This study examined whether L1-Mandarin learners of L2-English use verb bias and complementizer cues to process temporarily ambiguous English sentences the same way native speakers do. SVO word order places verbs early in sentences in both languages, allowing the use of verb-based knowledge to anticipate what could follow. The two languages differ, however, in whether an optional complementizer signals embedded clauses. In a self-paced reading experiment, native English speakers and L1-Mandarin learners of L2-English read sentences containing temporary ambiguity about whether a noun was the direct object of the verb preceding it or the subject of an embedded clause. Native speakers replicated previous work showing an optimally efficient interactive pattern of cue use, while non-native learners showed additive effects of the two cues, consistent with predictions of the Competition Model about learning how to use multiple cues in a second language that sometimes agree and sometimes do not.

This study examined electrophysiological correlates of sentence comprehension of native-accented and foreign-accented speech in a second language (L2), for sentences produced in a foreign accent different from that associated with the listeners' L1. Bilingual speaker-listeners process different accents in their L2 conversations, but the effects on real-time L2 sentence comprehension are unknown. Dutch–English bilinguals listened to native American-English accented sentences and foreign (and for them unfamiliarly-accented) Chinese-English accented sentences while EEG was recorded. Behavioral sentence comprehension was highly accurate for both native-accented and foreign-accented sentences. ERPs showed different patterns for L2 grammar and semantic processing of native- and foreign-accented speech. For grammar, only native-accented speech elicited an Nref. For semantics, both native- and foreign-accented speech elicited an N400 effect, but with a delayed onset across both accent conditions. These findings suggest that the way listeners comprehend native- and foreign-accented sentences in their L2 depends on their familiarity with the accent.

Text comprehension relies on high-level cognitive processes as it is the ability to revise an erroneous inference. Recent models of language processing hold that native language processing is proactive in nature (highly predictive), whereas processing seems to be weaker in the second language. However, if a prediction fails because unexpected information is encountered, reactive processing is needed to revise previous information. Twenty-four highly proficient late bilinguals were presented with narratives in L1-English and L2-Spanish. Each text demanded the revision of an initial predictive inference. Reading times and N400 amplitude suggested inferential revision is less efficient in the L2 compared to the L1. Importantly, these effects were modulated by individual differences in cognitive control and L2 proficiency. More efficient L1 comprehension was related to a balance between proactive and reactive control and lower L2 proficiency, whereas more native-like L2 comprehension was associated with a strong proactive control and higher L2 proficiency.

Assessing language in sequential bilinguals (L2 children) for the identification of language impairment suffers from lack of appropriate standardized tools and from limited understanding of the developmental trajectories of these learners. This longitudinal study compares L2 children to children with SLI in order to better understand where these groups have overlapping performance and where they differ. An analysis of standardized test scores as well as frequency of clausal embedding and morphosyntactic errors in spontaneous speech was conducted with 22 English-speaking children (aged 6;9-12;7) acquiring French as an L2 in France and 19 monolingual French-speaking children with SLI (aged 6;5–12;11). The results revealed that L2 children used clausal embedding more often than the children with SLI, but both groups had similar rates of morphosyntactic accuracy. Facility with clausal embedding from early stages of development and continuing difficulty with morphosyntactic accuracy are argued to be characteristic of typical development in L2 children.

Are simultaneous interpreters subject to the central processing bottleneck, which can postpone the reaction time and impair the performance of another concurrent task, during word production? Moreover, is there any difference between interpreters, bilinguals and monolinguals in the word production bottleneck? In this study, professional simultaneous interpreters, proficient bilinguals and monolinguals performed a dual task consisting of a picture naming task in sentence context (Task 1) and a pitch tone discrimination task (Task 2). The results show that interpreters are also subject to the central processing bottleneck during word production, and there is no significant difference between the three groups in the duration of the word production bottleneck. Unexpected differences in performance were found between English–Asian language and English–European language pairs within the interpreter group, but not within the bilingual group, showing that European-language interpreters were as fast as monolinguals in lexical access, and faster than Asian-language interpreters and bilinguals.

The current study examined whether the vocabulary skills of sequential bilingual children who learned Cantonese as a home language (L1) and English as a second language (L2) were predicted by the amount of L1 and L2 used at home. Ninety-two preschool children who learned Cantonese as L1 were recruited from a Head Start program. The amounts of L1 and L2 used at home were measured using parent questionnaires. Mixed patterns of L1 and L2 use were found across family members and home activities. After controlling for time spent in preschool, regression analyses showed that the amount of L1 and L2 used by individual family members, with the exception of older siblings, was not significantly linked to children's vocabulary skills. In contrast, the language used during some home activities such as dinner and book reading significantly predicted children's vocabulary knowledge. Implications for family involvement in facilitating children's vocabulary development are discussed.

