People with two languages ‘recover twice as well from strokes’

People who speak more than one language are twice as likely to recover their cognitive abilities after a stroke compared to those who speak one language only, according to new research.

A study published in the scientific journal Stroke examined 608 stroke patients in India.

About half of the sample had only one language, while the other half spoke at least two languages fluently.

"All of them suffered strokes and all had immediate problems," Dr Thomas Bak, co-author of the research, told The Irish Times.

“But after some time, about 40 per cent of those who spoke more than one language didn’t have any cognitive problems, but only 20 per cent from monolinguists [people who speak one language] recovered fully,” he said.

“Cognitive abilities” refer to a person’s higher level thought processes, including attention, memory, language and visuospatial skills.

All of the patients in the study had the same strength of stroke and other health variables were accounted for, according to the study.

Dr Bak said having an extra language didn’t reduce the risk of having stroke, but that those that did “simply recover better”.

He said the research is part of a wider body of evidence that points to the importance of “cognitive reserve” – or brain “fitness” in damage repair.

“There is not one single study that answers it all, but if we put all the studies together, they start telling very much a coherent story,” he said.

“For people who have active mental lives with a lot of mental activities or challenging occupations intellectually, the brain is, in a way, fitter. It’s stronger.”

The study evolved out of a previous research paper, which showed that a stronger cognitive reserve can delay the onset of dementia.

With stronger and active brain, “you can compensate longer” when dementia starts to take its toll, “so it takes longer for [it] to really set in,” said Dr Bak.

Having more than one language is just one way to build up stronger connections, he said.

He also said the patients in the study were not necessarily bilingual from a young age and many would have picked up their languages passively through life experience.

Dr Bak said there is a need to replicate his study in other populations and to further investigate aspects of brain fitness and its effect on neurological problems.