Learning a second language in childhood is inherently advantageous for communication. However, parents, educators and scientists have been interested in determining whether there are additional cognitive advantages. One of the most exciting yet controversial findings about bilinguals is a reported advantage for executive function. That is, several studies suggest that bilinguals perform better than monolinguals on tasks assessing cognitive abilities that are central to the voluntary control of thoughts and behaviours—the so-called ‘executive functions’ (for example, attention, inhibitory control, task switching and resolving conflict).

Although a number of small and large-sample studies have reported a bilingual executive function advantage, there have been several failures to replicate these findings and recent meta-analyses have called into question the reliability of the original empirical claims. In the latest, larger study of more than 4,500 students of 9- to 10-year-olds across the United States, there is little evidence for a bilingual advantage for inhibitory control, attention and task switching, or cognitive flexibility, which are key aspects of executive function.

In summary, notwithstanding the inherently positive benefits of learning a second language in childhood, for the moment scientist have found little evidence that it engenders additional benefits to executive function development.

More on the latest study here