Here, at MosaLingua, we like to read about different studies on how languages impact our brain. After all, it is quite a big subject… which does have some strong studies behind them. A very rich subject, and a really interesting one also. So we started looking towards the impact of languages on our brain a bit more… More precisely on this question, does bilingualism delay Alzheimer’s disease? 

Very beautiful studies have proven that speaking at least two languages delays Alzheimer’s disease. So, let’s get right to it; here’s what recent studies show.

Does bilingualism delay Alzheimer's disease


Bilingualism And Aging of The Brain:
When Speaking Various Languages Helps us Not to “Age”so Fast…

Ellen Bialystok - ageing and bilingualism

Professor Ellen Bialystok*, from the University of York in Toronto, has been looking for a few years now (yeah, her too) at the impact of languages on the human brain. We have to mention that she has already published a good number of articles on this subject. In 2010, accompanied with her gang of Canadian researchers, proved that bilingualism delays the appearance of the first symptoms of Alzheimer’s disease by around five years.


Quick summary: the research team looked at the clinical records of more than 200 patients diagnosed with Alzheimer disease. The study shows that among the 200 patients, those who have known two languages nearly all their lives have a cognitive reserve which allows them to face the disease for a longer period of time before they show their first symptoms compared to monolinguals (those who speak only one language). And the symptoms we’re on about are memory loss and confusion associated with Alzheimer disease. In other words, their cognitive reserve allows them to delay the apparition of these first symptoms.


  • Alzheimer’s disease was diagnosed 3 to 4 years later in individuals in the bilingual group than those in the monolingual group
  • The first symptoms of Alzheimer’s disease appear 5 years later for bilinguals compared to monolinguals

In 2007, Professor Bialystok, with a similar team of researchers had proven (with a study of 184 patients diagnosed with probably having Alzheimer’s disease or another form of dementia) that bilingualism delays the first signs of Alzheimer’s disease by 4 years. Given in numbers, the average age in which Alzheimer’s disease was diagnosed was of 71.4 years for monolinguals and 75.5 years for bilinguals. The 2010 study had as its goal to make further study (and that was without seeing these results).


Executive Control System… an Attempt to Explain it!

That’s interesting, but how is that possible?

Professor Ellen Bialystok explains it like this: bilinguals must, in their lives, constantly make a decision arbitrate between two languages. A Franco-British speaker for example, when seeing a dog, will either say “chien” or “dog” in function of the listener. Although the listener will think nothing of it (whether dog or chien is said), the bilingual will think of both words. The executive control system of the brain is always active.


What’s this executive control system? All brains have one: it correspond the areas which allow the brain to avoid any interference when a bilingual chooses a language over another. Basically, control areas.

The studies conducted by Professor Bialystok showed that the constant use of this executive  control system of the brain is what explains why bilinguals manage certain tasks better than others, such as multitasking or quickly switching from one task to the other. Bilinguals have better control of this executive control system of the brain. And it’s this stronger usage of the system which allows them to resist Alzheimer’s disease (well, at least, its appearance).


Anything to Add?

Yes and no. The study is self-explanatory: bilingualism modifies the way our brain works, and, this having been proven, it delays the first symptoms of Alzheimer’s disease. We won’t turn around this subject any longer. However, don’t make the mistake: learning a new language (or a language that is not your mother-tongue) unfortunately does not prevent the illness a slight bit. The fact of talking daily a second language delays the apparition of the symptoms with people who are diagnosed as probably having Alzheimer’s. On the other side, the bilinguals who were diagnosed were bilinguals for years… They spoke two languages most of their lives.

At the end of the day, it’s a cool study, and its results really make us want to know even more about languages 😉


Discover other benefits of being bilingual

To find out more this fascinating topic,  you can read our article about the benefits of being bilingual: actually we covered bilingualism and in different articles…


*Ellen Bialystok, teacher and researcher at York University of Toronto and also works in partnership with Rotman Research Institute for the research center in geriatrics Baycrest.