Being bilingual provides brain protection against Alzheimer’s disease, according to a new study.
- According to the study, people with Alzheimer’s who spoke two languages had a significantly larger hippocampus than other sufferers.
- This could explain why bilinguals develop the disease later than other patients.
- Speaking more than one language is one of many ways to boost cognitive and social skills, the researchers conclude.
Bilingualism not only offers more professional opportunities. Studies have shown that it also protects against cognitive decline and delays the onset of Alzheimer’s disease by up to five years compared to people who speak only one language.
Researchers from Concordia University have shed light on the brain mechanisms that protect bilingual patients. They detailed their discovery in the journal Bilingualism: Language and Cognition.
Alzheimer’s: the hippocampus of bilinguals is larger than others
To better understand brain resilience arising from bilingualism, the Canadian team studied and compared the brains of people speaking one or two languages through imaging. Some of the participants were neurologically healthy while others had mild cognitive impairment or had been diagnosed with Alzheimer’s disease.
Scientists found that the hippocampus of bilinguals with Alzheimer’s disease was significantly larger than that of monolingual people. “Brain material was most prominent in the hippocampus, which is the main region of the brain responsible for learning and memory – and one of the most damaged in Alzheimer’s”explains lead author and doctoral student Kristina Coulter.
By studying the brain characteristics of bilingual and monolingual volunteers, the researchers found that while hippocampal atrophy was visible in monolingual people with mild cognitive impairment or Alzheimer’s disease, the volume of the hippocampus did not did not change in bilingual people throughout the progression of neurodegenerative pathology.
“In the bilingual group, brain volume in the region affected by Alzheimer’s disease was identical in healthy older adults, in those who were at one of the two stages of risk, and in those who had Alzheimer’s disease. of Alzheimer’s disease, explains Kristina Coulter. There could therefore be a form of brain maintenance linked to bilingualism.
Brain: bilingualism stimulates cognitive and social faculties
In their press releasethe researchers point out that brain resilience, which protects against cognitive decline, is based on 3 elements:
The first is “brain maintenance.” This is the continued ability of the brain to maintain its shape and function as it ages. “It is believed that mental stimulation, such as that provided by bilingualism, as well as a healthy diet, regular physical activity, quality sleep and good sensory health contribute to preventing brain deterioration”add the authors.
They then cite “cognitive reserve”, or the brain’s ability to maintain its functions by other means when it has suffered damage or shrinkage linked to aging.
The third element is “brain reserve”, or the size and structure of the brain. “Brains with greater reserve can maintain normal functions due to the additional volume or capacity of brain matter”indicate the researchers. During their work, they did not find brain reserve associated with bilingualism in areas of the brain linked to language, nor cognitive reserve in areas of the brain associated with Alzheimer’s disease.
“Speaking more than one language is one of the many ways to stimulate cognitive and social skills, and therefore contribute to brain health,” concludes Natalie Phillips. Our study is unique because it allows us to examine the potential effects of bilingualism on brain structure at all stages of dementia risk, whether in cognitively normal people, those at higher risk of developing Alzheimer’s disease, or those with the disease .”
Kristina Coulter and Natalie Phillips plan to continue their research to see if similar beneficial effects are seen with polyglots.
