Bi-Lingualism Can Delay Alzheimers

Ellen Bialystok is a cognitive neuroscientist who has found that bilingualism can delay the symptoms of Alzheimer's. Chris Young for The New York Times

A cognitive neuroscientist, Ellen Bialystok has spent almost 40 years learning about how bilingualism sharpens the mind. Dr. Bialystok, 62, a distinguished research professor of psychologyat York University in Toronto, was awarded a $100,000 Killam Prize last year for her contributions tosocial science. An edited version of our conversations follows.

Q.How did you begin studying bilingualism?

A.You know, I didn't start trying to find out whether bilingualism was bad or good. I did my doctoratein psychology: on how children acquire language. When I finished graduate school, in 1976, therewas a job shortage in Canada for Ph.D.'s. The only position I found was with a research projectstudying second language acquisition in schoolchildren. It wasn't my area. But it was close enough.

As a psychologist, I brought neuroscience questions to the study, like "How does the acquisition of asecond language change thought?" It was these types of questions that naturally led to thebilingualism research.

The way research works is, it takes you down a road. You then follow that road. 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. If yougave 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 sentencewas 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, wefound, manifested a cognitive system with the ability to attend to important information and ignorethe less important.

Q.How does this work?

A.There's a system in your brain, the executive control system. It's a general manager. Its job is tokeep you focused on what is relevant, while ignoring distractions. It's what makes it possible for youto hold two different things in your mind at one time and switch between them.

If you have two languages and you use them regularly, the way the brain's networks work is thatevery time you speak, both languages pop up and the executive control system has to sort througheverything and attend to what's relevant in the moment. Therefore the bilinguals use that systemmore, and that regular use makes that system more efficient.

Q.One of your most startling recent findings is that bilingualism helps forestall the symptoms of Alzheimer's disease. How did you come to learn this?

A.Bilingual older adults performed better than monolingual older adults on executive control tasks.That was very impressive because it didn't have to be that way. It could have turned out thateverybody just lost function equally as they got older.

We looked at the medical records of 400 Alzheimer's patients. On average, the bilinguals showedAlzheimer's symptoms five or six years later than those who spoke only one language. This didn'tmean that the bilinguals didn't have Alzheimer's. It meant that as the disease took root in theirbrains, they were able to continue functioning at a higher level.

Q.So high school French is useful for something other than ordering a special meal in a restaurant?

A.Sorry, no. You have to use both languages all the time. You won't get the bilingual benefit fromoccasional use.

Q.Would bilingualism help with multitasking?

A.Yes, multitasking is one of the things the executive control system handles.

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. Someof this was xenophobia.

Thanks to science, we now know that the opposite is true.

Q.Many immigrants choose not to teach their children their native language. Is this a good thing?

A.There are two major reasons people should pass their heritage language onto children.

First, it connects children to their ancestors. The second is my research: Bilingualism is good foryou. It makes brains stronger.It is brain exercise.

The New York Times

(China Daily 06/12/2011 page11)