People who've had lifelong use of two languages can help delay the onset of dementia symptoms by four years compared to those who are monolingual.

Such are the findings of a study from Rotman Research Institute at the Baycrest Research Centre for Aging and the Brain published in the February 2007 issue of Neuropsychologia (Vol.45, No.2).

According to the study's principal investigator and Professor of psychology at York University and Associate Scientist at the Rotman Research Institute at Baycrest, Dr. Ellen Bialystok:

We are pretty dazzled by the results. Our study found that speaking two languages throughout one's life appears to be associated with a delay in the onset of symptoms of dementia by four years compared to those who speak one language."

Though preliminary, the findings are nonetheless in line with a number of other recent findings about lifestyle effects on dementia and the team is already following-up on the effects of bilingualism and the onset of dementia.

So, how many languages have you been speaking in your lifetime?

Find more details from the full report.