This review provides an update on what we know about differences in prediction in a first and second language after several years of extensive research. It shows when L1/L2 differences are most likely to occur and provides an explanation as to why they occur. For example, L2 speakers may capitalize more on semantic information for prediction than L1 speakers, or possibly they do not make predictions due to differences in the weighting of cues. A different weighting of cues can be the result of prior experience from the L1 and/or the prior experience in an experiment which affects L1 and L2 processing to a different extent. Overall, prediction in L2 processing often emerges later and/or is weaker than in L1 processing. Because L2 processing is generally slower, L1/L2 differences are likely to occur at certain levels of prediction, most notably at the form level, in line with a prediction-by-production mechanism.

Language control in bilinguals is often investigated with the language switching paradigm. Switch costs reflect the ease/difficulty of applying this control mechanism. The type of stimuli employed in the experiments may influence switch costs. To date, only one study has compared digit vs picture processing, reporting reduced switch costs for digits (Declerck, Koch & Philipp, 2012). This result was adjudicated to phonological overlap between the languages used. Crucially, it remains an open question whether this digit effect generalises to language combinations without phonological relation. We fill this gap by investigating language switching with two language pairs differing in relative proficiency (L1 Chinese–L2 English, L1 Chinese–L3 French), where cross-language phonological activation is not expected. Overall, a digit effect is observed in the Chinese–English pair. Contrary to Declerck et al.'s (2012) finding, digits increased switch costs. Phonological mediation cannot explain this effect; instead, we suggest its origin lies in within-language word association links.

In “The Devil's Dictionary”, Bierce (1911) defined language as “The music with which we charm the serpents guarding another's treasure.” This satirical definition reflects a core truth – humans communicate using language to accomplish social goals. In this Keynote, we urge cognitive scientists and neuroscientists to more fully embrace sociolinguistic and sociocultural experiences as part of their theoretical and empirical purview. To this end, we review theoretical antecedents of such approaches, and offer a new framework – the Systems Framework of Bilingualism – that we hope will be useful in this regard. We conclude with new questions to nudge our discipline towards a more nuanced, inclusive, and socially-informed scientific understanding of multilingual experience. We hope to engage a wide array of researchers united under the broad umbrella of multilingualism (e.g., researchers in neurocognition, sociolinguistics, and applied scientists).

Learning a new language is an important goal that many individuals find difficult to achieve, particularly during adulthood. Several factors have related this variability to different extrinsic (learning condition, difficulty of the materials) and intrinsic (cognitive abilities) factors, but the interaction between them is barely known. In two experiments, participants learned English grammar rules in intentional (Experiment 1) or explicit (Experiment 2), and incidental learning-contexts. Overall, results of this study indicated that intentional-explicit conditions benefitted rule-learning, as compared to incidental conditions. This benefit was mainly present when participants were learning an easy-rule; explicit and incidental learning did not differ in the case of participants learning a difficult rule (Experiment 2). Moreover, individual differences in executive functioning predicted successful learning in interaction with difficulty. When learning an easy-rule, proactive control facilitated intentional learning. In contrast, when participants were learning a complex-rule, incidental learning was enhanced by lower involvement of proactive control.

English is imposed as the language of instruction in multiple linguistically diverse societies where there is more than one official language. This might have negative educational consequences for people whose first language (L1) is not English. To investigate this, 47 South Africans with advanced English proficiency but different L1s (L1-English vs. L1-Zulu) were evaluated in their listening comprehension ability. Specifically, participants listened to narrative texts in English which prompted an initial inference followed by a sentence containing an expected inference or an unexpected but plausible concept, assessing comprehension monitoring. A final question containing congruent or incongruent information in relation to the text information followed, assessing the revision process. L1-English participants were more efficient at monitoring and revising their listening comprehension. Furthermore, individual differences in inhibitory control were associated with differences in revision. Results show that participants’ L1 appears to supersede their advanced English proficiency on highly complex listening comprehension.

The present study investigated lexical production and innovation of 202 participants across six groups: child and adult heritage speakers of Russian, dominant in Hebrew or American English, and monolingual Russian-speaking children and adults. Understanding quantitative performance across these six groups was intended to provide a comprehensive perspective on heritage language (HL) development, while comparing the participants’ qualitative non-target response patterns would elucidate the organization of the HL lexicon. We assessed the production of Russian nouns and verbs using a naming task. We then considered the effects of input at the societal and lexical levels (focusing on word frequency and age of acquisition). Our findings are discussed in terms of accounts of HL developmental trajectories: monolingual-like trajectory, frozen lexical development, attrition, and new language variety in a contact situation. The results presented no evidence for attrition, while elements of the other three trajectories were found in our quantitative and qualitative analyses.

