There are all sorts of benefits to bilingualism: kids who know two languages think faster and more creatively, for instance, and research has suggested in the past that being bilingual could fortify the brain against dementia. Now, a new study, the largest ever to look into that second connection, tracked over 600 dementia patients in Hyderabad, India, and found that those who spoke more than one language were able to delay dementia by 4.5 years.
Why does speaking more than one language have these protective effects? Having to switch between languages on a regular basis enhances “executive control:” making frequent linguistic choices – activating one language and suppressing another – is a form of practicing cognitive multitasking. Like other forms of cognitive practice – participating in continuing education, undertaking stimulating intellectual activities, engaging in physical exercise – bilingualism thus contributes to an individual’s “cognitive reserve” and wards off the effects of aging a bit longer.
Piller also points out that this new study from Hyderabad is key to confirming the link between bilingualism and dementia, as the majority of the studies previously positing the connection all came out of the same lab focusing on a Canadian population. The fact that the new research confirms the link suggests that bilingualism can be helpful in all sorts of cultural settings.
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