What Sentence Repetition Tasks Can Reveal about the Processing Effort Associated with Different Types of Code-Switching

Abstract

In this study, we explored the linguistic consolidation processes associated with bilingual processing using an experimental paradigm novel in bilingualism research, i.e., sentence repetition. We tested 46 L1-German L2-English bilinguals immersed in the L2 context. Firstly, we compared participants’ sentence repetition accuracy in single-language sentences and in sentences involving code-switches. Secondly, we investigated the processing cost associated with different types of code-switching, i.e., alternation, insertion, and dense code-switching. Finally, we assessed the following potential predictors of repetition accuracy: regular usage of different code-switching types, executive functions (working memory and inhibitory control), as well as relevant bilingualism variables (proficiency, dominance, and immersion). Our first finding was that bilinguals displayed reduced repetition accuracy in sentences involving code-switches compared to single-language sentences, but only when the single-language sentences were in the participants’ L1. This suggests that any processing costs associated with code-switching are modulated by bilinguals’ language background. Moreover, bilinguals’ poor performance in L2 compared to L1 single-language sentences, despite reporting high levels of L2 exposure frequency, highlights the importance of age of acquisition and dominance profiles for language processing. In terms of code-switching, our results revealed that bilinguals’ repetition accuracy differed across different types of code-switching. The processing effort associated with different types of code-switching in the sentence repetition task was primarily driven by the structural depth and the degree of mixing of the involved code-switch, i.e., dense forms of code-switching involving high levels of linguistic co-activation were harder to repeat than alternations involving unintegrated language switching. This effect partially converged with bilinguals’ sociolinguistic practices because bilinguals also reported lower exposure frequency to dense code-switching, but no direct correlations were observed at the level of individual differences. In terms of general cognitive functions, repetition accuracy was modulated by working memory but not by inhibitory control. By investigating this issue, we hope to contribute to our understanding of language processing in the face of cross-linguistic consolidation processes.