单项选择题

The Bilingual Brain
When Karl Kim immigrated to the United States from Korea as a teenager, he had a hard time learningEnglish. Now he speaks it fluently, and he had a unique opportunity to see how our brains adapt to a secondlanguage. As a graduate student, Kim worked in the lab of Joy Hirsch, a neuroscientist in New York. Theirwork led to an important discovery. They found evidence that children and adults don't use the same parts ofthe brain when they learn a second language. The researchers used an instrument called an MRI( magnetic resonance imaging) scanner to study thebrains of two groups of bilingual people. One group consisted of those who had learned a second language aschildren. The other consisted of people who, like Kim, learned their second language later in life. People fromboth groups were placed inside the MRI scanner. This allowed Kim and Hirsch to see which parts of the brainwere getting more blood and were more active. They asked people from both groups to think about what theyhad done the day before, first in one language and then the other. They couldn't speak out loud because anymovement would disrupt the scanning. Kim and Hirsch looked specifically at two language centers in the brain - Broca's area, which is believedto control speech production, and Wernicke's area, which is thought to process meaning. Kim and Hirsch foundthat both groups of people used the same part of Wernicke's area no matter what language they were speaking. But their use of Broca's area was different. People who learned a second language as children used the same region in Broca's area for both theirfirst and second languages. People who learned a second language later in life used a different part of Broca'sarea for their second language. How does Hirsch explain this difference? Hirsch believes that when language is first being programmed in young children, their brains may mix the sounds and structures of all languages inthe same area. Once that programming is complete, the processing of a new language must be taken over by adifferent part of the brain. A second possibility is simply that we may acquire languages differently as children than we do as adults.Hirsch thinks that mothers teach a baby to speak by using different methods involving touch, sound, and sight.And that is very different from learning a language in a high school or college class.

Kad Kim’s study showed that（）

点击查看答案&解析