Scientists at Northwestern University in the US have found that speaking two languages can enhance brain function, acting as a mental workout that fine-tunes the mind. Their research, published in the Proceedings of the National Academy of Sciences, provides biological evidence of the cognitive benefits of bilingualism.
The study monitored brain responses in 48 healthy student volunteers, 23 of whom were bilingual, using scalp electrodes to trace brainwave patterns. In quiet conditions, both the bilingual and English-only groups responded similarly to sounds. However, against a backdrop of noisy chatter, the bilingual group demonstrated superior sound processing, better able to focus on a speaker's voice and filter out background distractions.
These differences were visible in the brain, with bilingual individuals showing heightened brainstem responses. Lead researcher Prof Nina Kraus explained: 'The bilingual's enhanced experience with sound results in an auditory system that is highly efficient, flexible and focused in its automatic sound processing, especially in challenging or novel listening conditions.'
Co-author Viorica Marian added: 'People do crossword puzzles and other activities to keep their minds sharp. But the advantages we've discovered in dual language speakers come automatically simply from knowing and using two languages.' The benefits include improved attention, inhibition and encoding of sound, similar to gains seen in musicians during rehearsals. Past research has also suggested that bilingualism may help ward off dementia.
