From VOA Learning English, this is the Health Report.
New research suggests that speaking more than one language may delay different kinds of dementia - the loss of mental ability. In fact, researchers say speaking two languages appears to be more important than education in defending against dementias. A study in India examined the effect of knowing more than one language in delaying the first signs of several disorders. They includes Alzheiner's disease, frontotemporal dementia, vascular dementia, Lewy bodies dementia and mixed dementias.
Researchers studies nearly 650 people whose average age was 66. Two hundred forty of those studied suffered from Alzheimer's - the most common form of mental decline. Three-hundred-ninety-one of the subjects spoke two or more languages. Investigators found the dementias began about four-and-a half years later in those who spoke more than one language. Thomas Bak helped to organize the study. He is with the Center of cognitive Aging at the University of Edinburgh in Scotland. He believes the mental effort of seeking words in different languages improves what scientists call executive functioning or attention to tasks. This ability often weakness in people with dementias. Researchers found there was no extra gain in speaking more than two languages.
Thomas Bak says it does not appear important whether you learn a language at a young age or later in life. Scientists found that speaking more than one language helped delay dementia even in those who could not read. A report on bilingualism and dementias was published in the journal Neurology.