What Cognates Reveal about Default Language Selection in Bilingual Sentence Production

The Effect of Syntactic Similarity on Intra-Sentential Switching Costs: Evidence from Chinese-English Bilinguals

In order to better understand the role of syntactic similarity in a code-switched sentence, the current study explored the effect of similar and different syntactic structures on Chinese-English bilinguals' intra-sentential switching costs. L2 proficiency and switching directions as factors that potentially intervene in bilingual performance were together explored to see if there was any interaction. We manipulated the degree of syntactic similarity by utilizing clauses in active voice (greater similarity) and passive voice (lesser similarity). The study conducted a self-paced reading paradigm as a more natural language reading processing. Results showed overall longer reading times for active sentences than passive counterparts, which supported a syntactic similarity impediment rather than facilitation. The impediment seemed to be predominant irrespective of L2 proficiency. Furthermore, syntactic similarity modulated the asymmetry of switching costs between forward (L1-L2) and backward (L2-L1) direction: word RTs for the 1st and the 2nd switched word yielded greater costs in L2-L1 condition, while greater costs in L1-L2 condition was observed in 3rd switched word RTs and average RTs. The present study observed syntactic similarity impediment rather than facilitation for Chinese-English bilinguals. Notably, syntactic similarity plays a predominant role compared to L2 proficiency, and modulates the asymmetry between switching directions.

A Blessing in Disguise: Flanking Words Can Cancel Language Switch Costs

Prior research has shown that a sentence context can decrease the necessity for language control relative to single word processing. In particular, measures of language control such as language switch costs are reduced or even absent in a sentence context. Yet, this evidence is mainly based on bilingual language production and is far from straightforward. To further investigate this issue in the comprehension modality, we relied on the lexical flanker task, which is known to introduce sentence-like processing. More specifically, Dutch-English bilinguals (n = 68) performed a classification task in mixed language blocks on target words that were either presented alone or flanked by unrelated words in the same language. While overall no L1 switch costs were observed, we only observed L2 switch costs in the no-flanker condition. This pattern of results indicates that the presence of flankers can reduce or even abolish switch costs, suggesting that the language control process can benefit from sentence(-like) processing compared to single word processing.

Different language control mechanisms in comprehension and production: Evidence from paragraph reading

Chinese-English bilinguals read paragraphs with language switches using a rapid serial visual presentation paradigm silently while ERPs were measured (Experiment 1) or read them aloud (Experiment 2). Each paragraph was written in either Chinese or English with several function or content words switched to the other language. In Experiment 1, language switches elicited an early, long-lasting positivity when switching from the dominant language to the nondominant language, but when switching to the dominant language, the positivity started later, and was never larger than when switching to the nondominant language. In addition, switch effects on function words were not significantly larger than those on content words in any analyses. In Experiment 2, participants produced more cross-language intrusion errors when switching to the dominant than to the nondominant language, and more errors on function than content words. These results implicate different control mechanisms in bilingual language selection across comprehension and production.

The effect of inhibitory control and language proficiency on intra-sentential switching costs in reading comprehension

Based on the inhibition account and activation account, inhibitory control and language proficiency play big roles on language control mechanisms underlying language switching respectively. But it is still debatable whether inhibitory control and language proficiency play roles in sentential context during bilingual language comprehension, and how and when they work if they both do. The present study examined the specific roles of language proficiency and inhibitory control on modulating intra-sentential switching costs in Chinese-English bilinguals using self-paced reading task. Results indicated that language proficiency and switching direction modulated intra-sentential switching costs significantly. Switching costs were larger when switching into L1 than into L2 for the first two code-switched words due to inhibitory effect, but more costly switching into L2 than into L1 since the third code-switched words owing to the effect of relative language proficiency. During bilingual language processing, inhibition and activation of languages shaped a dynamic interplay of complementary language control processes. Specifically, inhibitory control and language proficiency work as a dynamic continuum in language switching at sentence level. Switching into L1 requires the release of inhibition to L1, but switching into L2 asks the activation and access of L2. The interaction effects of language proficiency and inhibitory control influenced the exertion and components of inhibition. This study reconciled the independent roles of language proficiency and inhibitory control on language switching and constructed a new continuum based on language proficiency.

