Being bilingual: not a cognitive advantage, according to new research

The Association for Psychological Science (APS) recently published the results research on bilingualism conducted by researchers at the University of Western Ontario. This study shows that bilingualism does not present significant cognitive advantages.

We will agree that being bilingual allows people many possibilities. Among other things, it is easier to find a job and to practice it. Speaking another language when traveling to other countries is also very useful. Socially, bilingual people can increase their interactions with others (friends, clients, colleagues, etc.). Being bilingual widens access to information, leisure and entertainment. 

It can also be assumed that bilingualism or plurilingualism offers cognitive advantages. Would the executive functions of bilingual people be more efficient? Would the cerebral bonds of young people with an attention disorder be more fluid when learning a second language? Could bilingualism have a cognitive protective effect as we age and delay or combat certain brain dysfunctions (dementia, for example)?

A team of researchers from University of Western Ontario looked into these assumptions. They noticed that previous studies on the link between bilingualism and cognitive functions showed different results. They often contradicted each other or their validity was called into question. Based sometimes on small samples, this research would have been biased by factors that influence the data, such as the socioeconomic situation, the geographical origin of the subjects and their education. They also found that studies supporting the theory of the benefits of bilingualism were more likely to be published as full papers than those that found the null hypothesis or the benefit to monolingual people, which calls into question the validity of these publications.

A study conducted with more than 11,000 volunteers

The Ontario team therefore conducted a new study, basing their research on 11,041 participants between the ages of 18 and 87. To succeed in getting that many participants, the study was done online. According to the researchers, the Internet offers a great opportunity to examine the relationship between bilingualism and executive functions in the general population. The wide range of participants presented a variety of socio-demographic factors necessary for the study (languages spoken, socioeconomic status, country of birth, education, etc.).

The analysis made it possible to compare a sample of subjects presenting similar (or paired) portraits, but separated into two subgroups, one being monolingual and the other bilingual. Another sample studied had more random factors for the two linguistic subgroups. The team was able to classify the subjects using the answers to the socio-demographic questions.

The participants then had to complete 12 cognitive tasks whose data was collected by the online platform. Cambridge Brain Sciences. These tasks were used to assess inhibition, executive functions, selective attention, reasoning, verbal short-term memory, spatial working memory, planning, cognitive flexibility. Each of these tasks was analyzed on the basis of three factors: reasoning, verbal skills and memory.

The invaluable help of technological tools for the analysis of large samples 

Thanks to the technological tools available today, the analysis of the results of a large sampling is possible. Calculating the results of the twelve tests by taking into account the three factors and the socio-demographic situations of each of the 11,041 participants is much too colossal work for five researchers. However, when the computer collects the data, pushes it into matrix calculations, and creates graphs for analysis, large-scale study becomes possible. Thus, the validity of the research is also more likely to eliminate errors. 

An observational study

It should be noted, however, that the study is said to be observational since the data was collected from volunteers who self-selected and were not randomly assigned to groups. The approach of this research was to examine the complex statistical relationship between performance on cognitive tasks and changes in brain activity in order to capture their mutual influences.

After analyzing the data, the group of researchers concludes that the results for the twelve cognitive tasks do not show significant differences between bilingual people and those who are monolingual. Wherever the results differ, the difference is very small, even for the age factor, and remains negligible. The null hypothesis of the cognitive advantage for bilingual people is therefore revealed by this study.

Despite the fact that being bilingual is not an advantage for brain function, the social and personal benefits of speaking two or more languages are, and always will be, considerable. 

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