A study of cognitive abilities in bilingual children: Advantages and disadvantages

Several research studies have found controversial findings in some cognitive tasks (e.g., memory, executive function, problem solving) for bilinguals. Some researchers argue for bilingual advantage, whereas others argue for bilingual disadvantage. The purpose of this project was to investigate the dissociative effects of a variety of cognitive tasks in bilingual children.

Two separate studies were carried out to reveal these dissociative effects of bilingualism or bilingual advantages/disadvantages. We discussed our findings on the basis of the different nature of cognitive tasks, since each cognitive task demands involving a certain cognitive domain. In our first database, we’ve used a reading task as a more complex cognitive task. In the second database, we have explored further the cognitive performance of bilingual children comparing their monolingual peers in various cognitive tasks from low to high levels of function. Our goal was to provide a bilingual profile of cognitive dissociations for children.  Our two main questions from two databases were: whether reading itself is a dissociative cognitive task for bilingual children or not and whether bilingualism would have some effect on increasing/decreasing reading difficulties.

It is noteworthy that the data regarding the first database has been collected from Iran as a multicultural country.  It includes 1614 primary school children (7-12 years old) in 3 cities of Iran (582 primary school children from Tehran as one monolingual group, 513 children from Tabriz, 519 children from Sanandajas two bilingual groups). We studied and compared their performance in four reading tasks(lexical and non-lexical reading tasks). In the second database, the performance of Iranian-Swedish bilingual children with/without reading problems (50 in each group) on various cognitive tasks were studied and compared with their Swedish monolingual peers with/without reading problems (50 in each group). The cognitive tasks used in these studies not only include reading tasks but also contain different cognitive domains such as executive functions (i.e., attention, inhibitory control & problem solving), working memory, episodic and semantic memory. The results of this project were both theoretically and practically important.

Theoretically, we found a good answer for the argument between two groups of researchers in the debate between bilingual advantage and disadvantage. We argue for both bilingual advantage and disadvantage depending on the nature of the task. Practically, parents and teachers can use the results of this project for educational purposes.

An article is published in the Scandinavian Journal of Psychology.