Dr. Thomas Bak from the University of Edinburgh is the first to examine whether learning a second language can affect the performance of the brain function later in life. His team assessed data from 835 native English speakers. The participants were given an intelligence test in 1947 at the age of 11 and were retested in their seventies between 2008 and 2010. Of the participants, 262 said that they could communicate in at least one language other than English. Of those, 195 learnt the second language before the age of 18, while 67 learned the language older.
It was found that those who spoke two or more languages had significantly better cognitive abilities in later life compared to what could be predicted from their performance in the intelligence tests at the age of 11. The strongest effects were seen in general intelligence and reading ability though verbal fluency had also improved. The effects were present in those who acquired their second language later in life as well as early.
Dr Bak said “These findings are of considerable practical relevance. Millions of people acquire their second language later in life. Our study shows that bilingualism, even when required in adulthood, may benefit the ageing brain.”
His research demonstrates that learning a second language can slow cognitive ageing (the speed at which the mental activity of the brain ages). Being bilingual could delay the onset of dementia for several years.