Scientists at the University of Birmingham have revealed that the brains of bilingual individuals have enhanced attentional control abilities. This gives them a superior ability to concentrate on specific task compared to their monolingual (those who only know one language) counterparts.
For the study, the team recruited 99 participants and made them participate in three well-known physiological tests that measure inhibitory control ability: the Flanker task, the Spatial Stroop task and the Simon task. 51 of the participants were English monolingual speakers, while 48 were highly proficient English-Chinese bilingual individuals who had learned English before the age of 10 and switch between both languages on a daily basis.
The team then measured the time participants took to respond to the stimuli presented in the tests on a computer screen.
In the Flanker task, researchers presented the participants with rows of arrows and asked them to indicate the direction of the central arrow by pressing a left or right button. This measure their ability to ignore the flanking arrows, which either pointed in the same or different direction as the central arrow.
In the Spatial Stroop task, the team asked the participants to indicate the direction of a single arrow, pointing either left or right, by pressing a button. Only one arrow was shown at a time, but it appeared either on the left or the right side of the screen. This was done to help or hinder their correct response, which in turn helped researchers test the participants’ focus.
The Simon task was very similar to the Spatial Stroop task. However, they used blue or red squares instead of arrows.
The team found that the participants in both groups were equally good at inhibiting interfering stimulus features in the bulk of their responses. However, monolingual individuals were very slow on responses in all tests compared to bilinguals. This means that bilingual speakers are better at sustaining attention than monolingual speakers, due to their lifetime experience in regularly having to switch between different languages.
“While there is plenty of evidence that there are cognitive benefits to being bilingual, there are also scholars that question the evidence due to replication failures,” explained Andrea Krott, one of the researchers who was involved in the study. “Our findings suggest that the way that data has been analysed might not have only led to the wrong conclusion that bilinguals have superior inhibition abilities, it might have also contributed to these replication failures.”
In the future, the team hopes to figure out how being bilingual shapes the brain of an individual to enhance their ability to maintain attention and focus.
“The next challenge is to determine how these behavioral changes are brought about by changes in the brain,” Krott said. “It is already well-known that the experience of speaking another language changes the structure of the brain and how it functions. But we do not understand very well how these changes lead to changes in behavior.”
Source: University of Birmingham
Reference: Bilingualism enhances attentional control in non-verbal conflict tasks – evidence from ex-Gaussian analyses* – Bilingualism: Language and Cognition