Unbalanced Chinese-English Bilinguals Research Articles

Modality-general and modality-specific bilingual control mechanisms in spoken and written productions

Abstract Do bilinguals have similar bilingual control mechanisms in speaking and writing? The present study investigated the patterns of switch costs (reflecting reactive language control) and mixing costs (reflecting proactive language control) between Chinese (L1) and English (L2) in spoken and written productions and whether these patterns could be modulated by response-stimulus intervals (RSIs). In two experiments, unbalanced Chinese–English bilinguals completed a cued language switching task in spoken naming (Experiment 1) and written naming (Experiment 2), respectively. The results revealed asymmetrical switch costs (i.e., the larger cost in L1 than in L2) in spoken and written productions in the short RSI condition. However, there were asymmetrical mixing costs in spoken production and symmetrical mixing costs in written production both in the short and long RSIs. These findings suggest that for spoken and written productions, reactive language control operates in similar mechanisms, while proactive language control operates in specific mechanisms.

The effect of categorization levels on semantic access: eye-movement evidence from unbalanced Chinese-English bilinguals

The effect of categorization levels on semantic access: eye-movement evidence from unbalanced Chinese-English bilinguals

Bidirectional interaction between language control and domain-general executive control in unbalanced Chinese-English bilinguals

Recent research has shown that bilinguals outperform monolinguals on tasks requiring non-linguistic executive control skills, thereby generating an interest in the relationship between bilingual language processing and non-linguistic control abilities. Based on this, the present study further examined the bidirectional interaction between language control and non-linguistic control in unbalanced Chinese-English bilinguals. These bilinguals completed a Flanker task in three types of language control contexts (i.e., L1, L2, and Mixed language contexts) in the interleaved word-comprehension-to-Flanker sequence and performed a picture-word matching task in three types of non-linguistic executive control contexts (i.e., color, shape and color-shape mixed contexts) in the interleaved color-shape-switching-to-word-comprehension sequence. The results showed that the Flanker effect in mixed language context was smaller than in single (L1 and L2) context, suggesting language control leads to a better non-linguistic control ability. Additionally, the language switching cost was found smaller in the mixed task context (color/shape switching), indicating that non-linguistic control can enhance the language control ability. Therefore, we conclude that there is a bidirectional interaction between language control and non-linguistic control even in unbalanced bilinguals.

The Effects of Cognitive Control on the Subcomponents of Language Control in Spoken and Written Productions.

The present study aimed to investigate whether and how the subcomponents of language control during spoken and written productions were modulated by cognitive control. In the current study, unbalanced Chinese-English bilinguals were recruited from a convenience sample at a university to complete the cued language naming task in spoken production and written production, which measured the local language control (as indexed by language switch costs) and the global language control (as indexed by language mixing costs and reversed language dominance effect). In addition, all the participants performed the Simon task, which measured their general inhibitory control ability by calculating the Simon effect, and performed the AX-CPT task to measure their reactive/proactive control preference by calculating their BSI score. All the data were collected using E-prime 2.0 and analyzed in R. Linear mixed-effect model analyses were conducted to reveal the similarities and differences between spoken production and written production for the first-step analysis. Then, the Simon effect and BSI scores were inserted into the mixed-effect models of the switch costs and mixing costs in spoken production and written production, respectively, to explore whether cognitive control can predict the subcomponents of bilingual control. The results showed similar symmetrical switch costs in spoken and written modalities. In contrast, there was a reversed language dominance effect (in the mixed language context) and asymmetrical mixing costs in spoken production but neither in written production. Furthermore, we found that the Simon effect significantly negatively predicted the L2 mixing costs in spoken production, whereas the BSI score significantly negatively predicted both the L1 and L2 mixing costs in written production. The findings indicated that, for unbalanced bilinguals, local language control is shared between two modalities, while global language control is modality-independent between spoken production and written production. More importantly, the findings also suggested that global language control in spoken production relies more on the individuals' general inhibitory control, while in written production, it relies more on their cognitive control strategy. Global language control in spoken and written productions separately engages specific aspects of cognitive control, which may account for different forms of processing in global language control between speaking and writing.

