This study investigates the stability and instability of the language control network in bilinguals using longitudinal resting-state functional magnetic resonance imaging (rs-fMRI) data. We compared the language control network of Chinese university students majoring in English with those not, using three other functional networks as controls. Results indicate that the English major group exhibits reduced stability and increased instability in the language control network compared with the non-English major group. This suggests that second language (L2) learning experience may induce adaptive neural changes. Moreover, the coexistence of stability and instability in the language control network appears less modular in the English major group, implying a more integrated response to language experience. Notably, these results were not observed in the control networks. Overall, these findings enhance the understanding of bilingual language control and the impact of L2 learning on neural plasticity.

Despite often featuring in theoretical accounts, the exact impact of typological similarity on non-native language comprehension and its corresponding neural correlates remains unclear. We examined the modulatory role of typological similarity in syntactic violation processing in the non-native language Spanish, for example [el volcán] versus [*la volcán], and in cross-linguistic influence. Participants were Italian late learners of Spanish (similar language pair) or German late learners of Spanish (less similar language pair). We measured P600 amplitudes, accuracy and response times. In line with our predictions, we found a larger P600 effect and differential CLI effects for Italian-Spanish speakers compared to German-Spanish speakers. Behaviourally, Italian-Spanish speakers responded slower compared to German-Spanish speakers. Together, these results indicate typological similarity effects in non-native comprehension as reflected in a processing advantage for typologically similar languages, but only at the neural level. These findings have critical implications for the interplay of different languages in the multilingual brain.

Although accumulating evidence has demonstrated the foreign language (FL) effect in various scenarios, it remains underexplored whether the FL effect (FLe) would be modulated by the affective valence of scenarios. Hence, we investigated the FLe on the perception of egoistic lies and altruistic lies behaviorally and electrophysiologically. Behavior results showed that compared to using a native language (NL), using a FL led to more agreement with egoistic lies but a comparable level with altruistic lies. Electrophysiological results showed that skin conductance responses (SCRs) elicited by the truth were stronger in the FL compared to that in the NL, whereas SCRs elicited by lies, although strong, exhibited less sensitivity to the altruistic/egoistic condition. SCRs suggested that increased cognitive thinking and reduced affective thinking may contribute to the FLe on egoistic lies dependently or interactively, but these mechanisms cannot accommodate altruistic lies. The results implied the FLe is more stable and obvious in negative contexts.

This study investigated the neural mechanisms underlying bilingual speech perception of competing phonological representations. A total of 57 participants were recruited, consisting of 30 English monolinguals and 27 Spanish-English bilinguals. Participants passively listened to stop consonants while watching movies in English and Spanish. Event-Related Potentials and sLORETA were used to measure and localize brain activity. Comparisons within bilinguals across language contexts examined whether language control mechanisms were activated, while comparisons between groups assessed differences in brain activation. The results showed that bilinguals exhibited stronger activation in the left frontal areas during the English context, indicating greater engagement of executive control mechanisms. Distinct activation patterns were found between bilinguals and monolinguals, suggesting that the Executive Control Network provides the flexibility to manage overlapping phonological representations. These findings offer insights into the cognitive and neural basis of bilingual language control and expand current models of second language acquisition.

Many erroneous literal translations, often produced by low-proficiency bilinguals, can be attributed to a tendency to favor typical translation equivalents; however, the underlying neural mechanism remains poorly understood. This study investigated this typicality effect in real-time translation with the event-related brain potential (ERP) technique. Mandarin Chinese–English bilinguals were presented with a Chinese verb phrase (e.g., kāi chuānghù “open the window” or kāi diànnăo “turn on the computer”) followed by an English verb (e.g., open (a typical translation) or turn on (an atypical translation)) and judged whether the English verb was an appropriate/congruent translation of the verb in the Chinese verb phrase previously presented (e.g., kāi). Compared to typical translation equivalents, atypical equivalents elicited an N400, indicating retrieval difficulty, and an f-PNP in congruent trials, reflecting the effort to inhibit typical translations and integrate atypical ones. This pattern may arise from differences in resting-level activation between typical and atypical equivalents.