Inhibitory control of the dominant language: Reversed language dominance is the tip of the iceberg

Theories of speech production have proposed that in contexts where multiple languages are produced, bilinguals inhibit the dominant language with the goal of making both languages equally accessible. This process often overshoots this goal, leading to a surprising pattern: better performance in the nondominant vs. dominant language, or reversed language dominance effects. However, the reliability of this effect in single word production studies with cued language switches has been challenged by a recent meta-analysis. Correcting for errors in this analysis, we find that dominance effects are reliably reduced and reversed during language mixing. Reversed dominance has also consistently been reported in the production of connected speech elicited by reading aloud of mixed language paragraphs. When switching, bilinguals produced translation-equivalent intrusion errors (e.g., saying pero instead of but) more often when intending to produce words in the dominant language. We show this dominant language vulnerability is not exclusive to switching out of the nondominant language and extends to non-switch words, linking connected speech results to patterns first reported in single word studies. Reversed language dominance is a robust phenomenon that reflects the tip of the iceberg of inhibitory control of the dominant language in bilingual language production.

Testing the Triggering Hypothesis: Effect of Cognate Status on Code-Switching and Disfluencies

"Triggered switching" is the theory that code-switching happens more often with words connected to both languages, such as cognates. Corpus analyses have supported this theory; however, they do not allow testing for directional causality. Here, we test the triggering hypothesis through a picture-naming task, and examine whether cognates trigger code-switches, as well as more subtle interference effects resulting in disfluencies. Forty English-Spanish bilinguals completed a picture-cued sentence production task in three conditions: English-only, Spanish-only, and mixed. Half of the pictures represented Spanish-English cognates. Unsurprisingly, participants were more likely to code-switch when asked to use both their languages compared to only their dominant or non-dominant language. However, participants were not more likely to switch languages for cognate than for non-cognate trials. Participants tended to be more fluent on cognate trials in the dominant and the non-dominant condition, and on non-cognate trials in the mixed-language condition, although these effects were not significant. These findings suggest that both language context and cognate status are important to consider when testing both overt switches and disfluencies in bilingual speech production.

How does bilingual experience influence novel word learning? Evidence from comparing L1-L3 and L2-L3 cognate status

Bilingual experience exerts a complex influence on novel word learning, including the direct effects of transferable prior knowledge and learning skill. However, the facilitation and interference mechanism of such influence has largely been tangled by the similarity of the previously learned word knowledge. The present study compared Chinese-English bilinguals' paired-associate learning of nonwords in logographic and alphabetic writing systems. The logographic nonwords resemble the form and meaning of L1 Chinese words in varying degrees, being cognates, false cognates, or non-cognates of Chinese. The alphabetic nonwords resemble the form and meaning of L2 English words, being cognates, false cognates, or non-cognates of English. The learning sequence of logographic and alphabetic words was cross-balanced. The learning results were measured in production and recognition tasks. As for learning the logographic nonwords, both the recognition and production results showed that cognates were learned significantly faster than the non-cognates, and the false cognates were also learned significantly faster than the non-cognates. This suggests stronger facilitation rather than interference from L1 on novel word learning. As for learning the alphabetic nonwords, both the recognition and production results revealed that cognates were learned significantly faster than the non-cognates, but false cognates showed no advantage over the non-cognates. This indicates that interference from L2 is stronger than that from L1. Taken together, the results provide new evidence for the dissociable facilitation and interference effects of bilingual experience. These results carry potential educational implications in that learning novel words depends on substantial bilingual experience.

Language-switch Costs from Comprehension to Production Might Just Be Task-switch Costs

Spanish-English bilinguals switched between naming pictures in one language and either reading-aloud or semantically classifying written words in both languages. When switching between reading-aloud and picture-naming, bilinguals exhibited no language switch costs in picture naming even though they produced overt language switches in speech. However, when switching between semantic classification and picture naming, bilinguals, especially unbalanced bilinguals, exhibited switch costs in the dominant language and switch facilitation in the nondominant language even though they never switched languages overtly. These results reveal language switching across comprehension and production can be cost-free when the intention remains the same. Assuming switch costs at least partially reflect inhibition of the nontarget language, this implies such language control mechanisms are recruited only under demanding task conditions, especially for unbalanced bilinguals. These results provide striking demonstration of adaptive control mechanisms and call into question previous claims that language switch costs necessarily transfer from comprehension to production.