The finding that noun production is slower and less accurate in bilinguals compared to monolinguals is well replicated, but not well understood. This study examined the two prominent theoretical accounts for this bilingual effect: weaker links and cross-language interference. Highly proficient Mandarin–English bilinguals and English-speaking monolinguals named pictures in which the effects of grammatical class, word frequency and translatability were examined. While bilinguals were slower overall than monolinguals in both L1 and L2, the magnitude of this bilingual effect was smaller for verbs than for nouns. Bilinguals showed a larger production advantage for high vs. low frequency words in their L2 relative to monolinguals and their L1. Bilinguals also showed an advantage for words with greater translatability, which did not differ across grammatical categories. The findings lend partial support to the weaker links account, and reveal cross-language facilitation rather than interference.

In two experiments with Telugu–English bilinguals, we examined if bilingual speakers are sensitive towards an interlocutor's (cartoon) relative language proficiency when they voluntarily selected a language for object naming. After familiarization with four different cartoons with varied L2 proficiency, participants did a voluntary naming task. In Experiment 1, participants explicitly indicated their choice of language before naming objects. In Experiment 2, participants named the objects directly. In both experiments, language choices and switchrates were thoroughly modulated by the participants’ perceived linguistic ability of the cartoon. However, awareness of perceived proficiency of the cartoons did not modulate naming latency. These results provide strong support for the adaptive control hypothesis, showing that bilingual speakers are sensitive to their interlocutor's language needs and this influences how they plan their language use. The results provide evidence of speakers taking into consideration the language proficiency of interlocutors, suggesting extreme adaptability of the bilingual mind.

Bilingualism imposes costs to language processing but benefits to word learning. We test a new hypothesis that relates costs in language processing at study to benefits in learning at test as desirable difficulties. While previous studies have taught vocabulary via bilinguals’ native language (L1), recent evidence suggests that bilinguals acquire regulatory skill in the L1 to coordinate the use of each language. We hypothesized that L1 regulation underlies the observed costs and benefits, with word learning advantages depending on learning via the L1. Four groups learned novel Dutch words via English translations: English monolinguals, and English–Spanish, Spanish–English, and Chinese–English bilinguals. Only English–Spanish bilinguals demonstrated a word learning advantage, but they adopted a costly study strategy compared to monolinguals. The results suggest that bilingual advantages in vocabulary learning depend on learning via the L1 or dominant language because learning via the L1 allows bilinguals to engage regulatory skills that benefit learning.

Determining bilingual status has been complicated by varying interpretations of what it means to be bilingual and how to quantify bilingual experience. We examined multiple indices of language dominance (self-reported proficiency, self-reported exposure, expressive language knowledge, receptive language knowledge, and a hybrid), and whether these profiles related to performance on linguistic and cognitive tasks. Participants were administered receptive and expressive vocabulary tasks in English and Spanish, and a nonlinguistic spatial Stroop task. Analyses revealed a relation between dominance profiles and cognate and nonlinguistic Stroop effects, with somewhat different patterns emerging across measures of language dominance and variable type (continuous, categorical). Only a hybrid definition of language dominance accounted for cognate effects in the dominant language, as well as nonlinguistic spatial Stroop effects. Findings suggest that nuanced effects, such as cross-linguistic cognate effects in a dominant language and cognitive control abilities, may be particularly sensitive to operational definitions of language status.

Listening to speech entails adapting to vast amounts of variability in the signal. The present study examined the relationship between flexibility for adaptation in a second language (L2) and robustness of L2 phonolexical representations. Phonolexical encoding and phonetic flexibility for German learners of English were assessed by means of a lexical decision task containing nonwords with sound substitutions and a distributional learning task, respectively. Performance was analyzed for an easy (/i/-/ɪ/) and a difficult contrast (/ε/-/æ/, where /æ/ does not exist in German). Results showed that for /i/-/ɪ/ listeners were quite accurate in lexical decision, and distributional learning consistently triggered shifts in categorization. For /ε/-/æ/, lexical decision performance was poor but individual participants’ scores related to performance in distributional learning: the better learners were in their lexical decision, the smaller their categorization shift. This suggests that, for difficult L2 contrasts, rigidity at the phonetic level relates to better lexical performance.

Spanish speakers tend to perceive an illusory [e] preceding word-initial [s]-consonant sequences, e.g., perceiving [stið] as [estið] (Cuetos, Hallé, Domínguez & Segui, 2011), but this illusion is weaker for Spanish speakers who know English, which lacks the illusion (Carlson, Goldrick, Blasingame & Fink, 2016). The present study aimed to shed light on why this occurs by assessing how a brief interval spent using English impacts performance in Spanish auditory discrimination and lexical decision. Late Spanish–English bilinguals’ pattern of responses largely matched that of monolinguals, but their response times revealed significant differences between monolinguals and bilinguals, and between bilinguals who had just completed tasks in English vs. Spanish. These results suggest that late bilinguals do not simply learn to perceive initial [s]-consonant sequences veridically, but that elements of both their phonotactic systems interact dynamically during speech perception, as listeners work to identify what it was they just heard.

