Living in the United States warps our minds—but not in the way you might think. Being able to speak both English and Spanish fundamentally changes our brains and perhaps, as some studies have shown, improves our ability to fight off Alzheimer’s disease.
On the surface, a bilingual brain doesn’t look any different from that of a monolingual. But using new imaging technology, researchers have been able to get a closer, more detailed look at the brain than ever before and have made some striking discoveries.
People who are able to speak two languages—like 44% of U.S. Hispanics—have more gray matter (grayish-brown brain cells linked to intelligence) in a region of the brain that controls speech and reading. The younger you are when you learn a second language, and the more proficient you are at speaking and understanding it, the more gray matter you’ll develop.
“These results suggest that the brain itself is different in people who speak more than one language, possibly a result of change in response to environmental demands,” said Dr. Tamar Gollan, Hispanic program coordinator at the University of California, San Diego’s (UCSD) Shiley-Marcos Alzheimer’s Disease Research Center.
But what sort of effect does denser gray matter have on the health and function of our brains?
According to Dr. Douglas Galasko, interim director of the UCSD Shiley-Marcos Alzheimer’s Disease Research Center, “The benefit of a thicker or more richly connected brain region is that it could carry out more complicated functions more efficiently.”
This, in turn, could help the bilingual brain ward off the effects of aging, including the development of Alzheimer’s.
Bilingualism and Alzheimer’s
A few years ago, researchers from York University and the Rotman Research Institute, in Toronto, reported that bilingual immigrants are diagnosed with Alzheimer’s disease, on average, 4.1 years later than monolinguals. The researchers speculated this was due to the build up of a “cognitive reserve.”
Speaking a foreign language, doing Sudoku puzzles and reading Gabriel García Márquez are all different ways of exercising the mind and building up a cognitive reserve. According to researchers, this reserve could counteract the losses associated with aging and Alzheimer’s—allowing the brain to function normally even when it has been damaged.
“The effect may be stronger in people who speak more than two languages, and in people who regularly use a language that is not spoken by the majority of people in their surroundings,” Dr. Gollan said. However, she still doesn’t know if bilingualism is the cause of a healthier brain or an effect.
“We are not sure if bilingualism itself delays Alzheimer’s or if people who have the ability to become bilingual (or multilingual) start out with a better ability to function in the face of brain injury,” Dr. Gollan explained.
Testing bilinguals for Alzheimer’s disease
Speaking more than one language does not safeguard everyone from developing Alzheimer’s. Currently there are about 200,000 Hispanics living with Alzheimer’s in the U.S., and this number is estimated to increase to 1.3 million by 2050, according to the Alzheimer’s Association.
For those bilingual Hispanics with memory-related issues, speaking both English and Spanish can actually hinder their diagnosis. Currently Alzheimer’s is diagnosed using a series of language-based tests that are not really suited for bilinguals. In fact, according to Dr. Gollan’s research, “healthy young bilinguals sometimes produce a pattern of test results that in some ways resemble patterns seen in monolinguals with Alzheimer’s.”
This has lead American neuropsychologists to wonder how they should test Hispanic bilinguals with suspected Alzheimer’s—in English? In Spanish? Or both?
“If you allow bilinguals to use words in both languages, this sometimes improves test-performance,” Dr. Gollan said. “However, it may also obscure differences between those who have Alzheimer’s and those who do not, and this is counter-productive if the goal is to figure out who has Alzheimer’s.”
Dr. Gollan and her team are looking for ways to fix this problem, but to this day there is no solution. Dr. Gollan, however, recommends: “If you suspect you have memory difficulty, you need to find a neuropsychologist with expertise and knowledge about how to assess bilinguals. You should be tested mostly in whichever language you think is easier for you, and with some measures of your bilingual language history and dual-language skills. Without this information it will be very difficult to arrive at an accurate diagnosis.”
Coffeeshop Cubicle 