A new study from the University of Edinburgh’s Center for Cognitive Aging and Cognitive Epidemiology suggests that knowing two or more languages may slow down the cognitive decline that normally comes with old age.

Data for the study has been collected for more than 70 years from 835 participants-- all native English speakers from Edinburgh, Scotland. The participants were first given an intelligence test in the late 1940s when they hit age 11. Then more recently, between 2008 and 2010, they were retested in their 70s.

Of the 835, almost a third knew two or more languages. This bilingual third “had significantly better cognitive abilities compared to what would be expected from their baseline.” The increased cognitive abilities were seen most strongly in the areas of reading and general intelligence. The study did not note any significant difference in the cognitive abilities of those who learned their second language during childhood and those who learned their second language during adulthood.

“These findings are of considerable practical relevance. Millions of people around the world acquire their second language later in life. Out study shows that bilingualism… may benefit the aging brain,” said Dr. Thomas Bak, lead author of the study.

However, the study also warns this could be a case of “reverse causality,” meaning that those with better cognitive function may be more likely to become bilingual, rather than bilingualism itself improving cognitive function. Either way the results are fascinating and will hopefully lead to more insight into cognitive decline.