Language-emotion interaction modulates selective attention to a speaker’s eyes and mouth: evidence from Chinese-English bilinguals

ABSTRACT Speech listeners focus on a speaker's face to acquire different information in social communication. Fixation on the mouth associates with language processing and attention to the eyes is mainly driven by social/emotional cues. Here, we investigated how selective attention to the eyes and mouth would vary with language-emotion interaction during speech processing when unbalanced Chinese-English bilinguals [Chinese, the first language (L1); English, a later-learned language (LX) of upper-intermediate proficiency] viewed a speaker narrating stories of different valence in their L1 and LX. Results showed that when listening to negative stories in Chinese relative to English, bilinguals attended to the eyes more, indicating that LX emotionality is weaker than that in L1, reducing gaze to the eyes where human adults primarily seek for emotional cues. In Chinese, compared with neutral speech, both positive and negative stories increased mouth attention and this effect was not observed in English, suggesting a particularly important role of the mouth in processing emotional information in speech and confirming emotionality reduction in LX. Our study reveals for the first time how linguistic and emotional cues integrated in speech alters attention allocation on speakers’ face to facilitate both speech comprehension and emotional perception in social communication.

Control mechanisms in voluntary versus mandatory language switching: Evidence from ERPs

The present study measured event-related potentials (ERP) and behavioral performance to examine whether inhibitory control is involved in voluntary language switching, and if so, to explore the differences in inhibitory control between voluntary and mandatory language switching. Unbalanced Chinese-English bilinguals completed two picture naming tasks: one involving mandatory language switches and one in which participants could voluntarily switch between the two languages. Behavioral data showed significant switch costs and a reversed language dominance effect in both switching tasks. Critically, both effects were larger in mandatory compared to voluntary switching. ERP results revealed that neural switch costs during mandatory switching was significantly different than voluntary switching in both N2 and LPC amplitudes. In contrast, a significant difference in the reversed language dominance effect between both tasks was only observed in LPC amplitude. Together, these findings suggest the involvement of inhibitory control in both mandatory and voluntary language switching, but the degree of inhibition and the time-course of control processes between both tasks appear to be distinct.

Second Language Proficiency Modulates the Dependency of Bilingual Language Control on Domain-General Cognitive Control.

The relationship between bilingual language control and domain-general cognitive control has been a hot topic in the research field of bilingualism. Previous studies mostly examined the correlation between performances of bilinguals in language control tasks and that in domain-general cognitive control tasks and came to the conclusions that they overlap, partially overlap, or are qualitatively different. These contradictory conclusions are possibly due to the neglect of the moderating effect of second language (L2) proficiency, that is, the relationship between bilingual language control and domain-general cognitive control might vary with the L2 proficiency of bilinguals. To examine this hypothesis, we recruited 36 unbalanced Chinese-English bilinguals to perform the Simon task (to assess domain-general cognitive control), Oxford Placement Test (to assess L2 proficiency), and picture naming tasks in single-and dual-language contexts (to evoke local and global language control). We find that Simon scores positively predicted switching costs in bilinguals with low L2 proficiency, but not in bilinguals with high L2 proficiency. Furthermore, Simon scores positively predicted mixing costs in bilinguals with high L2 proficiency, but not in bilinguals with low L2 proficiency. These results verify the moderating effect of L2 proficiency on the relationship between bilingual language control and domain-general cognitive control, that is, bilinguals with more proficient L2 rely on domain-general cognitive control less for local language control and more for global language control. This may imply a shift from local to global for the dependency of bilingual language control on domain-general cognitive control during the L2 development of bilinguals.

Influences of Language Shift on Speech Fluency in Memory Production of Unbalanced Chinese-English Bilinguals

Language shift at encoding and retrieval has been demonstrated to influence memory. However, previous studies of language shift mostly focused on memory accuracy, leaving its effect on fluency of memory production neglected. The current study sets out to investigate how encoding language and delay interval influence speech fluency in memory production. In the study, 60 Chinese ESL learners were asked to verbally retell two stories in immediate or delayed memory tests. One story was learned in English but recalled in Chinese, and the other was learned and recalled both in Chinese. The fluency of their speech reproduction during story recall was manifested by production fluency and pause rate. The results show that encoding in English and retrieving in Chinese leads to more pauses and lower fluency than encoding and retrieving both in Chinese. However, the language shift effect on speech production diminishes after 24 hours’ delay. The results suggest the key role of delay interval in modulating language shift effect and shed light on bilingual memory and bilingual education.

