The brains of people who learn two languages in early childhood are different from those who grew up speaking only one language. Bilingual adults have denser grey matter, that is, more nerve cells and fibers that process information; and the parts of the brain that are responsible for memory, reasoning, and planning – also known as “executive function” – are larger than in people who know only one language.
A Canadian scientist found that the difference is most pronounced in those who learned a second language before the age of 5, but adults who are extremely proficient in two or more languages have many of the same brain characteristics. Bilingual children and adults are better able to concentrate and tune out distractions, and they can switch between two tasks more readily than monolinguals.
Bilinguals maintain high executive functioning longer in life than monolinguals. This “cognitive reserve,” as scientists call it, may protect the brain from some of the physical damage that Alzheimer’s and related dementias cause. Some neuroscientists think that speaking two languages may increase blood flow to the brain and give it an oxygen boost, which keeps nerve connections healthy and is thought to help fend off the effects of dementia.
A recent study shows that being bilingual delays the onset of dementia and Alzheimer’s symptoms by an average of 4.5 years. They studied nearly 650 patients at a university memory clinic in Hyderabad, India, more than half of whom were bilingual. One of the most interesting findings is that illiterate bilinguals enjoy the same brain protection as those who can read and write. The Indian study found that bilingualism delays symptoms independent of other factors that can affect the onset of symptoms such as education, sex, or living in an urban or rural setting.
The protective effect is greatest for people who use a second language every day and are constantly having to choose between two sets of words, but any way of learning a foreign language is helpful, as long as you continue to practice it.
The current state of bilingualism
- 20% (estimated) of the United States population are bilingual (it was 11% in 1980)
- 26% of Arizonans speak another language at home
- 36% in the Phoenix metro area speak another language at home (actual percentage of bilinguals is probably considerably higher; the US Census does not ask about bilingualism specifically, so we don’t have reliable data)
- Up to 60% in Los Angeles grew up speaking two languages
- About 50% of bilinguals in the US speak English and Spanish. The other half speak everything from Native American languages to European languages, to Arabic, to Chinese, and everything in between.
It’s well known that doing brain exercises, such a crossword puzzles, makes your brain stronger. Now we have another way to strengthen it. If you don’t already speak another language, you don’t have to be left out of the benefits. Many colleges and universities offer life-long learning programs geared toward the adult brain. In addition to the medical benefits, learning a new language can be fun. You get to learn about another culture and meet people with similar interests. You probably don’t want to do crossword puzzles all day long every day, but no matter how old you are you can learn a new language and talk till the cows come home