Color perception is influenced by lexical categories. Previous research shows that languages partition the color spectrum in unique ways, leading to faster discrimination between colors belonging to different categories (Kay & Kempton, 1984; Winawer et al., 2007). The influence of color names on perception in bilinguals is not conclusive. In Italian, dark and light blues are distinguished as separate categories (blu and azzurro), while French speakers use bleu for both. We tested French–Italian bilinguals in a speeded color discrimination task, where language was indirectly involved, and compared the results with monolingual controls. Bilinguals tended to align with Italian monolinguals, as Italian categories dominated their perception of blue hues, but also showed some French-like behavior, reflecting the stability of the dark blue category. Bilinguals, therefore, process color through a mix of both languages, suggesting that language plays a key role in bilingual cognition, whose perception is shaped by more complex processes.

This study examines the underlying mechanisms driving the bilingual advantage in learning English as a foreign language (EFL) among kindergarten-aged children. Participants included 85 Dutch-speaking monolinguals and 34 bilingual children. We assessed children’s English vocabulary and grammar as the outcome variables. Furthermore, phonological awareness, executive functions and motivation to learn English were measured as potential mediators of the bilingualism–EFL relationship. We also controlled for child age, non-verbal IQ, Dutch (majority language) proficiency, intensity of school English instruction, parental education and exposure to English activities. Results showed that bilingual children outperformed monolinguals in English receptive vocabulary, but only for noncognate words; no differences emerged for cognate words or English grammar. However, none of the proposed mediators explained this advantage. Findings are discussed in terms of why the effect was limited to vocabulary and potential alternative mechanisms not explored in the present study.

The study investigated the strength of L2 form-meaning connections among advanced L2 speakers. Two unmasked intralingual L2 semantic priming experiments were conducted, with lexical decision and semantic categorization tasks. Thirty-eight native English speakers and 40 advanced Chinese learners of English were tested in each task. The stimuli involved L2 word targets that were preceded by either a related L2 prime or an unrelated one. Previous research has used the lexical decision task in this investigation, and the semantic task was also used in the present study to boost the involvement of conceptual connections in L2 processing. Consistent with previous findings, native English speakers showed a reliable priming effect in both tasks, but English L2 speakers showed no priming effect in either task. No task effect was found in either group. The findings provided further evidence for a weaker L2 form-meaning connection among advanced L2 speakers.

Due to the lack of explicit word boundary markers, L2-Chinese learners have shown some difficulties in Chinese word segmentation. This study aimed to tackle the possible reasons of L2-Chinese learners’ difficulties in word segmentation: L1-biased processing strategy or developing mental representations of Chinese compound words, or both. In an eye-tracking experiment, high-frequency two-character Chinese compound words were used as targets. These compound words were embedded in sentences where their first component characters with prior verbs were manipulated to be either plausible or implausible, while the whole compound words were always plausible. Sentences were presented in character-spaced or word-spaced style. High-proficiency L2-Chinese learners and native Chinese speakers participated. Results revealed non-native-like patterns of L2-Chinese learners: they holistically processed compound words only in the word-spaced condition, while native speakers did so regardless how sentences were presented. The findings indicated that high-proficiency L2-Chinese learners’ difficulty in word segmentation is predominantly caused by their L1-biased processing strategy.

This retrospective cohort study examined the relationship between a continuous measurement of bilingual engagement (operationalized as language entropy) and cognitive aging in regional minority language speakers. We drew Frisian–Dutch bilinguals (n = 7,448) and Low Saxon–Dutch bilinguals (n = 10,114) from the Lifelines Cohort Study and included participants aged 20–80, enabling an adult lifespan perspective. Cognitive functioning was measured using the Cogstate Brief Battery, which assesses processing speed, attention, working memory and recognition memory. We did not observe a robust relationship between bilingual engagement and cognitive functioning. Our results suggest that bilingual engagement does not play a key role in processing speed, attention, working memory and recognition memory performance in Frisian–Dutch and Low Saxon–Dutch bilinguals. Implications for the bilingual engagement measurement and potential investigations into regional minority language bilingualism and cognition are discussed.

We explored the relationships between L2 utterance fluency and cognitive fluency in monologic and dialogic tasks. The study involved 136 Chinese university-level English learners. Utterance fluency was measured through speed, breakdown, and repair fluency aspects. Cognitive fluency was indicated by L2 lexical and syntactic processing efficiency measures. Stepwise regression models, including metrics of L2-specific cognitive fluency, L2 knowledge, and L1 utterance fluency as predictors, targeted L2 utterance fluency as the dependent variable. We found that L2 cognitive fluency predicted limited variance in utterance fluency, with its influence more evident in monologues. L2 lexical processing efficiency paralleled syntactic processing efficiency’s importance in the monologic task but surpassed it in dialogues. Moreover, L2 processing speed had a more significant impact on utterance fluency than processing stability across both contexts. We suggest that cognitive fluency is not the sole determinant of utterance fluency; L2 knowledge and L1 utterance fluency play non-negligible roles.

