People who speak more than one language may carry brains that look meaningfully younger than their birth certificates suggest, according to a study gaining fresh attention as it continues moving through wider science coverage this month.
Researchers led by Dr. Lucia Amoruso of the Basque Center on Cognition, Brain and Language in San Sebastián, Spain, studied 728 people from Spain's Basque region who spoke between one and four languages — various combinations of Spanish, Basque, French and English — then validated the findings in a second group of 144 people. The team used magnetoencephalography, which detects the faint magnetic fields produced by active brain cells, and applied machine learning to build a "brain aging clock" that estimates biological brain age from patterns of neural activity.
A dose-dependent effect
The results, presented at the Federation of European Neuroscience Societies Forum in Barcelona, showed the effect scaled with language count: bilingual speakers' brains looked about six years younger than expected for their age, trilingual speakers about seven years younger, and speakers of four languages about 13 years younger. People who learned a second language earlier in life, or spoke it more fluently, showed even younger-looking brains, independent of age, sex and education level.
The effect was not only related to the number of languages spoken. Higher language proficiency and earlier acquisition of a second language were also associated with more delayed brain ageing. This suggests that multilingual experience matters as a gradient: it is not simply about being bilingual or not, but about the depth and duration of language experience.
Dr. Lucia Amoruso, Basque Center on Cognition, Brain and Language
Christina Dalla, a neuroscience professor who reviewed the findings for FENS but wasn't part of the research team, called the results encouraging for anyone considering language study later in life: "This study suggests that learning a second, third or fourth language could help our brains to stay younger for longer, and the earlier we start, the better," she said, according to Neuroscience News.
The researchers caution the study is observational, not a controlled trial, so it can't prove that language learning itself slows brain aging rather than reflecting other differences — social engagement, lifestyle or general cognitive activity — between multilingual and monolingual participants. Amoruso's team says it next plans to follow participants over time to see whether the brain-age gap widens, narrows or holds steady as people grow older.
