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.

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.

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.

This paper examined the interaction between narrative performance, language exposure, and standardized measures of morphosyntax and semantics, in bilingual children tested two times, 1 year apart. We aimed to 1) identify the factor structure of oral narrative measures, and 2) examine the direction and strength of the effects of (i) language exposure and (ii) the relationship between language domains and narrative production. A total of 143 Spanish (L1)-English (L2) bilingual children completed a battery of oral narrative and oral language proficiency assessments in Spanish and English at two time points (kindergarten and Grade 1). Factor analyses yielded an identical two-factor structure of bilingual oral narrative measurements, namely productivity (word production) and complexity (sentence structure), in both Spanish and English across the two time points. Cross-lagged analysis showed that narrative production predicted semantics and morphosyntax performance in Spanish and English one year later. Cross-language transfer from L1 to L2 on the complexity of narrative was noted. Language exposure predicted only Spanish narrative production, but not English. These results suggest within- and cross-language transfer, highlighting the importance of L1 language development. In addition, current findings highlight the importance of language exposure for L1 in early school-age children.

This study examined the linguistic and cognitive characteristics of two groups of Italian preschoolers with developmental language disorder (DLD): one group of monolingual Italian speakers and another of Italian-Slovenian bilinguals. The assessment focused on executive functions (EFs) (i.e., phonological working memory and inhibitory control) and linguistic abilities, which involved a multilevel analysis of discourse production. The bilingual group outperformed the monolingual group on tasks measuring EFs. While the two groups showed similar performance across several linguistic measures, the bilingual children demonstrated superior grammatical comprehension, albeit with high variability. A similar level of variability was observed in the bilingual group’s phonological discrimination abilities. Both grammatical comprehension and phonological discrimination were significantly correlated with EFs. These findings are discussed in the context of current theories of linguistic development in bilingual children with DLD.

Effects of language switching in bilinguals have been extensively investigated, but the majority of studies have focused on switching in language production. Here we explored intrasentential switching between Chinese and English, employing a self-paced reading paradigm, with Chinese/English using radically different orthographic systems. In addition, we investigated whether L2 (English) proficiency influences switch costs. Results revealed that switch costs emerged only when switching into L1 (Chinese); by contrast, when switching into L2, a less reliable facilitatory effect was observed. L2 proficiency affected reading speed for English stimuli, but it did not directly modulate switch costs. Moreover, we have integrated various findings from previous research and identified that the use of different comparison patterns is a major contributing factor to the inconsistency in results among prior studies. We suggest that in cross-script language switching, switch costs stem from a general cognitive control mechanism rather than from activation within the bilingual mental lexicon.

In contrast to ample evidence for cross-linguistic priming of monomorphemic words, cross-linguistic representation of affixes is not well understood. The current study examines cross-linguistic prefix priming among early and late English-Spanish bilinguals, focusing on prefixes that have the same form and meaning in the two languages. We first confirm robust prefix priming among English monolingual speakers (Experiment 1). We also observe prefix priming from first-language English to second-language Spanish but only for early bilinguals (Experiment 2). On the other hand, both early and late bilinguals do not show reliable prefix priming effects that are dissociated from orthographic or semantic priming from Spanish to English (Experiment 3) or from Spanish to Spanish (Experiment 4). The results suggest that for early bilinguals, the tested prefixes in their L1 and L2 have shared representations. Less reliable results for late bilinguals may reflect their weaker sensitivity to morphological structure in a second language.

We explored whether bilingual toddlers make use of semantic and phonological overlap between their languages to learn new words. We analysed cross-sectional and longitudinal CDI data on the words understood and produced by 1.0 to 3.0-year-old bilingual toddlers with English and one additional language. Cognates were more likely to be understood and produced compared to non-cognates. Cognate effects were modulated by whether the toddler knew the translation equivalent in the other language, highlighting that young learners are sensitive to the similarities across their languages. Additionally, exploratory analyses suggest that children with smaller vocabularies rely more on translation equivalents to support the acquisition of difficult words. Children with larger vocabulary sizes exhibited no preference for translation equivalents in comprehension, and a preference for new concepts in production. The rapid acceleration of vocabulary growth in the second year of life may explain this developmental change in translation equivalent preference.

This study examined the influence of letter transpositions on morphological facilitation in L1 English and L1 Chinese-L2 English speakers. Morphological priming effects were investigated by comparing morphologically complex primes that either contained transposed-letters (TL) within the stem or across the morpheme boundary, relative to a substituted-letter (SL) control. Within two masked primed lexical decision experiments, the same stem targets were preceded by morphologically related, TL-within, SL-within, TL-across, SL-across, or unrelated primes. Reaction time analyses with morphologically intact primes revealed facilitation in both L1 and L2 English. In L1, TL-within priming was significant, while the magnitude of TL-across priming varied as a function of positional specific bigram frequency and spelling proficiency. In L2, TL-priming was entirely absent. These findings support models of complex word recognition that accommodate relative flexibility in letter position encoding.

Metaphor processing has been mostly researched using the space–valence paradigm, where participants respond to either space–valence congruent or incongruent stimuli. Little attention has, however, been devoted to the role of valence–space associations in bilingual orientational metaphor comprehension. Here, we employed a reaction time method and tested Polish (L1) – English (L2) highly proficient bilinguals, who performed a metaphoricity judgment task to L1 and L2 conceptual metaphoric sentences that were either valence–space congruent (BAD IS DOWN and GOOD IS UP) or incongruent (BAD IS UP and GOOD IS DOWN). The results showed a valence effect, where negatively valenced sentences were evaluated more accurately than positively valenced stimuli. We also found an interaction between valence, congruency and language, such that in both L1 and L2, negatively and positively valenced congruent metaphors were easier and faster to process than those violating the space–valence congruency. Altogether, this study provides a more embodied and experientially grounded approach to studying human cognition, lending credence to the automatic activation of primary metaphorical mappings in the human mind.