Bilingual speakers are prompted to remain in a single language, switch between languages, or codeswitch by regulating the concurrent activation of their language systems and adapting to the demands of the communicative context. Unlike studies that compare language switching in bilinguals in distinct interactional and geographical contexts, this study investigates heritage bilinguals who may be required to manage their home and societal languages differently within the course of a day. We examined how this variation affects linguistic and cognitive factors in spoken production. Critically, picture naming in Spanish and English appeared to rely on different mechanisms of cognitive control: greater reliance on proactive control led to decreased performance in Spanish picture naming but increased performance in English. Although convergent with findings that L2-immersed bilinguals prefer proactive control strategies, the findings with heritage bilinguals suggest that recruitment of cognitive control during speech planning is more dynamic than has been previously reported.

Collocations, defined as sequences of frequently co-occurring words, show a processing advantage over novel word combinations in both L1 and L2 speakers. This collocation advantage is mainly observed for canonical configurations (e.g., provide information), but collocations can also occur in variation configurations (e.g., provide some of the information). Variation collocations still show a processing advantage in L1 speakers, but generally not in L2 speakers. The present eye-tracking-while-reading experiment investigated word order variation by passivising collocations (e.g., information was provided) in L1 and advanced L2 speakers of English. Altering word order did not eliminate the collocation advantage in either L1 or L2 speakers. The collocation effect was independent of contextual predictability and modulated by L2 proficiency. Results support the view that collocations are stored and retrieved via semantic representation rather than as holistic form chunks and that collocation processing does not qualitatively differ between L1 and advanced L2 speakers.

The ability to understand and speak more than one language (i.e., bilingualism) may provide benefits to preserving social cognition against normal age-related deteriorations. This study examined how variations in bilingual language experience influence theory-of-mind (ToM) understanding in late adulthood. One hundred and five cognitively healthy older adults (Mage = 66.23 years, range = 56–79) and 80 young adults (Mage = 22.03 years, range = 19–30), who were bilingual speakers, completed a ToM task battery, a self-report questionnaire on their language background, and a battery of general cognition assessments. We found an overall age-related decline in ToM, where older adults made more errors in inferring others’ mental states compared with young adults. Importantly, an earlier L2 age of acquisition (L2AoA) predicted better ToM performance among older adults, over and above the effects of age, education, and general cognition. The results suggest that early bilingual acquisition may enhance social cognitive processes during development and contribute to intact ToM abilities in older adult bilinguals.

This study tracked the referential production of 25 Japanese-English returnee children for 5 years upon their return to Japan from an English-dominant environment (Mean age = 9.72 at the time of return) and compared their referential strategies to 27 Japanese monolinguals and 27 English monolinguals, age-matched to the returnee’s age at time of return. Returnees used more redundant noun phrases (NPs) in both languages to maintain references compared to monolingual peers. In English, no changes in NP use were noted over time, but increased exposure to English led to fewer redundant NPs when maintaining references. In their native Japanese (L1), returnees used less NPs for maintaining references and more NPs for reintroducing references, indicating improved reference tracking longitudinally. In sum, returnees’ referential production is more sensitive to L1 re-exposure effects than second language (L2) attrition and crucially, increased L2 exposure minimizes redundant referent production among bilingual returnee children.

In recent decades, many eye-tracking studies have demonstrated that both languages of bilingual speakers are activated while processing phonological input in only one. To date, there have been no eye-tracking co-activation studies assessing word recognition among trilinguals. The present research investigates co-activation in all three languages of 48 Russian (Heritage Language)/Hebrew (Societal Language)/English (Third Language) speakers using a trilingual visual world paradigm experiment. The results paint a picture of a highly interactive multilingual lexicon, in line with findings from prior studies on bilingualism. Although accuracy was not affected by competition conditions, reaction times and eye-fixation proportions showed slow-down and distraction in the presence of cross-linguistic competitors, albeit to different extents across the three experiments, evidencing effects of language dominance and acquisition order. This study makes considerable contributions to our understanding of the dynamics of trilingual language processing and discusses findings in the context of existing bilingual processing models.

