勵志演講 雙語能力對大腦的益處驚人

¿Hablas español? Parlez-vous français? ni hui shuo zhong wen ma? If you answered “si”,”oui” or ”hui” and you are watching this in English, chances are you belong to the world bilingual and multilingual majority. And besides having an easier time traveling, or watching movies without subtitles, knowing two or more languages means that your brain may actually look and work differently than those of your monolingual friends. So what does it really mean to know a language?

你會說中文嗎？如果你能回答“si”、“oui”或者“是的”，而且能看懂這個英文短片，那麼你就跟世界上很多人一樣、具備雙語能力或是多語能力。除了旅遊時溝通比較方便、看電影不需要字幕這些好處之外，通曉兩種或者三種以上的語言，意味着你的大腦在結構上或運作上與你那些單一語言的朋友有着明顯的不同。所以到底什麼才能算通曉一門語言呢？

Language ability is typically measured in two active parts, speaking and writing, and two passive parts, listening and reading. While a balanced bilingual has near equal abilities across the board in two languages, most bilinguals around the world know and use their languages in vary proportions. And depending on their situation and how they acquired each language, they can be classified into three general types.

衡量語言能力，主要包含兩個主動部分——說和寫，和兩個被動部分——聽和讀。雖然一個出色的雙語者對於兩種語言都有着相近的使用能力，但是大多數的雙語者對兩個語種的認知和使用能力是有差異的。根據個人所處的環境以及他們具體學語言的方法，雙語者通常可以分成三類。

For example, let’s take Gabriella, whose family immigrates to the US from Peru when she was two-years old. As a compound bilingual, Gabriella develops two linguistic codes simultaneously, with a single set of concepts, learning both English and Spanish as she begins to process the world around her. Her teenage brother, on the other hand, might be a coordinate bilingual, working with two sets of concepts, learning English in school, while continuing to speak Spanish at home and with friends.

舉個例子來說，Gabriella在兩歲時跟着家人由祕魯移民到美國。她屬於複合型雙語者，Gabriella在剛接觸這個世界時就同時學英語和西班牙語，所以給她一個概念、她的大腦就能同時喚起兩種語言信號。她有一個十幾歲的哥哥，則屬於協調型雙語使用者，他運用兩種不同的概念，一方面在學校學習英語，另一方面用西班牙語和家人、朋友交流。

Finally, Gabriella’s parents are likely to be subordinate bilinguals who learned a secondary language by filtering it through their primary language.

最後，Gabriella的父母，則屬於從屬型雙語者。當他們學習外語（英語）時，需要通過母語進行翻譯再進行學習。

Because all types of bilingual people can become fully proficient in a language regardless of accent and pronunciation, the difference may not be apparent to be a casual observer. But recent advances in imaging technology have given neurolinguists a glimpse into how specific aspects of language learning affect the bilingual brain.

如果不考慮口音和發音問題，這三種類型的雙語者至少都算能精通一門語言。因此，一般人很難發現這三種類型的差異。然而現在，由於大腦成像技術不斷進步，神經語言學家能夠知道語言學習對雙語使用者的大腦產生什麼樣的影響。

It’s well known that the brain’s left hemisphere is more dominant and analytical in logical processes, while the right hemisphere is more active in emotional and social ones, though this is a matter of degree, not an absolute split.

大家都知道，大腦的左半球是掌管數據和邏輯分析的，而大腦的右半球則掌管情感與社交，但這並不是絕對的、只是比例多少的問題。

The fact that language involves both types of functions while lateralization develops gradually with age, has lead to the critical period hypothesis. According to this theory, children learn languages more easily because the plasticity of their developing brains let them use both hemispheres in language acquisition, while in most adults, language is lateralized to one hemisphere, usually the left.

語言同時包括了左腦和右腦的功能，而隨着年齡的增長，大腦的功能會逐漸側重其中的一邊，語言學習的關鍵時期假說就是由這個事實引申出來的。根據這個理論，兒童學習語言更容易，是因爲他們的大腦仍在發展、可塑性更強，他們可以同時調用左右兩邊大腦的機能來學習語言；然而多數成年人只通過大腦的一邊（通常是左腦）學習語言。

If this is true, learning a language in childhood may give you a more holistic grasp of its social and emotional contexts. Conversely, recent research showed that people who learned a second language in adulthood exhibit less emotional bias and a more rational approach when confronting problems in the second language than their native one.

如果這個假說是真的，那麼在兒童時期學習語言可以讓你對其社會和情感內涵有着更整體的把握。另一方面，近期的研究表明，成年人學習外語時的情緒性偏見沒那麼多，同時相比於母語環境，他們在外語環境中遇到問題時也更爲理性。

But regardless of when you acquire additional languages, being multilingual gives your brain some remarkable advantages. Some of these are even visible, such higher density of the gray matter that contains most of your brain’s neurons and synapses, and more activity in certain regions when engaging a second language. The heightened workout a bilingual brain receives throughout its life can also help delay the onset of diseases, like Alzheimers and Dementia by as much as 5 years.

無論如何，當你學習一門新的語言時，多語能力都會給你的大腦帶來明顯的好處。有些好處甚至是可視化的，比如大腦灰白質的密度增加，那裏包含了大多數的神經元和突觸，而且在學習外語時，大腦的部分區域會變得更加活躍。雙語者的大腦可以持續不斷地接收強化訓練，這能讓一些病症（如阿茲海默癡呆症和失智症）的發作推遲至5年以後。

The idea of major cognitive benefits to bilingualism may seem intuitive now, but it would have surprised earlier experts. Before the 1960s, bilingualism was considered a handicap that slowed the child’s development by forcing them to spend them too much energy distinguishing between languages, a view based largely on flawed studies.

雙語能力對認知能力的有所幫助在現代來看是很好理解的，但是過去的專家一定會對這個觀點大吃一驚。在1960年之前，人們認爲使用雙語對於兒童的成長來說是一種障礙，因爲這需要兒童花費精力去分辨別不同語言，這種觀點的產生源自有瑕疵的研究方法。

And while a more recent study did show that reaction times and errors increase for some bilingual students in cross-language tests, it also showed that the effort and attention needed to switch between languages triggered more activity in, and potentially strengthened, the dorsolateral prefrontal cortex. This is the part of brain that plays a large role in executive function, problem solving, switching between tasks, and focusing while filtering out irrelevant information.

最新的研究的確顯示，在跨語言測驗當中，使用雙語的學生的反應時間與錯誤次數增加了；同時也表明，學生需要花費更多的努力和注意力進行語言的轉換，這也使得前額葉腦區更加活躍、進而強化其機能。前額葉腦區主要影響執行、解決問題、多任務轉換、集中注意力、排除無關信息的能力。

So, while bilingual may not necessarily make you smarter, it does make your brain more healthy, complex and actively engaged, and even if you didn’t have the good fortune of learning a second language like a child, it’s never too late to do yourself a favor and make the linguistic leap from, ”Hello,” to “Hola”, ”Bonjour” or “ninhao’s” because when it comes to our brains a little exercise can go a long way.

雖然學習雙語不一定能讓你更聰明，但是它可以讓你的大腦更加健康、多元和活躍。即使你在年幼時沒有機會學習第二語言，但是現在學習永遠不會太晚。從現在開始學一門外語吧，把“hello”轉換成“Hola”、“Bonjour”、“你好”(本文作者母語爲英語)等外語問候，即使只是小小的訓練，也能對大腦有所幫助。