Bilinguals Share Syntax Unsparingly

Abstract

Previous research suggests that bilinguals share syntactic processes and representations for constructions similar in two languages (actives/passives). However, languages often use different constructions to convey the same meaning. For example, the meaning of a causative construction in English (Jen had her computer fixed) is conveyed using an active transitive construction in Korean (Jen-NOM her computer-ACC fixed). Yet, little is known about how bilinguals represent and process such constructions. The present study aims to address the issue by investigating how Korean-English bilinguals represent cross-linguistically different constructions (causatives) in comparison to cross-linguistically similar constructions (transitives). There are, broadly speaking, two accounts of bilingual syntactic processing: the shared-syntax account and the separate-syntax account. The shared-syntax account suggests that (1) bilinguals share syntactic representations between languages and (2) the grammatical rules of one language influence syntactic processing in the other (e.g. Hartsuiker et al., 2004). In contrast, the separate-syntax account (e.g. De Bot, 1992) suggests that bilinguals store and access syntactic information separately for two languages. We evaluate these two accounts. Experiment 1 investigates how Korean-English bilinguals represent transitive structures using between-language structural priming. If syntactic processes and representations become shared for transitives in L1 and L2 as a function of proficiency (shared-syntax account), proficient Korean-English bilinguals should show a stronger between-language priming effect than less proficient bilinguals. By contrast, if syntactic representations are separate in L1 and L2 (separate-syntax account), we do not expect any priming between Korean and English. Consistent with previous research, our results showed that proficient Korean-English bilinguals exhibited a stronger priming effect than less proficient bilinguals, providing support for the shared-syntax account. Experiment 2 investigates how Korean-English bilinguals represent causative constructions that are different in the two languages. We paired a causative event (Jen having her computer fixed) either with an active transitive (Jen fixed her computer) or a causative sentence in English (Jen had her computer fixed), and asked participants to decide whether the given sentence matches the depicted event (picture-sentence verification task). If syntax is shared between L1 and L2 (shared-syntax account), a causative event should activate both causative (via its link in English) and active structures (via its link in Korean). Crucially, as transitive structures become shared between Korean and English (Exp1), the shared-syntax account predicts that a strong link between a causative event and an active structure in Korean should increasingly cause Korean-English bilinguals to mistake an active construction for an appropriate description of a causative event in English. However, if bilinguals develop distinct syntactic representations for causatives (separate-syntax account), Korean-English bilinguals should be more likely to reject than accept an active structure as a correct English description of a causative event. Our results showed that proficient bilinguals were indeed more likely to accept an active structure (as well as a causative) as an appropriate description of a causative event than less proficient bilinguals, providing support for the shared-syntax account. Taken together, our results suggest that bilinguals share syntactic processes and representations for both similar and different constructions, indicating that the bilingual system is highly integrated.