Bilingualism Delays Onset of Dementia

People who are fully bilingual and speak both languages every day for most of their lives can delay the onset of dementia by up to four years compared with those who only know one language, Canadian scientists said on Friday. Researchers said the extra effort involved in using more than one language appeared to boost blood supply to the brain and ensure nerve connections remained healthy - two factors thought to help fight off dementia.
Bialystok's team focused on 184 elderly patients with signs of dementia who attended a Toronto memory clinic between 2002 and 2005. Of the group, 91 spoke only one language while 93 were bilingual. "The researchers determined that the mean age of onset of dementia symptoms in the monolingual group was 71.4 years, while the bilingual group was 75.5 years," the statement said. "This difference remained even after considering the possible effect of cultural differences, immigration, formal education, employment and even gender as (influences) in the results," it added.
Bialystok stressed that bilingualism helped delay the start of dementia rather than preventing it altogether. Psychologist Fergus Craik, another member of the team, said the data showed that being fully bilingual had "a huge protective effect" against the onset of dementia but he added that the study was still a preliminary finding. The team plans more research into the beneficial side-effects of bilingualism.