For decades, the cognitive advantages—and disadvantages—of learning a second language have been widely disputed. While multiple studies have found that the bilingual-advantage exists, others have reported the opposite, concluding that there was no significant difference in cognitive function between monolinguals and bilinguals (Poarch and Krott 2019). These inconsistent findings have prompted a recent surge in meta-analysis studies, where results from independent studies are synthesized to form a conclusion about our current understanding of multilingualism and cognitive ability.
Historically, there have been a number of psychological experiments researchers have gravitated towards when quantifying the cognitive functioning abilities of target groups. Studies investigating the link between multilingualism and executive function (the mental processes that control our behavior), for instance, have commonly involved popular psychological tests such as the Flanker, Simon, and Stroop tasks, in addition to switching tasks and the attention network test (van den Noort et al. 2019). These psychological experiments help researchers measure an individual’s cognitive response to various stimuli (Poarch and Krott 2019).
Combining the results obtained from studies involving these tasks, Dr. van den Noort and colleagues published a meta-analysis review of the bilingual advantage in 2019. After using several eligibility criteria to select 56 studies for their meta-analysis, the research team found that 54.3% of the selected studies supported a bilingual advantage in executive function, whereas 28.3% reported mixed results and 17.4% obtained results that challenged it. Interestingly, the results of the individual studies seemed to be influenced by several factors, including the type of experiment used and the year of publication.
For example, studies using the Stroop, Flanker, and attention network tasks favored the bilingual advantage, while studies using the Simon and switching tasks tended to report mixed results. The team also found that a significantly higher percentage of studies conducted between 2004-2012 supported a bilingual advantage, whereas more studies conducted between 2013-2018 presented mixed findings or challenged it. This suggested to the researchers that publication bias skewed towards the bilingual advantage might have been stronger in the previous decade.
While evidence supporting the bilingual advantage was found to be more abundant, the results of the meta-analysis could not definitively conclude that a cognitive advantage exists. The researchers therefore proposed that better methodologies and more large-scale longitudinal studies are needed to help advance the field (van den Noort 2019). Many other meta-analysis studies agree with these results. Researchers of a review published two years later did not find coherent evidence supporting a cognitive functioning advantage in bilinguals. The research team also suggested that future studies should adopt more refined experimental methodology standards and be done on larger group sizes to reach a more conclusive result (Lowe et al. 2021).
Since the bilingual advantage theory has neither been confirmed nor disproven as of yet, the need for further research that is both better in design and more comprehensive is apparent. Enhancing our understanding of bilingualism’s cognitive effects through further research will prove to be useful for a number of populations, including parents, teachers, and psychologists.
“Flanker Task - a 5 Minute Guide from Theory to Implementation.” Testable - Create Experiments | Recruit Participants, 14 Sept. 2021, www.testable.org/experiment-guides/executive-function/flanker-task.
Harvard University. “Executive Function & Self-Regulation.” Center on the Developing Child at Harvard University, Harvard University, 2015, developingchild.harvard.edu/science/key-concepts/executive-function/.
Lowe, Cassandra J., et al. “The Bilingual Advantage in Children’s Executive Functioning Is Not Related to Language Status: A Meta-Analytic Review.” Psychological Science, vol. 32, no. 7, July 2021, pp. 1115–1146, 10.1177/0956797621993108.
Poarch, Gregory J., and Andrea Krott. “A Bilingual Advantage? An Appeal for a Change in Perspective and Recommendations for Future Research.” Behavioral Sciences, vol. 9, no. 9, 4 Sept. 2019, p. 95, www.mdpi.com/2076-328X/9/9/95/htm, 10.3390/bs9090095. Accessed 30 Nov. 2019.
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“Simon Task.” Science of Behavior Change, scienceofbehaviorchange.org/measures/simon-task/#:~:text=The%20Simon%20Task%20is%20a.
“Stroop Task.” Psytoolkit.org, 2018, www.psytoolkit.org/experiment-library/stroop.html.
van den Noort, Maurits, et al. “Does the Bilingual Advantage in Cognitive Control Exist and If So, What Are Its Modulating Factors? A Systematic Review.” Behavioral Sciences, vol. 9, no. 3, 13 Mar. 2019, p. 27, www.ncbi.nlm.nih.gov/pmc/articles/PMC6466577/, 10.3390/bs9030027.