We investigate timing and eye-movement behavior during semantic prediction in L1 and L2 speakers of English using the Visual World Paradigm, additionally exploring speech rate. We differentiate first-stage predictions, considered to be automatic and relatively cost-free, from second-stage predictions, which are non-automatic and more cognitively demanding, with differences between L1 and L2 speakers believed to arise in second-stage predictions. We found no differences in the divergence of looks to the target in first- or second-stage predictions across groups. However, speech rate played an important role. Both L1 and L2 speakers showed similar first-stage predictions at slower speech rates, but L1 speakers showed earlier predictions as the speech rate increased. L2 speakers showed reduced and more variable second-stage predictions, suggesting they were impacted during the more demanding second-stage prediction. This may indicate a wait-and-see strategy to help reduce costs associated with second-stage prediction.

We tested masked morphological priming effects with prefixed and suffixed words in L2 speakers of German with L1 Turkish, a language in which prefixes are virtually absent. We found weaker prefixation than suffixation priming, suggesting that cross-linguistic morphological differences between speakers’ L1 and L2 may influence L2 morphological processing. We additionally compared our findings to those of a previous study involving L1 Russian-L2 German speakers and L1 German speakers (Ciaccio & Clahsen (2020). Variability and consistency in first and second language processing: A masked morphological priming study on prefixation and suffixation. Language Learning, 70(1), 103–136). The magnitude of prefixation versus suffixation priming of our group was significantly larger than that reported for the L1 Russian-L2 German group, further corroborating the cross-linguistic hypothesis. However, we found no significant difference between our group and L1 German speakers. Therefore, we additionally consider the hypothesis of a general processing disadvantage for prefixed words as an alternative explanation. We conclude that several factors may contribute to why prefixation, in some studies, proves to be more challenging than suffixation, cross-linguistic influences being possibly just one of them.

This study examined the relationship between intelligibility and comprehensibility in second language speech. Four extended speech samples from 50 speakers spanning a wide range of proficiency were drawn from archived test data. These samples were listened to by 570 English users, who provided comprehensibility ratings and transcriptions to measure intelligibility. The relationship between intelligibility and comprehensibility was strong (r = .81, ⍴ = .88) and nonlinear. A segmented regression model suggested a breakpoint for intelligibility scores (transcription accuracy) at 64%, below which speakers were perceived as uniformly hard to understand and above which increased intelligibility was strongly associated with higher comprehensibility.

Learning to map novel words onto their intended referents is a complex challenge, and one that becomes even harder when acquiring multiple languages. We investigated how label mixing affected learning novel words in one versus two languages. In a cross-situational word learning study, 80 adult participants learned either one-to-one word–object mappings, or two-to-one mappings, reflecting different challenges in learning one or two languages. We manipulated whether mappings co-occurred locally, where repetitions were prevalent, or whether co-occurrences were more distributed throughout exposure. Learners acquired two-to-one mappings better when they did not occur in local co-occurrences, but there was no effect of learning conditions for one-to-one mappings. Whether participants were proficient or not in an additional language did not have an observable effect on the learning. We suggest that local co-occurrences of multiple labels, as in language mixing environments, increase the challenge of learning words, though this effect may be only short-lived.

Embodied cognition theory posits that language comprehension is grounded in sensorimotor experience. For instance, abstract concepts such as perceived power are metaphorically associated with spatial information such as physical size. Here, using a size judgement task, we investigated whether perceived power embodiment differs between languages in Chinese–English bilinguals. Asked to make judgements regarding the physical size of words, participants responded faster and made fewer errors to high-power words (e.g., king) presented in bold and large font than in thin and small font, while no such effect was found for low-power words. Furthermore, this congruency effect was stronger in bilinguals’ L1 (Chinese) than in their L2 (English). Thus, while embodiment of perceived power is detectable in both languages of bilinguals, it appears weaker in the L2. This study highlights cross-linguistic similarities and differences in the embodiment of abstract concepts and contributes to our understanding of conceptual knowledge grounding in bilinguals.

Previous research using cued language switching paradigms has shown a reversed language dominance effect in highly proficient bilinguals, wherein the dominant language is most inhibited. This study investigated cued language switching in highly proficient Spanish–Basque bilinguals (N = 50) using pupillometry, a novel measure of switching cost that tracks cognitive load via pupil size. Response times during cued picture-naming showed faster responses on non-switch than switch trials and faster responses in Basque than in Spanish. These findings suggest balanced proficiency across languages, with Spanish showing overall slowed responses, indicating a reversed dominance effect. Pupil data revealed larger pupil responses for Basque, the less dominant language, suggesting greater cognitive load despite faster naming. This indicates more attentional allocation or activation of the non-dominant language during cued language switching. These results provide insights into the cognitive processes involved in bilingual switching and highlight the value of using pupillometry to explore bilingual language processing.

Whether bilingualism confers non-linguistic cognitive advantages continues to generate both interest and debate in the psychological sciences. In response to mixed reports and methodological critiques, researchers have embraced more rigorous practices when investigating bilingual effects, including those in the domain of cognitive control. Despite considerable advances, one significant issue persists: the assumption that task performance remains stable over time. To address this, the present study investigated the relationship between bilingual language experience and Simon task performance modeled as a continuous function of time. In a sample of Mandarin-English bilingual young adults, we identified distinct patterns of results across both conventional and time-sensitive performance trajectory measures with each supporting a different relationship between language experience and cognitive control. Results suggest that reliance on conventional performance measures may be partially responsible for mixed results, necessitating reevaluation of how bilingual effects on cognitive control manifest and which analysis methods best support their identification.

