- As we age, our cognitive abilities tend to decline
- Recent research shows that bilingualism could contribute to the mind's ability to resist damage
- It can also slow down the onset of symptoms of dementia
In the past, there have been many myths about bilingualism being disruptive, with some believing it can delay a child’s development or even cause confusion during language learning.
However, emerging evidence indicates that bilingualism proves to have many cognitive benefits.
Recent research shows that lifelong bilingualism may contribute to cognitive reserve, which refers to the mind’s ability to resist damage.
Lower prevalence of dementia
A team of Spanish researchers conducted a study to investigate how active bilingualism (as opposed to speaking only one language) would affect cognitive decline associated with ageing.
"We have seen that the prevalence of dementia in countries where more than one language is spoken is 50% lower than in regions where the population uses only one language to communicate,” according to co-author, Professor Marco Calabria.
The researchers noted that although other studies have found that bilingualism is beneficial for cognitive reserve, they have failed to define the exact degree of bilingualism.
For this reason, the team chose to define active bilingualism as “the continuous use of the two languages as opposed to second language exposition only”, and constructed a scale.
They also considered other variables to define this scale of bilingualism, such as the age at which the second language was acquired, how the languages were used, as well as the contexts in which the languages were used.
Two languages are better than one
To test their hypothesis, the scientists collected data from Barcelona, basing their choice of location on the local use of both Spanish and Catalan. Participants were recruited from four hospitals, including 63 healthy individuals, 68 with Alzheimer’s and 135 with mild cognitive impairment (such as memory loss).
These participants were tested for their proficiency in each language in order to establish their level of bilingualism, and they were also asked to perform cognitive tasks.
Ageing bilinguals have cognitive advantage
According to professor Calabria, they "saw that people with a higher degree of bilingualism were given a diagnosis of mild cognitive impairment later than people who were passively bilingual".
The researchers explained that a possible reason for this is due to the brain’s ability to alternate between two languages (in active bilinguals), and when the brain encounters neurodegenerative diseases, it uses this ability to its advantage.
Professor Calabria explained further: “When something does not work properly as a result of the disease, the brain has efficient alternative systems to solve it, thanks to being bilingual.”
He went on to say that the more an individual uses two languages (and the better their skill), the more it contributes to cognitive reserve.
Findings of the study also indicated that active bilingualism delays the onset of symptoms of mild cognitive impairment and Alzheimer’s disease.