Language Shift Effect on Memory Generalization of Chinese-English Bilinguals

Language shift occurs when people learn information in one language but recall it in another language. This mismatch between encoding and retrieval language is found to impair memory accuracy when memory is tested immediately after learning. However, does the observed language shift effect still exist after a certain period of delay? Would it influence other aspects of memory, especially memory generalization? To address these two questions, we performed a memory experiment among unbalanced Chinese-English bilinguals. In the experiment, participants were required to read two stories (one in English, one in Chinese) and to retell the stories in Chinese from their memories afterward. Delay interval was manipulated in the experiment where participants either took memory recall tests immediately after story-reading or after 24 hours' delay. To analyze memory generalization, we coded the generalized words participants used to retell the stories. The results suggest that language shift (encoding in English and retrieving in Chinese) leads to a more generalized description in a memory recall task. However, the observed language shift effect disappears after 24 hours' delay. It can be concluded that language shift impacts bilingual learners' memory generalization in immediate recall tests, but such effect disappears after 24 hours' delay, which indicates the key role of delay interval in modulating language shift effect.

Language switching training modulates the neural network of non-linguistic cognitive control.

Bilingual language experience, such as switching between languages, has been shown to shape both cognitive and neural mechanisms of non-linguistic cognitive control. However, the neural adaptations induced by language switching remain unclear. Using fMRI, the current study examined the impact of short-term language switching training on the neural network of domain-general cognitive control for unbalanced Chinese-English bilinguals. Effective connectivity maps were constructed by using the extended unified structural equation models (euSEM) within 10 common brain regions involved in both language control and domain-general cognitive control. Results showed that, the dorsal anterior cingulate cortex/pre-supplementary motor area (dACC/pre-SMA) lost connection from the right thalamus after training, suggesting that less neural connectivity was required to complete the same domain-general cognitive control task. These findings not only provide direct evidence for the modulation of language switching training on the neural interaction of domain-general cognitive control, but also have important implications for revealing the potential neurocognitive adaptation effects of specific bilingual language experiences.

Language context tunes brain network for language control in bilingual language production

When bilinguals intend to speak in their first (L1) or second language (L2) according to the environment, a brain network involving cortical-subcortical regions is recruited to resolve cross-language interference. Research has found that the activation of these brain regions varies with language contexts. However, previous studies have not yet examined adaptive changes in the interactions of brain regions for different language contexts. To address this gap, we adopted extended unified structural equation modeling (euSEM) to identify the connectivity patterns of the bilingual control network. Twenty-one unbalanced Chinese-English bilinguals were instructed to name pictures in L1-single, L2-single, and dual-language contexts while undergoing functional magnetic resonance imaging (fMRI). We found that unbalanced bilinguals relied on a more functional integrated brain network, which was reflected by clearer core-periphery structures and increased global efficiency, in dual-language and L2-single contexts compared to L1-single context. Furthermore, the pattern of brain connectivity in the dual-language context was more similar to that in the L1-single context than the L2-single context. More importantly, we found more similarities between the connectivity patterns of dual-language and L1-single contexts in bilinguals with lower inhibitory control abilities. These findings provide the first connectivity evidence for the effect of language context on the bilingual language control network, which inhibits the base language and underpins bilinguals’ change along the monolingual-bilingual mode continuum.

Effects of language context on executive control in unbalanced bilinguals: An ERPs study.

The influence of the language context on language control has been widely discussed in the bilingualism literature, and there is an increase in studies examining the effect of language context on domain-general executive control. However, it remains unclear how language contexts affect executive control performance. In the present study, we created single- and mixed-language comprehension contexts. Unbalanced Chinese-English bilinguals completed a modified flanker task that was interleaved with a single-language or mixed-language picture-word matching task. The effects of language comprehension context on language control were reflected by the N2 and LPC effects. Executive control processes also differed depending on the language comprehension context, with faster behavioral responses and larger N2 but smaller P3 electrophysiological components in the mixed-language context. Moreover, the LPC amplitude in the mixed-language context predicted the behavioral performance in the executive control task. These findings suggested that flexible language control during language comprehension altered executive control processes in unbalanced bilinguals.

