Now, thanks to two recent studies, there is evidence that language-learning actually sharpens your brain by changing its mechanics.
One of the studies, published in the Journal of Neurolinguistics, observed strengthening neural connections between different parts of the brain in people who underwent language training. Researchers at Pennsylvania State University and the Guangdong University of Foreign Studies taught 23 people the meaning and tone of 48 Chinese language words over a period of six weeks, and used functional magnetic resonance imaging (fMRI) to measure how the subjects’ brains changed. In subjects who identified the correct tone or illustration for a word, experimenters observed that parts of the brain that hadn’t previously connected much were creating stronger paths, co-author Ping Li told Quartz.
The building of stronger connections over time between regions of the brain implies that bilingual brains are “more resistant to damage,” said Li, a professor of psychology, linguistics and information sciences and technology at Penn State. The findings support the notion that language-learning can fend off dementia.
The deeper the understanding of the language, the stronger the brain’s regional connectivity: In subjects who had been exposed to the lessons but hadn’t learned as successfully, the connections were often no better than the monolingual subjects.
Another study (pdf), from researchers at Northwestern University and the University of Houston and published in the journal Brain and Language, used fMRIs to examine the blood flow in 18 English speakers and 17 people who had been speaking both English and Spanish since childhood. The fMRI shows the blood flow to different parts of the brain, which makes it possible to see how hard someone is working to solve a problem.
For this study, researchers said a word in English, then showed the subjects an illustration of the object that word described along with other objects. The brains of bilinguals were far less taxed in choosing the right photo and better able to ignore irrelevant words that came to mind, lead author and Northwestern University communications sciences and disorders professor Viorica Marian told Quartz.
Constantly confronted with competing words from multiple languages, bilinguals become better at blocking out unnecessary distractions, Marian says. That helps explain why bilinguals tend to be better at things like multitasking and grammar.