Over the past few years, studies have been saying that bilinguals have a benefit over people who speak only one language. Well, aside from the obvious reason of being able to communicate better when traveling in a foreign country, these studies have stated that people who speak more than one language, or polyglots, have better executive functioning skills. These are skills or abilities that pertain to planning, switching between different tasks, and filtering distractions in order to accomplish a goal.
However, in a recent study conducted in the United States, it was reported in Nature Human Behavior that the number of languages that a person knows how to speak does not equal their strength in executive functioning. The study was called the ABCD Study and it involved 4524 children aged 9 to 10, who answered surveys from twenty-one research sites across the country. Among these kids, 1740 children spoke English and a second language. Each child took three tests, which measured their ability to avoid distractions and to switch between tasks. After the tests, the researchers found that there was no difference in the performance between the children who spoke only English and the children who spoke more than one language. "We really looked," said study co-author Anthony Dick, who is also a developmental cognitive neuroscientist at Florida International University. "We didn't find anything."
The difference in results only showed in the part of the survey where their English vocabulary was tested. Bilingual children seemed to have slightly lower scores than the children who spoke just English. However, Dick describes this as "a drop in the bucket." This is while taking note that his son has been attending a Spanish-English school for years.
Dick stresses that the study was only aimed to narrow down the question of whether being bilingual strengthens one's executive functioning skills or not. "I don't want this to be a paper about how parents should not have their children learn a second language," Dick says, "there are inherent benefits outside of executive function to learning a second language - huge benefits."
Social scientist from McGill University, Gigi Luk has noted that the science behind polyglotism is too complex to draw conclusions from a survey such as the ABCD Study, without taking into consideration the daily activities of the children, and how and when they were taught the second language. "We just don't have enough information about the bilingual experience that these children have every day," says Luk.
With this being said, more studies are required before we can draw any conclusions on the effects of being bilingual on the brain and its executive function.