Interactive influence of self and other language behaviors: Evidence from switching between bilingual production and comprehension.

The neural mechanisms underlying one's own language production and the comprehension of language produced by other speakers in daily communication remain elusive. Here, we assessed how self‐language production and other‐language comprehension interact within a language switching context using event‐related functional Magnetic Resonance Imaging (er‐fMRI) in 32 unbalanced Chinese‐English bilinguals. We assessed within‐modality language interference during language production and comprehension as well as cross‐modality interference when switching from production to comprehension and vice versa. Results revealed that the overall effect of production (across switch and repeat trials) was larger in the cross‐modality than within‐modality condition in a series of attentional control areas, namely the left dorsolateral prefrontal cortex, anterior cingulate cortex and left precuneus. Furthermore, the left precuneus was recruited more strongly in switch trials compared to repeat trials (i.e., switching costs) in within‐production conditions but not in the cross‐modality condition. These findings suggest that switching from production to comprehension recruits cognitive control areas to successfully implement switches between modalities. However, cross‐language interference (in the form of language switching costs) mainly stems from the self‐language production system.

Role of joint language control during cross-language communication: evidence from cross-frequency coupling.

How do bilingual interlocutors inhibit interference from the non-target language to achieve brain-to-brain information exchange in a task to simulate a bilingual speaker-listener interaction. In the current study, two electroencephalogram devices were employed to record pairs of participants' performances in a joint language switching task. Twenty-eight (14 pairs) unbalanced Chinese-English bilinguals (L1 Chinese) were instructed to name pictures in the appropriate language according to the cue. The phase-amplitude coupling analysis was employed to reveal the large-scale brain network responsible for joint language control between interlocutors. We found that (1) speakers and listeners coordinately suppressed cross-language interference through cross-frequency coupling, as shown in the increased delta/theta phase-amplitude and delta/alpha phase-amplitude coupling when switching to L2 than switching to L1; (2) speakers and listeners were both able to simultaneously inhibit cross-person item-level interference which was demonstrated by stronger cross-frequency coupling in the cross person condition compared to the within person condition. These results indicate that current bilingual models (e.g., the inhibitory control model) should incorporate mechanisms that address inhibiting interference sourced in both language and person (i.e., cross-language and cross-person item-level interference) synchronously through joint language control in dynamic cross-language communication.

Language context modulates executive control in bilinguals: Evidence from language production

The effect of language context on bilingual language control has been widely studied, but research examining how these contexts affect executive control is relatively limited. In the present study, we used EEG to examine how language context in production influences executive control in bilinguals. A single group of unbalanced Chinese-English bilinguals completed a modified Flanker task interleaved with a picture-naming task, such that executive control performance was measured in three contexts: Chinese, English, and mixed-language. Event-related potentials (ERPs) revealed larger N2 amplitudes and smaller P3 and LPC (late positive component) amplitudes for the mixed-language context than the single-language context across both congruent and incongruent trials. Moreover, during the language production task, LPC amplitudes in mixed-language context were smaller than in the single-language contexts. These findings suggest that language contexts modulate both bilingual language control and domain-general executive control.

The development on transposed-letter effect in English word recognition: Evidence from Late unbalanced Chinese-English bilinguals

The present study examined the orthographic processing of English visual word recognition in adult Chinese-speaking English learners under the framework of the multiple-route model of reading development. Two groups of adult learners with high and low English proficiency finished a forward-masked lexical decision task. The results showed a complicated scenario on transposed-letter effects, implying that the late unbalanced Chinese-English bilinguals with low English proficiency still needed to adopt a letter-to-letter reading strategy, and that the L2 users with high English proficiency also had not properly developed the fine-grained orthographic route even they had a long experience of English learning in the foreign language learning settings in China. Overall, it is suggested that late unbalanced Chinese-English bilinguals generally follow a path similar to that of native readers in acquiring English visual word recognition skills developed from the letter-to-letter reading strategy to the parallel orthographic processing strategies. However, since L2 users usually have no or limited spoken vocabulary of English before accessing printed words and inadequate supervision in developing L2 word reading skills, their development would be much slower than that of English native speakers.

