Why do we cry? The three types of tears - Alex Gendler

人為什麼會哭？三種不同的眼淚 - Alex Gendler

譯者: Annie Huang 審譯者: Yichum Wu

Our story is about a girl named Iris.

這個故事是關於一個女孩艾莉絲

Iris is very sensitive.

艾莉絲非常多愁善感

(Bird cawing)

So much that she is always in tears.

所以總是淚眼汪汪的樣子

She cries when she's sad,

她傷心時哭

開心時也哭

when she's happy,

(Godzilla roars)

甚至有東西靠近就會嚎啕大哭

and even tears up when things just get to her.

She has special lacrimal glands to make new tears

艾莉絲有特殊的淚腺 能夠製造新的眼淚

and special tubes, called lacrimal puncta,

以及特殊的管口，叫作淚點

to drain old ones away.

來排掉舊的眼淚

And she cries so much that she goes through

艾莉絲太愛哭了

ten ounces of tears per day,

淚水多達一天0.3公升

thirty gallons a year!

一年就有114公升

In fact, if you look closely,

其實，如果你看得夠仔細

you'll see that she's crying a little bit all the time.

就會發現她一直或多或少在流淚

The basal tears that Iris constantly produces

艾莉絲不斷產生的基本眼淚

form a thin coating of three layers

形成一個三層的薄膜

that cover her and keep dirt and debris away.

阻擋灰塵跟碎屑進入

Right next to Iris is the mucus layer,

在艾莉絲旁的是黏液層

which keeps the whole thing fastened to her.

黏液層使所有東西繫在艾莉絲上

On top of it is the aqueous layer,

在艾莉絲上面的是水層

which keeps Iris hydrated, repels invasive bacteria,

讓她能夠一直保持在含水的狀態

擊退入侵的細菌

and protects her skin, or cornea, from damage.

保護艾莉絲外層的角膜不被破壞

And, finally, there is the lipid layer,

最後是油脂層

an oily outer film that keeps the surface smooth

外層的含油薄膜，使表面保持平滑

for Iris to see through,

讓艾莉絲看得很透徹

and prevents the other layers from evaporating.

並避免其他層失去水分

一般來說，艾莉絲在一天當中

Normally, Iris goes about her day

without really noticing the basal tears doing their thing.

並不太會發現基本眼淚在發揮功能

That's kind of their whole point.

而這也可以算是它們的特性

But one day, she meets a girl named Onion.

有一天艾莉絲遇到了 另一名叫作洋蔥的女孩

Iris is immediately smitten.

艾莉絲要遭殃了

Onion looks gorgeous in her bright purple jacket,

身穿亮紫色夾克的 洋蔥看起來棒透了

and she smells terrific.

聞起來也很完美

So, Iris invites Onion to her house for dinner.

因此艾莉絲邀請 洋蔥到她家吃晚餐

但當洋蔥進門脫下紫色夾克時

But when she comes in and takes off her jacket,

something terrible happens.

悲劇發生了

You see, when Onion's jacket is removed,

你瞧，當洋蔥脫下衣服時

a chemical reaction happens,

化學反應發生了

converting the sulfoxides that make her smell so great

原本讓她聞起來如此美妙的亞碸

into sulfenic acid,

轉換成次磺酸

which then becomes a nasty substance with a long name:

接著變成名字很長的討厭東西

syn-Propanethial S-oxide.

丙硫醛-S-氧化物

The gas stings Iris, and suddenly, she can't help it,

散發的氣體讓艾莉絲感到難受

突然間，她受不了了

she starts weeping uncontrollably.

艾莉絲無法自拔的開始哭泣

These reflex tears are different from the basal tears

這些反射眼淚不同於 艾莉絲熟悉的基本眼淚

that Iris is used to.

Because they're designed

它們的存在是用來 洗刷有害的物質或微粒

to wash away harmful substances, or particles,

they're released in much larger amounts,

反射眼淚比基本眼淚更大量的釋放

and their aqueous layer contains more antibodies

而且反射眼淚的水層有更多抗體

to stop any microorganisms that may be trying to get in, as well.

同時也阻止可能進入的微生物

Both Iris and Onion are devastated.

艾莉絲和洋蔥都身心俱疲

They know they can't continue their relationship

他們知道彼此不可能成為朋友

如果艾莉絲會受傷流淚

if Iris is going to hurt and cry every time Onion takes off her jacket.

只要洋蔥脫掉上衣

So, they decide to break up.

所以她們決定分道揚鑣

As Onion walks out the door, Iris stops crying.

當洋蔥走出門口時

艾莉絲突然間不哭了

And immediately starts again.

可是馬上又開始哭

Only now, she's not crying reflex tears but emotional tears.

此時此刻，艾莉絲流的 不是反射眼淚

而是因傷心流的淚

When someone is either too sad or too happy,

當一個人太傷心或太開心時

it feels like a loss of control,

就會像失去控制一樣

which can be dangerous.

這是很危險的

So, emotional tears are sent in to stabilize the mood

所以情感眼淚就是用來

儘可能趕快使情緒穩定

as quickly as possible,

along with other physical reactions,

同時伴隨其他的生理反應

such as an increased heart rate and slower breathing.

像是漸增的心跳次數

以及變緩的呼吸

But scientists still aren't sure

但科學家始終沒有把握

exactly how or why the tears themselves are helpful.

究竟這些情感眼淚怎麼帶來益處

They may be a social mechanism to elicit sympathy or show submission.

情感眼淚可能是一種社交機制

來引起同情或表示順從

But some studies have also found

但一些研究同時也發現

that emotional tears contain higher levels of stress hormones,

情感眼淚包含更高程度的

壓力賀爾蒙

such as ACTH and enkephalin,

像是促腎上腺皮質激素和腦素

an endorphin and natural pain killer.

一種腦內啡及天然的止痛劑

In this case, emotional tears are also directly calming Iris down,

如此，情感眼淚能夠 直接舒緩艾莉絲的情緒

as well as signaling her emotional state to others.

同時讓別人知道她的心理狀態

Sorry things didn't work out with Onion, Iris,

艾莉絲抱歉囉，洋蔥她不適合你

but don't worry.

但也別擔心

As long as you have all three kinds of tears

只要你擁有這三種眼淚

working to keep you balanced and healthy, it will get better.

並努力讓自己保持平衡且健康

情況一定會越來越好的

You'll see.

你等著瞧吧