The left brain vs. right brain myth - Elizabeth Waters

譯者: Szu-Wen Kung 審譯者: Cissy Yun

Behold the human brain,

仔細觀察人腦

it's lumpy landscape visibly split into a left and right side.

皺褶滿布的腦部 顯而易見分為左右兩邊

This structure has inspired one of the most pervasive ideas about the brain,

此結構形成人們 對腦部最普遍的觀點

that the left side controls logic

左腦控制邏輯

and the right, creativity.

右腦掌控創造力

And yet, this is a myth unsupported by scientific evidence.

不過這個迷思並無科學根據

So how did this misleading idea come about,

所以未經證實的看法從何而來

and what does it get wrong?

而其中又有什麼誤點呢？

It's true that the brain has a right and a left side.

人腦的確有左右之分

This is most apparent with the outer layer, or the cortex.

很明顯能從腦皮層看出

Internal regions, like the striatum,

腦的內部區塊，如紋狀體

hypothalamus,

下視丘

thalamus,

視丘

and brain stem

和腦幹

appear to be made from continuous tissue,

都是由連續的組織所構成

but in fact, they're also organized with left and right sides.

但這些區塊也分為左右兩邊

The left and the right sides of the brain do control different body functions,

左右腦確實掌控不同的身體功能

such as movement and sight.

像是動作和視覺

The brain's right side controls the motion of the left arm and leg and vice versa.

右腦控制左手臂和左腿的動作 左腦則控制另一邊

The visual system is even more complex.

視覺系統更是複雜

Each eye has a left and right visual field.

眼睛各有一個左右視野

Both left visual fields are sent to the right side of the brain,

左視野得到的訊息傳送至右腦

and both right fields are sent to the left side.

右視野的訊息則傳至左腦

So the brain uses both sides to make a complete image of the world.

因此腦運用左右兩側 勾勒完整的影像

Scientists don't know for sure why we have that crossing over.

科學家不確定為何 會有左右交互作用

One theory is it began soon after animals developed more complex nervous systems

有一說是動物神經系統 發展愈趨精密後

開始有這種左右交互模式

because it gave the survival advantage of quicker reflexes.

動物因此反應更快 而具備生存優勢

If an animal sees a predator coming from its left side,

若動物看到掠食者自左方而來

it's best off escaping to the right.

從右邊逃脫最有利

So we can say that vision and movement control are two systems

所以視覺和動作的控制是兩個系統

that rely on this left-right structure,

仰賴左右交互作用的結構

but problems arise when we over-extend that idea to logic and creativity.

但一旦我們將此概念延伸至 邏輯和創造力，就會產生問題

This misconception began in the mid-1800s

此誤解始於十九世紀中葉

when two neurologists, Broca and Wernicke,

源自於兩名神經學家 布洛卡與維尼齊

examined patients who had problems communicating due to injuries.

檢查因傷而造成溝通障礙的病人

The researchers found damage to the patients' left temporal lobes,

他們發現病人的左顳葉有損傷

so they suggested that language is controlled by the left side of the brain.

因此認為語言是由左腦所控制

That captured the popular imagination.

此說法引發 大受歡迎的左右腦之說

Author Robert Louis Stevenson

蘇格蘭作家 羅伯特·路易斯·史蒂文森

then introduced the idea of a logical left hemisphere

提出邏輯左腦與情緒右腦

competing with an emotional right hemisphere

兩邊相互較量的觀點

represented by his characters Dr. Jekyll and Mr. Hyde.

由他的故事人物 傑克博士和海德先生引喻代表

But this idea didn't hold up when doctors and scientists

然而此觀點並站不住腳 尤其是當醫生與科學家

examined patients who were missing a hemisphere

檢查缺少另一半腦部

or had their two hemispheres separated.

或兩邊腦部分離的病人

These patients showed a complete range of behaviors,

這些病人也展現完整的行為

both logical and creative.

邏輯和創造兼具

Later research showed that one side of the brain is more active than the other

稍後的研究顯示在某些功能方面

for some functions.

腦部的一邊會比另一邊更活躍

Language is more localized to the left

語言功能與左腦較為緊密

and attention to the right.

注意力則是與右腦

So one side of the brain may do more work,

因此腦的一邊可能更活躍

but this varies by system rather than by person.

但這非因人而異而是根據系統功能

There isn't any evidence to suggest

目前沒有任何證據顯示

that individuals have dominant sides of the brain,

個人的腦有哪一邊 特別支配某種能力

or to support the idea of a left-right split

也沒證據支持左右之分的看法

between logic and creativity.

尤其是邏輯和創造力

Some people may be particularly logical or creative,

有人可能特別有邏輯或創造力

but that has nothing to do with the sides of their brains.

但這跟腦的左右毫無關係

And even the idea of logic and creativity being at odds with each other

而且邏輯和創造力相互衝突

doesn't hold up well.

這說法也站不住腳

Solving complex math problems requires inspired creativity

解決複雜的數學問題 需要創造力的激盪

and many vibrant works of art have intricate logical frameworks.

深具巧思的藝術作品 則建立在精細的邏輯架構上

Almost every feat of creativity and logic

與邏輯和創造力有關的一舉一動

carries the mark of the whole brain functioning as one.

皆是腦部整體合一運作的結果