Bilinguals use languages strategically and make decisions differently depending on the language context. Here, we explored whether verbal feedback modulates language use and risk-taking in bilinguals engaged in a coin-drawing game that incentivises lying. In the game, participants announced bets in Chinese or English, and feedback on the outcome of the current bet was given in the same language. They selected Chinese over English after receiving positive feedback in Chinese, and no language difference was found when feedback was provided in English. They also tended to take more risks after receiving positive than negative feedback. Furthermore, participants were more likely to switch from one language to the other following negative feedback as compared to positive feedback, and when telling the truth, they were faster after negative than positive feedback. Thus, the language in which bilinguals receive feedback constrains language use, which may have implications for understanding interactions in multilingual communities.

Recognition of a word and its meaning benefits from the sensorimotor information about concepts. However, this phenomenon has been underexplored in second-language (L2) speakers who may rely on more “shallow” representations. Using a megastudy dataset, I investigated how sensorimotor strength affects first-language (L1) and L2 word recognition performance. Bayesian hierarchical regressions revealed that variables associated with physical sensations (interoceptive strength, motor action) and communication experience (head or mouth movement, auditory strength) produced strong effects in both groups. On the other hand, variables associated with concrete objects (visual, haptic experience) and with taste/smell (olfactory, gustatory experience) influenced L1 word recognition performance to a larger extent than in L2. In L2, reliance on semantic information during word recognition was reduced, with stronger effects of lexical variables compared to L1. The findings provide implications for understanding L2 processing mechanisms and demonstrate the usefulness of megastudy datasets in investigating L2 conceptual representations.

This study explores lexical borrowing and loanword nativization from a neuro-cognitive perspective testing bi-dialectal speakers of Standard Chinese and Shanghainese Chinese. We created holistic and morpheme-based cross-dialectal loanwords for auditory sentence processing and compared them with Shanghainese-specific words, code-switches, and pre-existing etymologically related words. Participants rated their acceptance of each word, indicating Shanghainese-specific lexical nativeness. GAM analysis of EEG signals revealed that reduced acceptance correlated with frontal positive shifts in ERPs. Holistic loanwords triggered P300-like shifts associated with form-mismatch, whereas morpheme-based loanwords produced LPC-like shifts, suggesting sentence-level re-analysis, and N400-like early frontal negative shifts, indicating lexical integration challenges. Our results indicate that both lexical acceptance and adaptation strategies are pivotal in the cognitive integration of loanwords, revealing distinct neuropsychological stages and pathways in loanword nativization.

During speech production, bilinguals need to encode target words phonologically before articulation, and the encoding units differ across languages. It remains an open question whether bilinguals employ the encoding unit in their L1 or L2 for phonological encoding. The present study examined the primary unit of phonological encoding in L2 speech production by Mandarin Chinese-English bilinguals with high and low L2 proficiency using the picture-word interference paradigm. Results revealed segmental priming effects with one or two segments and syllabic overlap at varied stimulus onset asynchronies (SOAs), for both groups in their L2 speech production. Additionally, the results demonstrated increasing effects with more overlapping segments for both groups, and the facilitation effects decreased as SOA increased. These results indicate that bilinguals encode English words with the segment as a primary planning unit regardless of their L2 proficiency. The time course of segmental encoding in L2 production is also discussed.

Adult heritage language (HL) speakers often exhibit subtle phonetic-phonological variations (“accentedness”) that diverge from the patterns of the language spoken at home. Perception of accentedness may also be influenced by the listener’s linguistic background. This study investigated perceived accentedness in 80 English speech samples from four groups of monolingual English and bilingual English-Hebrew speakers for whom English was either L1 or HL. These samples were evaluated by three rater groups: monolinguals, English-dominant bilinguals, and Hebrew-dominant bilinguals. Our findings confirmed the presence of slight accentedness in HL-English speakers and, to a lesser extent, in immigrants who acquired Hebrew as a second language. While rater background generally had minimal impact, English- and Hebrew-dominant bilinguals differed in their evaluations of the less-accented groups. Individual factors such as lexical proficiency and early language input influenced the HL-English speakers’ accentedness levels. The results are discussed in relation to the Critical Period Hypothesis and its implications.

