Carissa Kang (Cornell University), Gita Martohardjono (City University of New York), & Barbara Lust (Cornell University)
Code-switching; Bilinguals; Executive FunctionIn this study, we examine the link between code-switching (CS; alternating between two or more languages within a conversation) – and executive function (EF). Past work revealed that language switching is challenging and requires cognitive control, and similar brain regions are activated during language switching and EF tasks (Abutalebi & Green, 2007). Others have speculated that CS may enhance cognitive advantages attributed to bilingualism. Although there has been some work suggesting that more frequent language switching correlates with better EF task performance (Soveri, Rodriguez-Fornells, & Laine, 2011; Yim & Bialystok, 2012), to date there has been no evidence that within subjects, CS and EF interact directly.
This raises the prediction that mechanisms of EF and CS in bilingualism would interact, leading to behavioral effects. In fact, a reciprocal interaction might be possible. This prediction is tested here with a new paradigm to assess direct interaction between EF and CS, to see if depletion of EF will lead to a diminishment of CS productivity. Furthermore, given that the nature of bilingualism varies so widely, we test whether this hypothesized effect would correlate with participants’ self-reported frequency of mixing, attitudes towards CS, and level of bilingualism.
To measure CS, participants discussed topics and switched languages upon hearing a beep. CS performance was quantified by several measures including the reaction time (RT) taken to switch into another language after the beep. Participants completed two CS tasks – one at the start (CS1) and one after EF depletion (CS2). We used the Stroop (in both languages; all incongruent trials) and a verbal task switching (Yim & Bialystok, 2012; see Appendix) to deplete participants’ verbal EF.
Initial data analyses included 17 Chinese-English bilinguals (8 females, M = 21.4 (SD = 1.3)) varying in nature of bilingualism (Table 1). Correlational analyses revealed that RT difference (i.e., whether participants took longer time to switch in CS2) was negatively correlated with: a) attitudes towards CS, b) frequency of mixing, and c) verbal task switching scores (Table 2). Level of bilingualism was not significantly correlated with RT difference. Linear regression revealed that only frequency of mixing marginally predicted RT difference (R2= .21, SE = .46, p = .068). This suggests that those with positive attitudes towards mixing languages who frequently mixed languages were less likely to be negatively affected by the verbal EF depletion, as seen by their CS2 performance. Our results have implications for a general theory involving the representation of general cognitive processes such as EF and linguistic mechanisms of control.
 Abutalebi, J. & Green, D. Bilingual language production: The neurocognition of language representation and control. Journal of Neurolinguistics, 20:242-275, 2007.
 Soveri, A., Rodriguez-Fornells, A., Laine, M. Is there a relationship between language switching and executive functions in bilingualism? Introducing a within group analysis approach. Frontiers in Psychology, 2:1-8, 2011.
 Yim, O., & Bialystok, E., (2012). Degree of conversational code-switching enhances verbal task switching in Cantonese-English bilinguals. Bilingualism: Language and Cognition, 15:873 -883, 2012.