会说外语优势多：双语让人更聪明

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.
双语者与单一语言者之间的关键差异可能要从更加基础的层面来分析：一种在监测环境中得到提升的能力。 “双语者需要频繁切换语言，可能跟爸爸交流的是一种语言，跟妈妈说话用的可能又是另一种。” 西班牙庞培法布拉大学的研究者Albert Costa这样表示。“这需要说话人不断追踪周围的变化，跟我们开车时时刻观察环境变化的道理一样。Albert Costa 和同事进行过一个关于德意双语者和意大利单语者在监测任务上的对比性研究，他们发现双语的受试者不仅表现得更出色，而且在进行监控任务时，大脑的活动行为更少，这表现双语者更有效率。

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).
从婴儿时期到老年，双语经历都会影响着我们大脑（不过我们有理由相信这也适用于那些后天发展出双语能力的语言者）。

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年在意大利的里雅斯特国际高等教育学院，研究者Agnes Kovacs进行了这样的研究：一组从出生就接触两种语言环境的7个月大的婴儿，与他们做对比的是另一组在单一语言环境中成长的宝宝。在实验的初期，研究者为婴儿提供一个音频提示，并在屏幕的一边展示一个布偶。两组婴儿都学会看着屏幕的一边期待木偶的出现。但在实验的后期，木偶开始出现在屏幕的另一边。双语环境中的宝宝们很快就学会将期待的目光转移到新的方向，而单一语言的宝宝们则不会。

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.
双语的影响会一直持续到晚年。圣地亚哥加州大学的神经心理学家近日组织44位西英双语的老年人进行研究，结果发现个体双语程度越高（通过对两种语言熟练度的对比性评估测算），对痴呆和老年痴呆症的其他症状的抵抗能力就越强：双语程度越高，出现痴呆症的时间也越晚。

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?
没人会怀疑语言的力量。但谁又能想到，我们听到的单词、说出的句子会对我们有如何深刻的影响呢？