How does bilingualism affect orthographic processing across languages with different structures? This study investigates masked transposed-letter (TL) priming in Arabic-English bilinguals, comparing Arabic (a Semitic language with rigid orthography and weak TL effects) with English (an Indo-European language with flexible letter coding and strong TL effects). Using lexical decision tasks, we tested whether exposure to English enhances letter-coding flexibility in Arabic. Results showed robust TL priming in both languages, indicating that bilingual experience with English modifies Arabic orthographic processing, traditionally seen as resistant to letter transpositions. These findings suggest that bilingual orthographic processing is adaptable, with language-specific exposure reshaping letter-position encoding and enabling flexible word recognition across languages.

This longitudinal study investigates the development and interrelation of adolescent learners’ L2 English vocabulary knowledge and extramural English (EE) input. The study examines the longitudinal development of L2 English receptive vocabulary knowledge, EE input and the dynamics between L2 proficiency and EE input. Data were collected at four time points by administering vocabulary tests and questionnaires on EE activities. Generalized additive mixed models and growth curve models indicated significant vocabulary growth, particularly in the early years of secondary school, which slowed down toward the end of the study. EE activities such as gaming, social media and reading positively predicted vocabulary development, while watching television with L1 subtitles had a negative effect. Temporal network analysis revealed reciprocal relationships, suggesting that L2 proficiency influences EE input and vice versa. The findings underscore the importance of EE in L2 vocabulary development and highlight the dynamic interplay between language learning and extramural activities.

Most people are multilingual, and most multilinguals code-switch, yet the characteristics of code-switched language are not fully understood. We developed a chatbot capable of completing a Map Task with human participants using code-switched Spanish and English. In two experiments, we prompted the bot to code-switch according to different strategies, examining (1) the feasibility of such experiments for investigating bilingual language use and (2) whether participants would be sensitive to variations in discourse and grammatical patterns. Participants generally enjoyed code-switching with our bot as long as it produced predictable code-switching behavior; when code-switching was random or ungrammatical (as when producing unattested incongruent mixed-language noun phrases, such as ‘la fork’), participants enjoyed the task less and were less successful at completing it. These results underscore the potential downsides of deploying insufficiently developed multilingual language technology, while also illustrating the promise of such technology for conducting research on bilingual language use.

Older adults commonly experience declines in cognitive control, which significantly impacts their well-being. Although intensive language training, particularly interpreting, holds potential for mitigating these declines, its efficacy remains largely unexplored. Based on previous findings in the literature (especially our theoretical framework on interpreting), we designed a 24-hour programme of Between-Dialect Interpreting Training (BIT). Using a pretest-intervention-posttest design, we evaluated the efficacy of the BIT (over 8 weeks) against a control group on general cognitive ability (MoCA) and core cognitive control functions – working memory (via listening span and digit backward tasks), interference control (via Stroop and Flanker tasks) and cognitive flexibility (via colour-shape task and WCST). Results demonstrated notable between-group differences favouring the BIT, with significant improvements in listening span, Stroop effect and Stroop global RT, colour-shape switch cost and marginal improvements in digit backward score and MoCA. The implications of how language training promotes cognitive health during ageing are discussed.

This study investigated the hypothesis that 9- to 11-month-old multilingual infants learning Advanced Tongue Root (ATR) harmony languages (such as Akan) alongside other non-vowel harmony languages in Ghana (Africa) can use ATR harmony cues for speech segmentation. Using the central fixation procedure, infants were familiarized with bisyllabic words in two passages, one with ATR cues and one without, and then tested on isolated familiarized and novel bisyllabic words. Results indicate that, as a group, infants segmented words in their native language using ATR harmony cues, showing a familiarity preference. No effect of exposure to ATR harmony language(s) was found. These results provide the first evidence of word segmentation in infants learning between two and five languages, and with infants in Africa. The findings contribute to our understanding of multilingual infants’ language processing, suggesting their sensitivity to phonotactic cues for speech processing.

Individuals differ in a range of processes related to reading comprehension, including working memory capacity, decoding skills, inference making and main idea identification. In this exploratory study, we examined evoked potential N400 amplitude during reading comprehension tasks and focused on identifying the main idea in the text, modulated by working memory capacity. Participants included monolinguals or bilinguals who were either typical readers (n = 33) or had been diagnosed with dyslexia (n = 19). Analyses revealed significant group differences for main idea conditions. Participants with dyslexia showed greater N400 amplitude than typical readers, particularly in the right hemisphere, when the main idea was in the last position in the paragraph. There were no significant differences in performance between bilinguals and monolinguals, which does not support the idea of a cognitive advantage for bilingualism. It was noteworthy that, if they had dyslexia, they were similarly negatively impacted by their reading disability. Findings highlight the processing advantages typical readers have relative to dyslexia.