Role of language control during interbrain phase synchronization of cross-language communication

The inhibitory control (IC) model proposes that language control plays an important role in suppressing cross-language interference within a bilingual individual's cross-language output. However, it may also play a role in dynamic interactive communication. Accordingly, the current study used the electroencephalogram (EEG) to simultaneously record neural oscillations from 13 paired unbalanced Chinese-English bilinguals during cooperative picture-naming in either first language (L1) or second language (L2) according to cues. We found that the speaker and listener achieved synchronization by inhibiting interference from the nontarget language (cross-language interference) and partner (interpersonal interference) through language control. Furthermore, the more the language control resources were used, the higher the level of neural synchronization. These findings indicate that language control is associated with neural synchronization of cross-language communication. Altogether, the IC model should highlight the role of language control in inhibiting not only cross-language interference but also interpersonal interference during dynamic cross-language communication.

The neurocognitive mechanisms of semantic gender processing in L1 and L2 personal nouns by Chinese-English bilinguals

ABSTRACTSemantic gender agreement processing can be a problem for Chinese-English bilinguals, but it is still unclear whether the problem originates from a processing deficiency in the antecedent. To clarify this issue, the present study conducted two ERP experiments in which unbalanced Chinese-English bilinguals read L1 and L2 sentences describing pictures just presented. ERP responses to the personal nouns that were either congruent or incongruent in gender with the picture referents were recorded and analysed. In the L1, a gender incongruity effect (P600) was observed. In the L2, the more proficient group demonstrated the same gender incongruity effect as in the L1, while the less proficient group manifested a pattern of N400 plus late P600 (700–900 ms). These findings indicate that Chinese-English bilinguals were able to access in time semantic gender information in both L1 and L2 personal nouns, but the exact mechanisms differed qualitatively between learners differing in L2 proficiency.

Second language (L2) proficiency, socioeconomic status (SES), and intelligence (IQ) are significant predictors of cognitive control differences among young adult unbalanced Chinese–English bilinguals

The current study investigates how second-language (L2) proficiency contributes to cognitive control differences among three groups of unbalanced Chinese–English bilinguals matched for socioeconomic status (SES), intelligence (IQ), education, age, culture, and L1 background. A Flanker task and the Wisconsin Card Sorting Test (WCST) were administered to measure conflict monitoring, inhibition, and mental set shifting. ANOVA analyses revealed faster performance for the High-L2 Group compared to the Low-L2 Group in the congruent, neutral, and incongruent conditions of the Flanker task. However, there were no group differences on the WCST. Multiple step-wise regression analyses showed that L2 proficiency was a predictor for the Flanker task performance in all three conditions, SES in the neutral and the incongruent condition, and IQ in the congruent condition. These results suggest that L2 proficiency, along with SES and IQ, contribute significantly to cognitive control differences in conflict monitoring among young-adult bilinguals.

The Influence of Second Language (L2) Proficiency on Cognitive Control Among Young Adult Unbalanced Chinese-English Bilinguals.

The current study investigates the influence of L2 proficiency on cognitive control among three matched groups of unbalanced Chinese-English bilinguals. Flanker task was administered to measure conflict monitoring and inhibition, and Wisconsin Card Sorting Test (WCST) to measure mental set shifting. ANOVA analyses of the Flanker results showed no differences in inhibition across all groups and no interaction between group and condition. However, the Flanker results showed faster performance for the highest L2 proficiency group relative to the lowest L2 proficiency group in all conditions (incongruent, neutral, and congruent), which reflects better ability of conflict monitoring. Finally, ANOVA analyses of the WCST results showed no differences across all groups. These results altogether suggest that L2 proficiency has significant influence on cognitive control, but only in conflict monitoring, not in inhibition or mental set shifting.