欠而打哈欠?

你并不特别累,

但突然嘴巴张

得大大的,打了一个大大的

哈欠。

这种现象被
称为传染性打哈欠。

虽然科学家们仍然
不完全理解

为什么会发生这种情况,

但目前有许多假设
正在研究中。

让我们看
一些最流行的假设,

从两个生理假设开始,

然后再转向心理假设。

我们的第一个生理假设

指出,传染性打哈欠
是由特定刺激引发的,

即最初的打哈欠。

这称为固定动作模式。

把固定的动作模式想象
成一种反射。

你打哈欠让我打哈欠。

类似于多米诺骨牌效应,
一个人的哈欠会触发

附近观察该行为的人打哈欠。

一旦触发了这种反射,
它就必须顺其自然。

你有没有试过在
打哈欠开始时阻止它?

基本不可能!

另一种生理学假设

被称为无意识模仿,

或变色龙效应。

当您在不知情的情况下模仿某人的行为时,就会发生这种情况,这是

一种微妙且无意的
模仿动作。

人们倾向于模仿
彼此的姿势。

如果您坐在
双腿交叉的人对面,

您可能会交叉自己的双腿。

这个假设

表明,当我们看到别人打哈欠时

,我们也会打哈欠,因为我们无意识地模仿
了他或她的行为。

科学家认为,这种变色龙
效应是可能的,

因为有一组特殊的神经元
被称为镜像神经元。

镜像神经元是一种脑细胞


当我们执行某个

动作时,它的反应与我们看到其他人
执行相同动作时的反应相同。

这些神经元
对于学习和自我意识很重要。

例如,看某人
做一些身体上的事情,

比如编织或涂口红,

可以帮助你
更准确地做同样的动作。

使用 fMRI(
功能性磁共振成像)进行的神经影像学研究

表明,当我们看起来有人打哈欠
甚至听到他们打哈欠时,

容纳这些镜像神经元的大脑特定区域

往往会亮起,

这反过来又会导致我们
以 同样的动作

:打哈欠!

我们的心理假设也涉及
这些镜像神经元的工作。

我们将其称为移情哈欠。

同理心是
理解他人感受

并参与他们情绪

的能力,
对于像我们这样的社会动物来说,这是一项至关重要的能力。

最近,神经科学家发现
,镜像神经元的一个子集

可以让我们更深层次
地理解他人的

感受。

(打哈欠)

科学家们

在测试我们提到的第一个
假设,即

固定动作模式时,发现了这种对打哈欠的移情反应。

这项研究旨在表明
,狗

只要听到人类打哈欠的声音就会产生打哈欠反射。

虽然他们的研究表明这是真的,
但他们发现了其他有趣的东西。


在熟悉的打哈欠下打哈欠的频率更高,

比如主人打哈欠,而

不是陌生人打不熟悉的打哈欠。

在这项研究之后,
其他关于人类和灵长类动物的

研究也表明,传染性打哈欠

在朋友之间比陌生人更频繁地发生。

事实上,传染性
打哈欠

在我们大约四五岁时开始发生,

此时孩子们

已经具备正确识别
他人情绪的能力。

尽管如此,虽然较新的科学研究
旨在证明传染性打哈欠

是基于这种同理心的能力,但仍

需要更多的研究来
阐明究竟发生了什么。

答案可能
完全在于另一个假设。

下次你打哈欠时,

花点时间
想想刚刚发生的事情。

你在想打哈欠吗?

你附近有人打哈欠吗?

那个人是陌生人
还是亲近的人?

你现在在打哈欠吗?

(打哈欠)

(咂嘴)