Neuroscience researchers are increasingly coming to a consensus that bilingualism has many positive consequences for the brain, wrote the Los Angeles Times Feb. 26, in story that also appeared in the Chicago Tribune and on numerous US television news websites. Several such researchers travelled to this month’s annual meeting of the American Association for the Advancement of Science in Washington, DC, to present their findings, wrote the Times:

These benefits come from having a brain that’s constantly juggling two – or even more – languages, said Ellen Bialystok, [Distinguished Research Professor in Psychology, Faculty of Health] at York University in Toronto, who spoke at the AAAS annual meeting. For instance, a person who speaks both Hindi and Tamil can’t turn Tamil off even if he’s speaking to only Hindi users, because the brain is constantly deciding which language is most appropriate for a given situation.

This constant back-and-forth between two linguistic systems means frequent exercise for the brain’s so-called executive control functions, located mainly in the prefrontal cortex. This is the part of the brain tasked with focusing one’s attention, ignoring distractions, holding multiple pieces of information in mind when trying to solve a problem, and then flipping back and forth between them.

“If you walk into a room, there are a million things that could attract your attention,” Bialystok said. “How is it we manage to focus at all? How does our mind pay attention to what we need to pay attention to without getting distracted?”

To test one’s ability to identify pertinent nuggets while being bombarded with extraneous information, scientists use something called the Stroop test. Subjects are presented with a word for a particular colour and asked to identify the colour of ink it’s printed in. So if the word is “blue” and it’s printed in blue, no problem. If, on the other hand, the word “blue” is printed in red, they have to sort out which piece of information – the colour of the ink, or the colour being spelled out – is the one they need.

“This is extremely hard to do, because it’s terribly difficult to block out the information from the word,” Bialystok said.

In monolingual speakers, this kind of mental curveball will add 240 milliseconds to their reaction time – a significant delay, in brain reaction terms. Bilingual people, on the other hand, take just 160 extra milliseconds to sort this out. Bialystok theorizes that it’s because they’re used to prioritizing information in potentially confusing situations all day.alz

Those advantages aren’t just useful for schoolchildren – they last over the course of a lifetime. A study published last year in the journal Neurology surveyed 211 patients diagnosed with Alzheimer’s and found that those who spoke only one language saw the onset of their first symptoms four to five years earlier than their bilingual peers. While knowing two languages doesn’t fight the disease, it does strengthen those parts of the brain that are susceptible to dementia’s early attacks, allowing them to withstand the assault much longer.

Republished courtesy of YFile – York University’s daily e-bulletin.