Are inconsistent bilingual-monolingual cognitive differences the result of population miscategorization?

Decades of psycholinguistic research have attempted to determine whether a “bilingualadvantage” exists for cognitive abilities (e.g., Bialystok & Craik, 2010; Cummins, 1977; for a metaanalysis,see Grundy & Timmer, 2017). More recent work has shifted away from investigating thebroader matter of cognition and working memory to focus on specific domains within those capacities(e.g., Linck et al., 2014). Despite countless studies, however, the existence of thisphenomenon remains unconfirmed. This paper examines evidence for and against the presence of a“bilingual advantage” in multiple tasks of working memory and cognitive control, reviewing studies thatcompare monolingual and bilingual performance. It further looks at populations that are understudied inrelation to these questions (i.e., L2 learners and heritage speakers). Finally, the topic of L2 attrition isdiscussed, alongside a novel perspective that may explain the inconsistencies in bilingual-monolingualcomparisons of performance on cognitive tasks.