Delaying Alzheimer's Symptoms with Bilingualism
If you took French or Spanish in high school, now's the time to brush up on those verb tenses. A study at UCLA has found that people who are proficient in two or more languages can stall the onset of Alzheimer's disease symptoms for about four years, compared with those who only speak one language.
The study concerned 253 patients from the general area of LA county. The most common native languages were Spanish and Farsi, along with 13 others.
If you're wondering how bilingualism could possibly prevent Alzheimer's, you're right to wonder. It doesn't. Instead of stopping the brain damage, the research indicates that speaking multiple languages builds up a "cognitive reserve" which helps the brain continue to function despite the impairment. “They are getting the disease, but they are not expressing it with clinical impairment or symptoms until further on,” explained study leader Mario Mendez, MD, PhD, Director of Neurobehavior at the VA Greater Los Angeles and Professor of Neurology and Psychiatry at David Geffen School of Medicine at UCLA.
Where does this cognitive reserve come from? When a person is fluent in more than one language, expressing oneself requires an additional degree of effort, as the speaker or writer must actively select one language while suppressing the other. This instantaneous decision-making, a form of code-switching, occurs in the frontal regions of the brain, which also handles a variety of executive functions, including working memory and self-control. It's believed that all the language-juggling helps the brain function in the decline by building up the whole network.
What's interesting to note is that, when the dementia did manifest in the brains of the bilingual study subjects, they tended to switch back to using their native language full-time. “Are they having problems with inhibiting the intrusion of their first language?” Mendez said.
Also of note: the bilingual subjects were not bilingual from birth. Mendez's patients learned English when they arrived in the United States, years after learning their first language. In contrast to what you might have heard about how it's absolutely crucial to pick up a second language while you're young, Mendez said, “Your proficiency of use of the second language is more important than whether you learned it before age 5."
Acquiring a second language late in life can come with considerable struggle. Continuing to effortfully select the correct words in the correct language for each given situation can be a struggle as well. However, the Mendez study suggests that this struggle comes with a notable reward. So while we in the U.S. wait out our quarantine, you might as well fire up Duolingo.