The present study examined whether length of bilingual experience and language ability contributed to cross-situational word learning (XSWL) in Spanish-English bilingual school-aged children. We contrasted performance in a high variability condition, where children were exposed to multiple speakers and exemplars simultaneously, to performance in a condition where children were exposed to no variability in either speakers or exemplars. Results revealed graded effects of bilingualism and language ability on XSWL under conditions of increased variability. Specifically, bilingualism bolstered learning when variability was present in the input but not when variability was absent in the input. Similarly, robust language abilities supported learning in the high variability condition. In contrast, children with weaker language skills learned more word-object associations in the no variability condition than in the high variability condition. Together, the results suggest that variation in the learner and variation in the input interact and modulate mechanisms of lexical learning in children.

This study longitudinally modeled home language exposure patterns of US Spanish–English bilingual children between the ages of 4 and 12. Participants were 280 Spanish–English bilinguals (95% Hispanic, 52% female) who were followed for up to 5 years using a cross-sequential longitudinal design. Multilevel linear regression models were used to estimate language exposure trajectories across four home language sources (adults, peers, electronic media and literacy activities) and three language modes (Spanish-only, English-only and bilingual). Results demonstrated that Spanish interactions with both adults and peers declined as children aged, while bilingual interactions showed a distinct increase over time. Conversely, media exposure and engagement in literacy activities increased over time, irrespective of the language used. Children’s age of first English exposure and current school English exposure also influenced language contact and use in the home. These findings approximate an 8-year exposure trajectory across a continuum of bilingual experiences.

We investigated the extent to which executive functions (EFs) are recruited in language switching in children in a cued picture-naming (CN) task. We expected to find associations between CN and EF tasks measuring inhibitory control and shifting. Another goal was to compare parent-reported children’s everyday language control ability at home with their switching ability in the CN task and EF performance. The participants were mostly 5–7-year-old Norwegian–Spanish and Finnish–Swedish-speaking children (N = 45). The analysis was preregistered. Unexpectedly, the primary accuracy analysis showed positive associations between CN switching costs and EF performance in only one of the EF tests, flanker, and CN mixing costs were predicted only by the color-shape switch costs. Children’s everyday language control ability did not show consistent significant associations with lab measures. Our study provides weak evidence for the view that EFs are engaged in language control when children have some years of bilingual experience.

There is evidence to suggest that the effects of bilingualism on executive functions (EFs) need to be examined along a continuum rather than a dichotomy. The present study addressed this need by examining the influence of different bilingual experiences on executive functioning using a Flanker and Stroop mouse-tracking task that taps into more dynamic cognitive processes than typical behavioral paradigms. We sampled 98 bilingual young adults and investigated conflict and sequential congruency effects (SCEs). We found that mouse-tracking metrics captured links that were not identified with overall reaction times. SCEs were more sensitive to detecting relations between L2 experiences and EF than simple conflict effects. Second-language age of acquisition and L1/L2 switching frequency consistently predicted EF outcomes. This association was moderated by the attentional demands of the task. These findings highlight the complexity of the effects of bilingualism on cognition, and the use of more sensitive measures to capture these effects.

English as a second language (L2) has become the medium of instruction in numerous contexts even though many people may have difficulties to read and study in L2. According to the self-regulated framework, metacognitive strategies are essential to achieve successful learning, but they are resource-consuming and their use might be compromised in demanding contexts such as learning in L2. In Experiment 1, nonbalanced bilinguals read high- and low-cohesion texts in L1 and L2 and self-rated their learning using a judgment of learning (JOL). Then, they answered open-ended questions and responded a customized questionnaire regarding their strategies. In Experiment 2, we introduced two bilingual groups varying in L2 proficiency. Overall, participants could adjust their JOLs and detect the difficulty of the texts correctly in L1 and L2. However, results evidenced some nuances in learning strategies related to L2 proficiency. We discuss these findings within the context of the self-regulated learning.

This study investigated the role of temperament in oral language development in over 200 Mandarin and Cantonese speakers in the Growing Up in New Zealand pre-birth longitudinal cohort study. Mothers assessed infant temperament at nine months using a five-factor Infant Behaviour Questionnaire-Revised Very Short Form. They also reported on children’s vocabulary and word combinations at age two using adapted MacArthur-Bates Communicative Development Inventory short forms. Regression analyses were employed to examine unique links between infant temperament and language, respectively, controlling for demographic factors. Fear was associated with larger English vocabularies for English-Mandarin speakers and larger Cantonese vocabularies for Cantonese speakers. Orienting capacity was associated with more advanced word combinations for Mandarin speakers, whereas negative emotionality was associated with less advanced word combinations for Cantonese speakers. Positive affect/surgency was associated with more advanced word combinations for English-Cantonese speakers. This study revealed predictive patterns of infant temperament across Chinese-speaking children’s multiple languages.

Can exposure to a foreign language in the first year of school enhance divergent thinking skills? Ninety-nine monolingual children from predominantly White neighbourhoods (MAge = 57.7 months, SD 1.2; 47 girls) attending bilingual schools, schools with weekly foreign language lessons, or schools without a foreign language provision (= controls) completed divergent thinking and executive function tasks at the beginning of the school year and 24 weeks later. The groups did not differ on creativity measures at the beginning of the school year. Only bilingual school children and weekly language learners improved divergent thinking at the second testing point, with the former significantly outperforming controls on creative fluency and flexibility. Improvements could not be explained by executive function development. Therefore, a considerable amount of exposure to a foreign language in early formal education appears to boost creative thinking.