A study from the University of Edinburgh detected a pattern of slower mental decline among bilingual people. The longitudinal study tested 835 people born in 1936 when they were just aged 11 and then retested them in their early 70s from 2008 to 2010.

262 of the participants had learnt a language other than English, of which 195 had learnt the language before they turned 18 eyars.

Those who spoke two or more languages were found to have stronger cognitive functions as they aged than their peers.