Characterizing Bilingual Effects on Cognition: The Search for Meaningful Individual Differences

Abstract

A debate over the past decade has focused on the so-called bilingual advantage—the idea that bilingual and multilingual individuals have enhanced domain-general executive functions, relative to monolinguals, due to competition-induced monitoring of both processing and representation from the task-irrelevant language(s). In this commentary, we consider a recent study by Pot, Keijzer, and de Bot (2018), which focused on the relationship between individual differences in language usage and performance on an executive function task among multilingual older adults. We discuss their approach and findings in light of a more general movement towards embracing complexity in this domain of research, including individuals’ sociocultural context and position in the lifespan. The field increasingly considers interactions between bilingualism/multilingualism and cognition, employing measures of language use well beyond the early dichotomous perspectives on language background. Moreover, new measures of bilingualism and analytical approaches are helping researchers interrogate the complexities of specific processing issues. Indeed, our review of the bilingualism/multilingualism literature confirms the increased appreciation researchers have for the range of factors—beyond whether someone speaks one, two, or more languages—that impact specific cognitive processes. Here, we highlight some of the most salient of these, and incorporate suggestions for a way forward that likewise encompasses neural perspectives on the topic.

Bilingualism caught in a net: A new approach to understanding the complexity of bilingual experience.

“…Consequently, this work has considerable potential to unravel the basic properties of the bilingualism phenomenon and substantially contribute to the way it should be conceptualized in the literature. On a methodological level, the research will show whether or not the current quests for a bilingualism quotient (Marian & Hayakawa, 2021; see also Backer & Bortfeld, 2021; Beatty-Martínez & Titone, 2021; Navarro-Torres et al, 2021) are likely to be successful. The superiority of the hierarchical factor model over the network model would indicate the possibility of extracting a single quantifiable index of bilingualism.…”

Attending multiple languages: the relation between individual multilingual language use and attentional control

“…The recent suggestion that a potential multilingual advantage lies in attentional systems [5,6] is accompanied by the recognition of the importance of considering individual differences in multilingual experiences [10,12]. It follows that a study of a varied range of individual multilingual experience factors in relation to attentional control can lead to important insights as to the nature of any multilingual cognitive advantage.…”

“…Inconsistencies in findings could, for example, be explained by variability in study samples, where factors that vary between individuals are not taken into account. The current debate has therefore in turn sparked a reevaluation of the definition of multilingualism [9][10][11][12][ [9][10][11][12] and more research is conducted detailing the diversity of multilingual experiences and backgrounds (cf. [8] [8]).…”

Does Early Exposure to Chinese–English Biliteracy Enhance Cognitive Skills?

“…This bilingual cognitive advantage lies in neuroplasticity, which refers to the ways in which the brain’s abilities to adapt in response to new experiences change throughout a person’s lifetime ( Gunnerud et al, 2020 ). This early advantage has been attributed to bilinguals’ enhanced cognitive control mechanism, which allows them to focus their attention on specific tasks without becoming distracted or retraining habitual behavior ( Backer and Bortfeld, 2021 ).…”