A new study presented at the Federation of European Neuroscience Societies (FENS) conference in Barcelona finds that people who speak multiple languages show signs of slower brain ageing than those who speak only one. Researchers used magnetoencephalography to examine brain activity patterns and applied AI methods to estimate a “brain ageing clock” based on expected brain connectivity for a given age. In one analysis involving neuroimaging data from 728 participants with different language backgrounds, the investigators compared results across levels of multilingualism. A follow-up comparison used brain scans of 144 additional participants who spoke varying numbers of languages. Across the findings, participants who speak two languages appear to have brains that look about six years younger than monolingual speakers; the apparent difference increases for those who speak three or four languages, reaching roughly 13 years younger for people speaking four languages. The researchers also report that higher language proficiency and earlier acquisition of a second language are associated with more delayed brain ageing, suggesting the relationship may depend on the depth and duration of multilingual experience. Independent experts quoted by media outlets say effortful learning and other lifestyle factors also influence brain health as people age.