A study conducted by researchers at the Toronto based Baycrest Centre for Geriatric Care’s Rotman Research Institute, a premier international centre for the study of human brain function, suggests that speaking two languages can help delay the onset of Alzheimer's symptoms by as long as five years. The researchers came to the conclusion after examined clinical records of 211 patients diagnosed with Alzheimer's disease. There are currently no drug treatments that can delay the symptoms of Alzheimer's.
The study replicated findings from a 2007 study led by Ellen Bialystok of York University that found bilingual dementia patients experienced a delayed onset of their symptoms compared to monolingual patients. It found that bilingual patients delayed the onset of their symptoms by four years compared to monolingual patients.
The subjects' brains still showed deterioration from Alzheimer's regardless of language skills, however bilingualism appeared to have delayed symptoms such as memory loss, confusion, and difficulties with problem-solving and planning.
Ellen Bialystok, professor of psychology in York’s Faculty of Health and associate scientist at the Rotman Research Institute, said, “All the patients in the study had been diagnosed with Alzheimer’s, so clearly bilingualism does not prevent the onset of dementia. Instead, our results show that people who have been lifelong bilinguals have built up a cognitive reserve that allows them to cope with the disease for a longer period of time before showing symptoms.”
While the brains of bilingual patients did show deterioration, researchers believe that the use of more than one language equips them with compensatory skills that keep symptoms like memory loss and confusion in check.
Both studies point to the need to treat bilingualism as an important tool for healthy aging, along with exercise, diet, and other lifestyle choices. Now, there is a good reason to encourage people in multicultural societies to keep speaking their native tongue and pass it along to their children.