The current study examines the role of cognitive and perceptual individual differences (i.e., aptitude) in second language (L2) pronunciation learning, when L2 learners’ varied experience background is controlled for. A total of 48 Chinese learners of English in the UK were assessed for their sensitivity to segmental and suprasegmental aspects of speech on explicit and implicit modes via behavioural (language/music aptitude tests) and neurophysiological (electroencephalography) measures. Subsequently, the participants’ aptitude profiles were compared to the segmental and suprasegmental dimensions of their L2 pronunciation proficiency analyzed through rater judgements and acoustic measurements. According to the results, the participants’ segmental attainment was associated not only with explicit aptitude (phonemic coding), but also with implicit aptitude (enhanced neural encoding of spectral peaks). Whereas the participants’ suprasegmental attainment was linked to explicit aptitude (rhythmic imagery) to some degree, it was primarily influenced by the quality and quantity of their most recent L2 learning experience.

Word-initial obstruent-liquid clusters, frequent in English (e.g., blue), are prohibited in Korean. Korean learners of English perceptually repair illicit word-initial consonant sequences with an epenthetic vowel [ʊ]. Thus they might perceive blue as b[ʊ]lue, and, at least initially, also represent it lexically as a disyllabic word. We ask whether the sound sequences permitted in one's L1 influence the way L2 words are represented in the mental lexicon. If they do, we predict that in a lexical decision task, Korean learners will accept nonwords containing epenthetic vowels ([bʊˈluː] for blue) as real English words more often than English listeners. These predictions were confirmed: we observed high error rates on test nonwords ([bʊˈluː]) by the Korean participants only, accompanied by few errors on control nonwords ([bɪˈluː]), suggesting that learners’ lexical representations for familiar L2 words can be activated by nonwords that obey their L1 phonotactic grammar.

Learning and using additional languages can result in structural changes in the brain. However, the time course of these changes, as well as the factors the predict them, are still not well understood. In this longitudinal study we test the effects of bilingual immersion on brain structure of adult sequential bilinguals not undergoing any language training, who were scanned twice, three years apart. We observed significant increases in grey matter volume in the lower left cerebellum, mean white matter diffusivity in the frontal cortex, and reshaping of the left caudate nucleus and amygdala and bilateral hippocampus. Moreover, both prior length of immersion and L2 age of acquisition were significant predictors of volumetric change in the cerebellum. Taken together, these results indicate that bilingualism-induced neurological changes continue to take place across the lifespan and are strongly related to the quantity and quality of bilingual immersion, even in highly-immersed adult bilingual populations.

The question of whether bilingualism conveys a broader advantage in executive functions has recently been controversially discussed, with the empirical findings presenting a complex pattern of positive and null results. Here we present results from three standard tasks measuring executive functions (Flanker; Simon; Spatial Stroop) in which we compared performance of English monolingual to Chinese–English bilingual young adults. Participants provided responses via movement of a computer mouse rather than the conventional key presses, which provides a rich signal of the unfolding response dynamics. Clear differences between bi- and monolinguals emerged, with the former providing more ‘efficient’ responses than the latter. Results are discussed regarding the extent to which these results can be characterised as a genuine “bilingual advantage”.

The anterior cingulate cortex (ACC) and the dorsolateral prefrontal cortex (DLPFC) are involved in conflict detection and conflict resolution, respectively. Here, we investigate how lifelong bilingualism induces neuroplasticity to these structures by employing a novel analysis of behavioural performance. We correlated grey matter volume (GMV) in seniors reported by Abutalebi et al. (2015) with behavioral Flanker task performance fitted using the diffusion model (Ratcliff, 1978). As predicted, we observed significant correlations between GMV in the DLPFC and Flanker performance. However, for monolinguals the non-decision time parameter was significantly correlated with GMV in the left DLPFC, whereas for bilinguals the correlation was significant in the right DLPFC. We also found a significant correlation between age and GMV in left DLPFC and the non-decision time parameter for the conflict effect for monolinguals only.

We submit that this is due to cumulative demands on cognitive control over a lifetime of bilingual language processing.

The relationship between multilingualism and tolerance of ambiguity (TA) has been examined in recent studies (e.g., Dewaele & Li, 2013; van Compernolle, 2016), which focus upon multilinguals with mixed nationalities in non-EFL contexts. Most of these studies regrettably reflect a failure to use effect sizes or provide information on the reliability and validity of the instruments used. The present study explored the relationship between multilingualism and TA by focusing upon 260 English-using multilinguals of one single nationality in an EFL context. Factor analysis revealed a three-factor solution, rather than a four-factor solution of the original TA scale, suggesting a need to re-examine the validity of such instruments when used outside of their native contexts. The results identified multilingualism, number of languages known and gender as important predictors for TA. Given the relative nature of effect-size benchmarks, a topic-specific effect-size benchmark system is proposed to (re-)interpret the present and previous findings.