Bilingualism delays dementia

Extracts from
Bilingualism Delays Onset of Dementia
By Rossella Lorenzi for Discovery News
Speaking more than one language can delay the onset of dementia by four years, according to a research on bilingualism and cognitive impairment in old age.

The mental agility required to manage two or more language systems every day throughout one's life, appears to enhance neural plasticity and enrich brain vasculature, staving off cognitive decline, Canadian researchers report in the February issue of the journal Neuropsychologia.

Dementia is associated to a gradual onset and continuing decline of higher cognitive functioning, including impairment in memory, language, visual-spatial function, judgment and abstraction.

93 people in the [study] were bilingual who had been using two languages since they were young. The bilingual group included speakers of 25 different languages, including Polish, Yiddish, German, Romanian and Hungarian.

The average age at which these patients developed dementia was 75.5 years old. Among the remaining patients, who spoke only one language, dementia began to appear at the the mean age of 71.4 years.

The four year difference remained even after considering the possible effect of cultural differences, immigration, formal education, employment and even gender as influencers in the results, the researchers said.

"What is most striking about our results is that there is no intervention available that can delay onset of symptoms by as much as four years," Bialystok told Discovery News.

Bilingualism appears to have beneficial effects if both languages are spoken regularly on a daily basis.

A 2004 study published in Nature revealed that bilinguals have greater density of grey matter in the left inferior parietal cortex compared to unilingual people.