會說外語優勢多：雙語讓人更聰明

SPEAKING two languages rather than just one has obvious practical benefits in an increasingly globalized world. But in recent years, scientists have begun to show that the advantages of bilingualism are even more fundamental than being able to converse with a wider range of people. Being bilingual, it turns out, makes you smarter. It can have a profound effect on your brain, improving cognitive skills not related to language and even shielding against dementia in old age.
在這個日益全球化的世界，會說兩種語言當然比只會單一語言的人有着明顯的實際好處。但近些年來，科學家們的發現開始表明，比起能夠跟不同母語的人言語交流，雙語還有很多更爲重要的優勢。事實證明，會說兩種語言會讓你更聰明。雙語機制會對你的大腦有深刻的影響，能提高與語言無關的認知能力，還能預防老年癡呆。

This view of bilingualism is remarkably different from the understanding of bilingualism through much of the 20th century. Researchers, educators and policy makers long considered a second language to be an interference, cognitively speaking, that hindered a child’s academic and intellectual development.
這種雙語觀點與20世紀以來人們對雙語的理解有着顯著差異。長期以來，研究者、教育家和決策者都認爲第二語言是一種干擾，從認知角度來說，會阻礙兒童的學業和智力的發展。

They were not wrong about the interference: there is ample evidence that in a bilingual’s brain both language systems are active even when he is using only one language, thus creating situations in which one system obstructs the other. But this interference, researchers are finding out, isn’t so much a handicap as a blessing in disguise. It forces the brain to resolve internal conflict, giving the mind a workout that strengthens its cognitive muscles.
第二語言的干擾的確存在：有充分的證據顯示，雙語者只使用其中某一種語言時，他的大腦中的兩種語言系統都很活躍，這可能會造成某一種語言系統阻礙另一種的情況。但研究者發現，這種干擾作用卻並不是不利因素，反倒會使雙語者因禍得福。這種干擾作用強迫大腦去解決內部矛盾，讓思維得到更多的鍛鍊增強認知能力。

Bilinguals, for instance, seem to be more adept than monolinguals at solving certain kinds of mental puzzles. In a 2004 study by the psychologists Ellen Bialystok and Michelle Martin-Rhee, bilingual and monolingual preschoolers were asked to sort blue circles and red squares presented on a computer screen into two digital bins — one marked with a blue square and the other marked with a red circle.
例如，雙語者在做益智遊戲時就可能表現的單一語言者更熟練。約克大學的心理學家Ellen Bialystok和Michelle Martin-Rhee在2004年進行過一項研究，要求雙語和單一語言的學齡前兒童將電腦屏幕上出現的藍圈和紅方塊分別放置到是數字箱裏：一個箱子上標記着藍方塊，另一個標記着紅圈。

In the first task, the children had to sort the shapes by color, placing blue circles in the bin marked with the blue square and red squares in the bin marked with the red circle. Both groups did this with comparable ease. Next, the children were asked to sort by shape, which was more challenging because it required placing the images in a bin marked with a conflicting color. The bilinguals were quicker at performing this task.
第一個任務要求兒童根據顏色將形狀分類：將藍圈放到標記着藍方塊的箱子裏，紅方塊放到紅圈箱子裏。兩組兒童完成起來都相對比較輕鬆。下一步要求兒童根據形狀將顏色分類，不過這個任務挑戰性比較大，要求兒童將藍圈和紅方塊分別放在標記着相反顏色的箱子裏。雙語兒童在完成這個任務時速度更快。

The collective evidence from a number of such studies suggests that the bilingual experience improves the brain’s so-called executive function — a command system that directs the attention processes that we use for planning, solving problems and performing various other mentally demanding tasks. These processes include ignoring distractions to stay focused, switching attention willfully from one thing to another and holding information in mind — like remembering a sequence of directions while driving.
許多類似的研究得到的證據足以證明，雙語經歷會提高大腦的所謂的“執行功能”：大腦的指揮系統，直接引導我們在計劃、解決問題和完成其他各種思維任務時的注意力過程。這些過程包括忽略干擾集中注意力，有意識地在兩件事情之間切換注意力，以及將信息儲存在思維中。大腦的執行功能就像是在開車時記住一系列的方位。

