Researchers from Canada's Concordia University have analyzed brain scans from both multilingual and monolingual people, all of whom were previously diagnosed with either Alzheimer's disease or mild cognitive impairment (MCI). Their conclusion: knowing a second language may help offset the effects of degenerative brain disorders.

Led by Prof. Natalie Phillips, the team studied whole-brain MRIs from 94 individuals – 34 monolingual MCI patients, 34 multilingual MCI patients, 13 monolingual Alzheimer's patients and 13 multilingual Alzheimer's patients.

The scientists were particularly interested in language and cognition control areas in the frontal regions of the brain, along with medial temporal lobe structures associated with memory. These areas are known to atrophy in MCI and Alzheimer's patients.

What they found was that in the multilingual patients, the tissue thickness and density in these regions was greater than it was in the monolingual patients.

"Our results contribute to research that indicates that speaking more than one language is one of a number of lifestyle factors that contributes to cognitive reserve," says Phillips. "They support the notion that multilingualism and its associated cognitive and sociocultural benefits are associated with brain plasticity."

A paper on the research was recently published in the journal Neuropsychologia.