The Complex Nature of Bilinguals' Language Usage Modulates Task-Switching Outcomes.

Hwajin Yang,Sujin Yang,Andree Hartanto

doi:10.3389/fpsyg.2016.00560

Abstract

In view of inconsistent findings regarding bilingual advantages in executive functions (EF), we reviewed the literature to determine whether bilinguals' different language usage causes measureable changes in the shifting aspects of EF. By drawing on the theoretical framework of the adaptive control hypothesis—which postulates a critical link between bilinguals' varying demands on language control and adaptive cognitive control (Green and Abutalebi, 2013), we examined three factors that characterize bilinguals' language-switching experience: (a) the interactional context of conversational exchanges, (b) frequency of language switching, and (c) typology of code-switching. We also examined whether methodological variations in previous task-switching studies modulate task-specific demands on control processing and lead to inconsistencies in the literature. Our review demonstrates that not only methodological rigor but also a more finely grained, theory-based approach will be required to understand the cognitive consequences of bilinguals' varied linguistic practices in shifting EF.

Highlights

Executive functions (EF) refer to a multifaceted construct of a general control process that consists of three postulated functions: inhibition, updating, and shifting (Miyake et al, 2000)
We examined three aspects of bilinguals’ language-switching experiences: (a) the interactional context of conversational exchanges, (b) language-switching frequency, and (c) typology of code-switching, which refers to the alternation between two or more languages
Prior and Gollan (2011) first examined this issue by comparing monolinguals to SpanishEnglish and Mandarin-English bilinguals who differed in their self-reported frequency of language switching. They found that only Spanish-English bilinguals—who were regarded as frequent language switchers—had smaller switch costs than monolinguals, suggesting that there may be a minimum threshold for language-switching frequency that confers advantages on task switching

Summary

INTRODUCTION

Executive functions (EF) refer to a multifaceted construct of a general control process that consists of three postulated functions: inhibition, updating, and shifting (Miyake et al, 2000). Verhagen et al (2015) reported that bilingual children whose parents spoke different languages performed significantly better on the Stroop and delay-of-gratification tasks than bilinguals whose parents spoke the same language as the child It is clear, that the interactional context of bilinguals’ conversational exchanges is a critical factor that renders bilingual experience more advantageous in shifting EF and, in turn, enhances task-switching performance. Prior and Gollan (2011) first examined this issue by comparing monolinguals to SpanishEnglish and Mandarin-English bilinguals who differed in their self-reported frequency of language switching Not surprisingly, they found that only Spanish-English bilinguals—who were regarded as frequent language switchers—had smaller switch costs than monolinguals, suggesting that there may be a minimum threshold for language-switching frequency that confers advantages on task switching. More frequent intersentential codeswitching likely facilitates bilingual advantages in task switching In support of this view, recent studies suggest that the demands of language control modulate task-switching performance. The typology of code-switching is an important factor that sheds light on the demands of various bilingual experiences and their impact on task-switching performance

Participants

Findings

CONCLUSIONS