Why does the tussle between two simultaneously active language systems improve these aspects of cognition? Until recently, researchers thought the bilingual advantage stemmed primarily from an ability for inhibition that was honed by the exercise of suppressing one language system: this suppression, it was thought, would help train the bilingual mind to ignore distractions in other contexts. But that explanation increasingly appears to be inadequate, since studies have shown that bilinguals perform better than monolinguals even at tasks that do not require inhibition, like threading a line through an ascending series of numbers scattered randomly on a page.
爲什麼兩個同時活躍的語言系統間的角力會改善這些方面的認知能力呢？之前，研究者們一直認爲雙語的優勢主要來自在壓制一種語言系統的實戰中得到強化的抑制能力：一般認爲這種抑制力能夠幫助訓練雙語思維來忽略其他環境的干擾。不過這種解釋越發顯得不夠充分，因爲有研究證實雙語者在完成有些不需要壓制功能的任務時表現得比單一語言者更出色，例如按照升序來將隨意散落在紙上的數字串在一起。The key difference between bilinguals and monolinguals may be more basic: a heightened ability to monitor the environment. “Bilinguals have to switch languages quite often — you may talk to your father in one language and to your mother in another language,” says Albert Costa, a researcher at the University of Pompeu Fabra in Spain. “It requires keeping track of changes around you in the same way that we monitor our surroundings when driving.” In a study comparing German-Italian bilinguals with Italian monolinguals on monitoring tasks, Mr. Costa and his colleagues found that the bilingual subjects not only performed better, but they also did so with less activity in parts of the brain involved in monitoring, indicating that they were more efficient at it.
雙語者與單一語言者之間的關鍵差異可能要從更加基礎的層面來分析：一種在監測環境中得到提升的能力。 “雙語者需要頻繁切換語言，可能跟爸爸交流的是一種語言，跟媽媽說話用的可能又是另一種。” 西班牙龐培法布拉大學的研究者Albert Costa這樣表示。“這需要說話人不斷追蹤周圍的變化，跟我們開車時時刻觀察環境變化的道理一樣。Albert Costa 和同事進行過一個關於德意雙語者和意大利單語者在監測任務上的對比性研究，他們發現雙語的受試者不僅表現得更出色，而且在進行監控任務時，大腦的活動行爲更少，這表現雙語者更有效率。

The bilingual experience appears to influence the brain from infancy to old age (and there is reason to believe that it may also apply to those who learn a second language later in life).
從嬰兒時期到老年，雙語經歷都會影響着我們大腦（不過我們有理由相信這也適用於那些後天發展出雙語能力的語言者）。

In a 2009 study led by Agnes Kovacs of the International School for Advanced Studies in Trieste, Italy, 7-month-old babies exposed to two languages from birth were compared with peers raised with one language. In an initial set of trials, the infants were presented with an audio cue and then shown a puppet on one side of a screen. Both infant groups learned to look at that side of the screen in anticipation of the puppet. But in a later set of trials, when the puppet began appearing on the opposite side of the screen, the babies exposed to a bilingual environment quickly learned to switch their anticipatory gaze in the new direction while the other babies did not.
2009年在意大利的裏雅斯特國際高等教育學院，研究者Agnes Kovacs進行了這樣的研究：一組從出生就接觸兩種語言環境的7個月大的嬰兒，與他們做對比的是另一組在單一語言環境中成長的寶寶。在實驗的初期，研究者爲嬰兒提供一個音頻提示，並在屏幕的一邊展示一個布偶。兩組嬰兒都學會看着屏幕的一邊期待木偶的出現。但在實驗的後期，木偶開始出現在屏幕的另一邊。雙語環境中的寶寶們很快就學會將期待的目光轉移到新的方向，而單一語言的寶寶們則不會。

Bilingualism’s effects also extend into the twilight years. In a recent study of 44 elderly Spanish-English bilinguals, scientists led by the neuropsychologist Tamar Gollan of the University of California, San Diego, found that individuals with a higher degree of bilingualism — measured through a comparative evaluation of proficiency in each language — were more resistant than others to the onset of dementia and other symptoms of Alzheimer’s disease: the higher the degree of bilingualism, the later the age of onset.
雙語的影響會一直持續到晚年。聖地亞哥加州大學的神經心理學家近日組織44位西英雙語的老年人進行研究，結果發現個體雙語程度越高（通過對兩種語言熟練度的對比性評估測算），對癡呆和老年癡呆症的其他症狀的抵抗能力就越強：雙語程度越高，出現癡呆症的時間也越晚。

Nobody ever doubted the power of language. But who would have imagined that the words we hear and the sentences we speak might be leaving such a deep imprint?
沒人會懷疑語言的力量。但誰又能想到，我們聽到的單詞、說出的句子會對我們有如何深刻的影響呢？