Over the past several years, cognitive scientists and their kin have amassed a body of work around the “bilingual advantage.” Time and again, bilinguals do better on measures of “cognitive control” and “executive functioning” — the processes by which your brain sidesteps knee-jerk, automatic responses to stimuli — than their single-tongued peers.
With a recent paper in the Journal of Neurolinguistics, the neural mechanisms that underlie this advantage are coming to light. Basically, spending decades parsing different tongues trains the brain to be really awesome at cutting through distraction, and doing so in resource-efficient ways. Not only that, but this bilingual way of processing appears to be preserved in old age in a way that the monolingual isn’t.
The research team, led by Pierre Berroir at the University of Montreal, recruited ten monolingual French speakers and ten bilingual French-English speakers, who were about 74 years old on average.
After taking several assessments for cognitive and emotional health, the participants completed the “Simon task,” a simple video game where blue or yellow squares show up either on the left or right sides of a black screen. The participant is supposed to hit the corresponding key on the left side of the keyboard when the blue square comes up (like “A,” on a standard QWERTY keyboard) and the corresponding key on the right side of the keyboard with the yellow square (like L). In “congruent” conditions, the square shows up on the side of the key it’s near, while in “incongruent” the situation is flipped — so you’d have a blue square show up on the right side of the screen, and have to hit the letter A on the left side of your keyboard. If this sounds confusing, that’s because it is. It’s kind of like Whack-A-Mole, and you can play a version here.
The experimenters found that even if you’re well into your 70s, speaking a second language makes it easier to navigate thickets of mixed signals such as these. “The results of the present work suggest that lifelong juggling with two languages in competition impacts the brain at a network level, and they provide information about the role of experience as a source of cognitive efficiency,” the authors write.
Bilinguals actually needed fewer areas of the brain to be active to get the task done, and did so quickly — speaking to the efficiency that the bilingual brain develops over time. As well, monolinguals relied on areas of the brain — right middle frontal gyrus — that’s super vulnerable to diseases of aging, which may be another reason the bilingual brain is better suited to tricky tasks.
While 20 participants doesn’t make for the most robust sample size, the study shows just how much your daily habits, stretched out over decades, shape the very structures of your brain.