Knowing more than one language delays Alzheimers: Study

The study showed that bilingual Alzheimers patients developed symptoms several years later than those who spoke only one language.

The US studys findings contradict popular assumptions that switching between two or more languages has a confusing tower of Babel effect.

Professor Ellen Bialystok from York University in Toronto,Canada,looked at more than 200 Alzheimers patients,half of whom were bilingual.

Infants raised bilingual from birth can distinguish not only between their two native tongues but between two languages theyve never been exposed to,just by watching adults speak without hearing what they say,said psychologist Janet Werker of the University of British Columbia.

Bilingual infants are able to keep their languages distinct from birth and may develop an increased sensitivity to voice and face cues for different languages, Werker said.

The American Association for the Advancement of Science annual meeting in Washington heard that bilingual speakers tend to outperform monolinguals in certain mental abilities,such as editing out irrelevant information and focusing on what is actually important.

Judith Kroll,psychology professor at the University of Maryland,said the findings contradicted previous ideas that bilingualism somehow hindered cognitive development.

The received wisdom was that bilingualism created confusion,especially in children, she said. The belief was that people who could speak two or more languages had difficulty using either.

In fact,exactly the opposite is true.

But the most striking evidence of the benefits of bilingualism came at the other end of life.

Professor Bialystok said that her study of 450 Canadian Alzheimers patients half monolingual and half bilingual proved that speaking two languages through life had a dramatic protective effect against dementia.

In patients who were matched for cognitive level,education,job history and immigration background,bilingualism delayed the onset of Alzheimers symptoms by four to five years on an average.

It seems to be adding to peoples cognitive reserve,like other social,mental and physical activities that give some protection against dementia in older people who maintain an active lifestyle, said Professor Bialystok.