The Bilingual Advantage

The New York Times is now running an article "The Bilingual Advantage".
Here is an excerpt.

A cognitive neuroscientist, Ellen Bialystok has spent almost 40 years learning about how bilingualism sharpens the mind. Her good news: Among other benefits, the regular use of two languages appears to delay the onset of Alzheimer’s disease symptoms. Dr. Bialystok, 62, a distinguished research professor of psychology at York University in Toronto, was awarded a $100,000 Killam Prize last year for her contributions to social science. We spoke for two hours in a Washington hotel room in February and again, more recently, by telephone. An edited version of the two conversations follows.

Q. So what exactly did you find on this unexpected road?

A. As we did our research, you could see there was a big difference in the way monolingual and bilingual children processed language. We found that if you gave 5- and 6-year-olds language problems to solve, monolingual and bilingual children knew, pretty much, the same amount of language.

But on one question, there was a difference. We asked all the children if a certain illogical sentence was grammatically correct: “Apples grow on noses.” The monolingual children couldn’t answer. They’d say, “That’s silly” and they’d stall. But the bilingual children would say, in their own words, “It’s silly, but it’s grammatically correct.” The bilinguals, we found, manifested a cognitive system with the ability to attend to important information and ignore the less important.

Q. Has the development of new neuroimaging technologies changed your work?

A. Tremendously. It used to be that we could only see what parts of the brain lit up when our subjects performed different tasks. Now, with the new technologies, we can see how all the brain structures work in accord with each other.

In terms of monolinguals and bilinguals, the big thing that we have found is that the connections are different. So we have monolinguals solving a problem, and they use X systems, but when bilinguals solve the same problem, they use others. One of the things we’ve seen is that on certain kinds of even nonverbal tests, bilingual people are faster. Why? Well, when we look in their brains through neuroimaging, it appears like they’re using a different kind of a network that might include language centers to solve a completely nonverbal problem. Their whole brain appears to rewire because of bilingualism.

Q. Bilingualism used to be considered a negative thing — at least in the United States. Is it still?

A. Until about the 1960s, the conventional wisdom was that bilingualism was a disadvantage[Sam:confuses the brain]. Some of this was xenophobia. Thanks to science, we now know that the opposite is true.

http://www.nytimes.com/2011/05/31/science/31conversation.html?src=ISMR_AP_LO_MST_FB