Bilingualism delays onset of Alzheimer’s symptoms
A study confirms the dramatic effect of being bilingual, with bilingual speakers being diagnosed with Alzheimer’s more than 4 years later than monoglots.
Clinical records of 211 patients diagnosed with probable Alzheimer’s disease have revealed that those who have spoken two or more languages consistently over many years experienced a delay in the onset of their symptoms by as much as five years. It’s thought that lifelong bilingualism may contribute to cognitive reserve in the brain, enabling it to compensate for memory loss, confusion, and difficulties with problem-solving and planning.
Of the 211 patients of the Sam and Ida Ross Memory Clinic at Baycrest, 102 patients were classified as bilingual and 109 as monolingual. Bilingual patients had been diagnosed with Alzheimer’s 4.3 years later than the monolingual patients on average, and had reported the onset of symptoms 5.1 years later. The groups were equivalent on measures of cognitive and occupational level, there was no apparent effect of immigration status, and there were no gender differences.
The findings confirm an earlier study from the same researchers, from the clinical records of 184 patients diagnosed with probable Alzheimer’s and other forms of dementia.
Bilingualism has protective effect in delaying onset of dementia
An analysis of 184 people with dementia (132 were diagnosed with Alzheimer’s; the remaining 52 with other dementias) found that the mean age of onset of dementia symptoms in the 91 monolingual patients was 71.4 years, while for the 93 bilingual patients it was 75.5 years — a very significant difference. This difference remained even after considering the possible effect of cultural differences, immigration, formal education, employment and even gender as influencers in the results.
Being fluent in two languages may help keep the brain sharper for longer
A study of 104 people aged between 30 and 88 has found that those who were fluent in two languages rather than just one were sharper mentally. Those fluent in two languages responded faster on tasks assumed to place demands on working memory, compared to those who were fluent in just English, at all age groups. This is consistent with the theory that constant management of 2 competing languages enhances executive functions. Bilingual volunteers were also much less likely to suffer from the mental decline associated with old age. The finding is consistent with other research suggesting that mental activity helps in protecting older adults from mental decline. The participants were all middle class, and educated to degree level. Half of the volunteers came from Canada and spoke only English. The other half came from India and were fluent in both English and Tamil.