Language control is not a one-size-fits-all languages process: evidence from simultaneous interpretation students and the n-2 repetition cost

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.

The effects of executive functions on language control during Chinese-English emotional word code-switching

Executive functions (EFs) have great impact on language control indexed by language switch costs during production-based language switching. Yet, how they influence language control during comprehension-based language switching between embodied first language (L1, Chinese) emotional words and less embodied second language (L2, English) emotional words is less understood. Employing an emotional priming paradigm, this study recruited Chinese-English bilinguals as participants, and used emotional faces and words as experimental materials to explore the effects of cool [i.e., inhibitory control ability, IC ability] and hot (i.e., emotional valence and emotional congruency) EFs on language switch costs (i.e., language control) during Chinese-English emotional word comprehension. The results showed larger language switch costs in the emotional congruent condition relative to emotional conflict condition, larger Chinese switch costs than English switch costs, and larger language switch costs for negative over positive emotional words in the emotional congruent condition. In addition, high-IC participants showed larger English switch costs for negative emotional words compared with low-IC participants. These results indicated that hot EF and the embodiment of language had an impact on both language control and the modulation of cool EF on language control, and that the components of hot EFs interacted and jointly affected language control during language switching.

When Language Switching is Cost-Free: The Effect of Preparation Time

Previous research has shown that language switching is costly, and that these costs are likely to persist even when speakers are given ample time to prepare. The aim of this study was to determine whether there are cognitive limitations to speakers' ability to prepare for a switch, or whether a new language can be prepared in advance and any cost to switch language eliminated. To explore this, language switching costs were measured in a group of Dutch-English (L1-L2) bilinguals who named pictures in their two languages while the preparation time was manipulated. The participants were given either no time to prepare (cue to stimulus interval, CSI: 0 ms), or some time to prepare, for the target language (CSI: 250, 500, and 800 ms). The results revealed that when speakers had no time to prepare, language switching was costly. However, when preparation time was provided, switching costs disappeared. This suggests that there might be no cognitive limitations to the ability to prepare for a language switch, and that, provided enough preparation time, the effort to switch language could be eliminated. This finding might also explain why normal code-switched conversations seem effortless, as speakers typically have ample time to prepare for the language switch.

The source of attention modulations in bilingual language contexts

Bilinguals who switch from a monolingual context to a bilingual context enhance their domain-general attentional system. But what drives the adaptation process and translates into the observed increased efficiency of the attentional system? To uncover the origin of the plasticity in a bilingual's language experience, we investigated whether switching between other types of categories also modulated domain-general attentional processes. We compared performance of Catalan-Spanish bilinguals across three experiments in which participants performed the Attentional Network Test in a mixed context and in two single contexts that were created by interleaving words with flankers. The contexts were related to switching (or not) between languages (Experiment-1) or between low-level perceptual color categories (Experiment-2) or between linguistic categories (Experiment-3). Both switching between languages and linguistic categories revealed increased target-P3 amplitudes in mixed contexts compared to single contexts. These findings can inform the Inhibitory Control model regarding the locus and domain-generality of attentional adaptations.

Assessing the Evidence for Asymmetrical Switch Costs and Reversed Language Dominance Effects - A Meta-Analysis

Two seemingly counterintuitive phenomena - asymmetrical language switch costs and the reversed language dominance effect - prove to be particularly controversial in the literature on language control. Asymmetrical language switch costs refer to the larger costs for switching into the dominant language compared to switching into the less dominant language, both relative to staying in either one language. The reversed language dominance effect refers to longer reaction times when in the more dominant of the two languages in situations that require frequent language switching (i.e., mixed-language blocks). The asymmetrical language switch costs are commonly taken as an index for processes of transient, reactive inhibitory language control, whereas the reversed language dominance effect is taken as an index for sustained, proactive inhibitory language control. In the present meta-analysis, we set out to establish the empirical evidence for these two phenomena using a Bayesian linear mixed effects modelling approach. Despite the observation of both phenomena in some studies, our results suggest that overall, there is little evidence for the generality and robustness of these two effects, and this holds true even when conditions - such as language proficiency and preparation time manipulations - were included as moderators of these phenomena. We conclude that asymmetrical switch costs and the reversed language dominance effect are important for theory development, but their utility for theory testing is limited due to their lack of robustness and the absence of confirmed moderatory variables.

