Bilingualism May Stave Off Dementia, Study Suggests

It is possible to find friends in unexpected places by speaking two languages. According to a new study, bilingualism could also have other benefits such as improved memory later in life.

Researchers in Germany studied hundreds of elderly patients and found that those patients who used two languages every day from a young child scored higher on learning, memory, self-control, and language tests than patients who only spoke one language.

The findings published in the April edition of the journal Neurobiology of Aging add to the two decades of research that suggests bilingualism can protect against dementia and cognitive decline among older people.

Miguel Arce Renteria is a neuropsychologist from Columbia University, who wasn't involved in the study. He said: "It is promising that they report early and middle life bilingualism can have a positive effect on cognitive health later in life." This would be in line with existing literature.

Scientists have made progress in recent years to better understand bilingualism, but not all of their findings are consistent. Those who are fluent in two languages have dementia at a younger age than those who only speak one. Other research, however, has not shown any clear benefits from bilingualism.

Scientists hypothesize, based on the fact that bilingual people can switch between two languages fluidly, that they might be able use similar strategies to develop other skills, such as managing emotions, multitasking and self-control, that will help them delay dementia.

The study included 746 participants aged 59-76. Approximately 40 percent of volunteers did not have memory problems. The other patients were at memory clinics who had suffered confusion or memory loss.

All participants were assessed on various vocabulary, memory and attention tasks. For example, they were asked to remember previously named objects and to spell backwards, follow three-part instructions and copy designs.

The volunteers who used a second-language daily between the ages of 13 and 30 (or between 30 and 65) scored higher on tests measuring language, memory and attention.

Boon Lead Tea, a neurosurgeon at the University of California in San Francisco who wasn't involved in the study, described the approach as unique. She said that the large sample size of the study would allow the researchers to generate novel results. For example, they could determine if the age at which someone acquired each language affected cognition later in life.

She warned, however, the study focused only on one aspect: using two language every day for a long period of time. It is possible that the positive effects on cognition are due to another factor. For example, the age when the two languages have been encoded in memory or the demographics or life experiences of the bilingual people.

Experts agreed that results could have been different had researchers asked volunteers whether they spoke a second or third language every day, as opposed to once a week.

Esti Blanco Elorrieta is a language researcher from Harvard University. She said: "I don't think that there is a universal definition of bilingualism, and there never will be, because it is such a broad spectrum."

In future research, it's important to examine the benefits of bilingualism in a broader sense, according to Dr. Blanco-Elorrieta. She speaks Basque as well as English, German, and Spanish.

She said that the advantage of being bi-lingual is not in these milliseconds. "I believe that being bilingual means being able communicate with two different cultures and two different ways of looking at the world.