Explaining Individual Differences in Executive Functions Performance in Multilinguals: The Impact of Code-Switching and Alternating Between Multicultural Identity Styles

Abstract

This study sheds new light on the relative impact of switching between languages and switching between cultures on Executive Functions (EFs) in bilinguals. Several studies have suggested that bilingualism has a measurable impact on executive functioning, presumably due to bilinguals' constant practice in dealing with two languages, or two cultures. Yet, the evidence on the relative contribution of culture and bilingualism to EFs is not well understood, because disentangling language, culture and immigration status is very difficult. The novelty of our approach was to keep the language pair and immigration status constant, whilst the cultural identity of participants was systematically varied, and measured at the individual level (not just at group level). Two groups of Turkish-English bilinguals, all adult immigrants to the United Kingdom, took part in the study, but one group (n = 29) originated from mainland Turkey and the other (n = 28) from Cyprus. We found that the bilinguals experienced smaller Conflict Effects on a Flanker task measuring inhibition, by comparison with monolingual British participants (n = 30). The key variable explaining EF performance variance at the individual level turned out to be bilinguals' Multicultural Identity Style. In particular those who indicated that they attempted to alternate between different British and Turkish (Cypriot) identity styles were found to have shorter RTs on incongruent trials of the Flanker task. The two multicultural identity variables, Alternating and Hybrid Identity Styles, together explained 32% in RTs over and above Education, Working Memory and Nonverbal reasoning (overall explained variance 49%). Thus, the data provide strong evidence for the impact of culture on EFs. We suggest that, as a result of their daily practice in recognizing cultural cues which highlight the need to switch to a different cultural frame, multicultural bilinguals develop a heightened context-sensitivity, and this gives them an advantage over monolinguals in a Flankers task. Our approach, which draws on models from cross-cultural psychology, bilingualism and executive functioning, illustrates the importance of theory building in which sociolinguistic and cultural variables are integrated into models of EFs.

Code-Switching patterns differentially shape cognitive control: Testing the predictions of the adaptive control hypothesis

“…Further, previous studies have treated three code-switching patterns as separate variables despite demonstrating similar correlations (.41 to .68; Lai & O'Brien, 2020). Results from frequency judgment tasks that assessed alternation, insertion, and congruent lexicalization also generally show that bilingual participants engage in all three patterns (Hofweber et al, 2016; Hofweber, Marinis & Treffers-Daller, 2020a; Treffers-Daller, Ongun, Hofweber & Korenar, 2020). Therefore, we believe that the decision to treat these code-switching patterns as separate variables is reasonable.…”

Neural Processing Underlying Executive Functions in Bilinguals: “Heads I Win, Tails You Lose”

“…Sociolinguistic practices could also influence which executive processes are enhanced by bilingualism (Hofweber et al, 2020 ). Differences between cultures may constitute another source of differences in executive functioning (Samuel et al, 2018 ; Treffers-Daller et al, 2020 ). Overall, the samples recruited for studies have differed widely in terms of the variables listed above (Cespón and Carreiras, 2020 ), possibly explaining a substantial portion of the variability in results.…”

Structural neural correlates of habitual code-switching practices in bilinguals

“…Besides directionality, another factor by which code-switching may engage cognitive control processes to various degrees is the level of separation between the two languages within a switch (Green & Wei, 2014;Hofweber et al, 2016Hofweber et al, , 2020bTreffers-Daller et al, 2020). The primary distinction is whether a switch occurs within one sentence which features lexical units and grammatical elements from both languages (intrasentential code-switching) (Treffers-Daller, 1991) or after a sentence has been completed (intersentential codeswitching) (Appel & Muysken, 2005).…”

“…Thus, not only switching between sentences, but also highly separated forms of intrasentential codeswitching can be linked to structural adaptions in the thalamus. Alternation has also been previously linked to reactive inhibitory control processes (Hofweber et al, 2020), but it has remained unclear whether the inhibitory control demands are so high that they should have structural consequences in the brain. Our findings suggest that alternation indeed poses inhibitory control demands that would require structural adaptations in the thalamus, the subcortical hub of inhibitory control, to subserve these processes effectively.…”