We conducted a detailed linguistic analysis of Oral Proficiency Interviews (OPIs) from older Spanish-English bilinguals (n = 28) to determine which cognitive, linguistic, and demographic factors predict proficiency. In the dominant language, older age was associated with lower proficiency scores, but aging effects were not significant after accounting for cognitive functioning scores. In the nondominant language, bilinguals with larger vocabulary scores, fewer speech errors, and higher education levels obtained higher proficiency scores. Multiple linguistic submeasures from the OPIs were highly correlated across languages (e.g., fast speakers spoke fast in both languages), but these same measures exhibited significant language dominance effects (e.g., bilinguals spoke faster in the dominant than in the nondominant language). These results suggest it is critical to control for cognitive functioning when examining aging effects on language production, reveal powerful individual differences that affect how people talk regardless of language, and validate the use of the OPI to measure bilingual proficiency.

Simultaneous interpreting (SI) is an intensive multitasking activity that requires coordination of a variety of linguistic and cognitive control mechanisms. Research has shown that interpreters perform better in tasks that require domain-general executive functions (EF), but the question remains whether such cognitive alternation is a result of interpreting experience or it reflects a selection bias that only cognitively capable people are recruited and trained to be interpreters. We examined the cognitive changes experienced by beginner-level students engaged in an intensive, two-week interpreting training programme. Our findings show that: (a) only cognitive flexibility was enhanced by training, together with improvement in SI performance; (b) the three EF subcomponents in their pre-existing forms negatively correlated with training gains; and (c) only pre-existing cognitive flexibility was positively associated with improvement in SI performance. Findings were discussed regarding the relationship between cognitive abilities and the early-stage acquisition of interpreting.

Based on the simple view of reading (SVR), we investigated factors associated with reading comprehension in Second Language (L2) minority children learning a highly consistent orthography through a network analysis. Bilingual and monolingual children participated in the research. Consistent with prior findings, reading speed supported reading comprehension for L1 learners, whereas, for L2 learners, correct decoding carried greater weight than reading speed. In monolingual children, vocabulary and morphosyntactic comprehension contributed jointly and independently to reading comprehension success. However, only vocabulary facilitated reading comprehension in bilingual children, with morphosyntactic skills showing no influence. While monolinguals benefitted from a rich vocabulary and good morphosyntactic knowledge for reading speed and accuracy, in bilingual children, only L2 reading speed was affected by linguistic skills.

Bilingualism delays the onset of dementia symptoms and contributes to cognitive reserve. However, the neural basis of this mechanism remains elusive. The few studies that have investigated neural mechanisms of cognitive reserve and bilingualism have focused on Alzheimer’s disease. This study investigated the neural basis of cognitive reserve among persons with frontotemporal dementia (FTD) using regional brain volumes. Sixty-eight persons with FTD (42 bilinguals and 26 monolinguals) were included. After propensity score matching for age, sex, education, FTD subtype and clinical severity, there were 26 bilinguals and 26 monolinguals. The results showed that bilinguals had reduced thalamic volume compared to monolinguals despite having similar cognitive performance. The results indicate that bilinguals were able to tolerate more severe atrophy compared to monolinguals while maintaining comparable cognitive abilities. Our study therefore suggests that bilingualism contributes to cognitive reserve in persons with FTD.

Many bilinguals speak both languages proficiently and habitually; however, the contexts in which the languages are used can vary. The present study examined the effects of context variation on emotions, comparing a national language used everywhere to a regional language spoken only among family and friends. We found a higher sensitivity to disgust (Experiment 1), a greater enjoyment of humor (Experiment 2) and stronger emotions in response to endearments, reprimands and insults (Experiment 3) with the regional language. The regional language induced stronger emotional responses, even though it was used less frequently than the national language. The effects of the regional language varied depending on the frequency of its use. We propose that these effects on emotions reflect the different opportunities to use the language among family and friends, contexts critical for the acquisition and regulation of emotions and in which emotions are expressed quite vividly.