Language Dominance and Sociolinguistic Experience Are Related to Language Control and Domain-General Monitoring Control: An Investigation in Bilinguals Who Live in a Minority/Majority Sociolinguistic Setting

Bilingual language control in production tasks with language switches is supposed to be linked to domain-general cognitive control. In the present study, we investigated the role of language dominance, measured on a continuous scale, in the relationship between measures of language control elicited through language switching in a picture naming task and non-linguistic cognitive control induced by stimulus-response interference in a Simon task. In our sample of bilinguals who speak both a minority and majority language (language pair of Uyghur-Chinese), the results showed that as bilinguals were more L2-dominant, a pattern of reversed asymmetry switch costs in language control, i.e., larger L2 than L1 switch costs, was observed. Furthermore, the findings showed that recent exposure to the L1 minority language was associated with the change in language switch costs in terms of both response latencies and accuracy rates. This suggests a role for sociolinguistic context in bilingual language control. Concerning cross-domain generality, globally sustained language control was found to be correlated with domain-general monitoring control in response latencies for all bilingual participants. It lends support to the idea that bilinguals tap into monitoring control in the context of language switching. Additionally, the cross-domain overlap was found between two non-equivalent measures (global language control vs. cognitive inhibitory control) in response latencies, specifically for L1-dominant bilinguals. This suggests that language dominance may have an impact on cross-domain generality in language-switching processes.

The Simon effect in bilingual language brokers: A role for emotion and proficiency

Aims and objectives/purpose/research questions

Language brokering (LB) is an informal translation experience where bilinguals serve as linguistic and cultural intermediaries for family members. LB may have long-term socio-emotional and cognitive outcomes, yet little is known about its effects on executive functions (EFs). This study examines how first language (L1) proficiency and negative emotions tied to language brokering experiences affect EF performance on a Simon task (ST).

Design/methodology/approach

Fifty-three Mexican American Spanish-English bilinguals with LB experience performed a ST, and reported their feelings towards LB for their mother.

Data and analysis

Mean reaction times (RTs) and accuracy rates for correct ST trials were analyzed using linear mixed effects modeling, with trial type, proficiency and negative emotions tied to LB experience as factors and their interactions as additional predictors.

Findings/conclusions

The L1 proficiency and negative emotions tied to brokering experiences have divergent, but combined effects on EF. Contrary to our hypotheses, low L1 proficiency predicted better performance and the smallest Simon effect was found for brokers with low L1 proficiency and low negative emotional brokering experiences. However, high L1 proficiency predicted better performance (smallest RTs) regardless of negative emotions tied to brokering experiences.

Originality

This study takes a different perspective on the examination of individual differences among bilinguals, in which we examine how negative emotions tied to brokering experiences coupled with L1 proficiency relates to EF performance.

Significance/implications

Our results provide support for the need to understand how individual differences in bilingual language experiences, such as L1 proficiency and negative emotions tied to LB, interact with performance on the ST.

Training in Language Switching Facilitates Bilinguals' Monitoring and Inhibitory Control

In the present study, we use a training design in two experiments to examine whether bilingual language switching facilitates two components of cognitive control, namely monitoring and inhibitory control. The results of Experiment 1 showed that training in language switching reduced mixing costs and the anti-saccade effect among bilinguals. In Experiment 2, the findings revealed a greater decrease of mixing costs and a smaller decrease of the anti-saccade effect from pre- to post-training for the language switching training group compared to the second language training group. Overall, the results suggest that extensive exercise in monitoring and inhibitory control in an experimental setting may enhance the corresponding components of cognitive control. We discuss these findings in the context of the relationship between bilingual language control and executive control.

On the Reliability of Switching Costs Across Time and Domains

Bilingual speakers are suggested to use control processes to avoid linguistic interference from the unintended language. It is debated whether these bilingual language control (BLC) processes are an instantiation of the more domain-general executive control (EC) processes. Previous studies inconsistently report correlations between measures of linguistic and non-linguistic control in bilinguals. In the present study, we investigate the extent to which there is cross-talk between these two domains of control for two switch costs, namely the n-1 shift cost and the n-2 repetition cost. Also, we address an important problem, namely the reliability of the measures used to investigate cross-talk. If the reliability of a measure is low, then these measures are ill-suited to test cross-talk between domains through correlations. We asked participants to perform both a linguistic- and non-linguistic switching task at two sessions about a week apart. The results show a dissociation between the two types of switch costs. Regarding test-retest reliability, we found a stronger reliability for the n-1 shift cost compared to the n-2 repetition cost within both domains as measured by correlations across sessions. This suggests the n-1 shift cost is more suitable to explore cross-talk of BLC and EC. Next, we do find cross-talk for the n-1 shift cost as demonstrated by a significant cross-domain correlation. This suggests that there are at least some shared processes in the linguistic and non-linguistic task.

On the overlap between bilingual language control and domain-general executive control

We explored the overlap between bilingual language control (bLC) and domain-general executive control (EC) by focusing on inhibitory control processes. We tested 62 bilinguals in linguistic and non-linguistic switching tasks for two types of costs, such as the n-1 shift cost and the n-2 repetition cost. In order to explore the involvement of inhibitory control in bLC and EC, we assessed the pattern of switch costs in the two tasks and then we correlated them between tasks. Results showed reduced n-2 repetition costs as compared to n-1 shift costs in the linguistic task only, suggesting that small amount of inhibition were deployed when switching between languages. Importantly, neither the n-1 shift costs nor the n-2 repetition costs were correlated between tasks. These results, supported by additional evidence from the ex-Gaussian analysis, suggest that inhibitory control is differently involved in bLC and in EC.