Many cross-language sentence processing studies showed structural priming, which suggests a shared representation across languages or separate but interacting representations for each language. To investigate whether multilinguals can rely on such representations to predict structure in comprehension, we conducted two visual-world eye-tracking priming experiments with Cantonese–Mandarin-English multilinguals. Participants were instructed to read aloud prime sentences in either Cantonese, Mandarin, or English; then they heard a target sentence in Mandarin while looking at the corresponding target picture. When prime and target had different verbs, there was within-language structural priming only (Mandarin-to-Mandarin, Experiment 1). But when prime and target had translation-equivalent verbs, there was not only within-language but also between-language priming (only Cantonese-to-Mandarin, Experiment 2). These results indicate that structure prediction between languages in comprehension is partly lexically-based, so that cross-linguistic structural priming only occurs with cognate verbs.

Previous studies analysing the differences in emotionality in first and second language suggest that affective content of lexical items is modulated in certain contexts. This paper investigates the differences in valence and arousal ratings for 300 early words, in both oral and written modalities, through speakers’ subjective appraisal of words given by two immersion groups of Spanish late bilinguals (Chinese and European) compared with a group of native speakers. The main goal of our study is to identify the lexical areas where variability occurs, regarding to a set of affective (emotional charge and intensity), grammatical (nouns, adjectives and verbs) and semantic (concreteness) features of words. Our results show that valence is the dimension where the greatest variability is observed between native and bilinguals, although the influence of the independent factors differs considerably. Besides, arousal yields illuminating data regarding the grammatical category of words and differentiation between the groups of participants.

Words’ morphemic structure and their orthographic representations vary across languages. How do bilingual experiences with structurally distinct languages influence children's morphological processes for word reading? Focusing on English literacy in monolinguals and bilinguals (N = 350, ages 5–9), we first revealed unique contributions of derivational (friend-li-est) and compound (girl-friend) morphology to early word reading. We then examined mechanisms of bilingual transfer in matched samples of Spanish–English and Chinese–English dual first language learners. Results revealed a principled cross-linguistic interaction between language group (Spanish vs. Chinese bilinguals) and type of morphological awareness. Specifically, bilinguals’ proficiency with the type of morphology that was less characteristic of their home language explained greater variance in their English literacy. These findings showcase the powerful effects of bilingualism on word reading processes in children who have similar reading proficiency but different language experiences, thereby advancing theoretical perspectives on literacy across diverse learners.

Are bilingual speakers’ representations of pronominal expressions completely independent in the two languages, or is there sharing of discourse-level representations cross-linguistically? In the present study, we address this question by using a sentence comprehension task that implements the cross-linguistic priming technique at the discourse-level.

In two experiments conducted with Spanish–English bilinguals, we prime dis-preferred interpretations for ambiguous pronouns in the second language (English) by using first language (Spanish) pronoun interpretation primes. In experiment 1, Spanish null pronouns prime second-mentioned/object interpretations in English, showing an effect of priming. In experiment 2, Spanish explicit pronouns prime second-mentioned/object interpretations in English, indicating that an effect of priming approaches significance.

The results demonstrate that bilinguals’ inferences about probability distributions and coherence relations are susceptible to cross-linguistic influence. The strength of the priming effect is discussed within models of cross-language abstract representations.

To date, the evidence regarding the effect of bilingualism/multilingualism on short-term memory (STM) and working memory (WM) capacity is inconclusive. This study investigates whether multilingualism has a positive effect on the verbal STM and WM capacity of neurotypical middle-aged and older individuals. Eighty-two L1-Norwegian sequential bilingual/multilingual academics were tested with tasks measuring verbal STM/WM capacity. Degree of bilingualism/multilingualism for each participant was estimated based on a comprehensive questionnaire. Different measures of bilingualism/multilingualism were used. Data on potentially influencing non-linguistic factors were also collected. Correlation and regression analyses showed that multilingualism impacts both verbal STM and verbal WM. In particular, all analyses showed that number of known foreign languages was the strongest predictor of verbal STM and WM capacity. The results are discussed in light of recent studies on the impact of bilingualism on STM/WM and on recent proposals regarding the mechanism underlying so-called bilingual advantage.

This study investigates the phonetic outcome of mixed-language speech in Bengali and Indian English, towards understanding cross-language interaction in highly proficient bilinguals. We compare spectral properties of L2 vowels [æ] (common to L1, L2) and [ʌ] (absent in L1) in code-switched (mixed) vs. nonswitched productions. Results reveal asymmetrical shifts in both vowels during mixed productions, towards related L1 categories. We interpret this as a temporary increase in cross-language phonetic interaction during mixed-language use, leading to a shift towards L1 norms, evidencing transfer effects on L2 vowels. We elicit mixed productions through two tasks: cued picture-naming and code-switching, to assess if experimental paradigm independently influences the behavior under study. Results reveal parallel patterns, but small magnitude differences, across paradigms. We discuss these findings in light of recent proposals about asymmetries in short-term phonetic interaction, postulated discursive factors in code-switching, and the issue of comparability between paradigms in transfer studies.

Code-switching is generally dispreferred at points of non-shared word order across a bilingual's two languages. In priming studies, this dispreference persists even following exposure to a code-switched non-shared-word-order utterance. The present study delves deeper into the scope of code-switching priming by investigating whether lexical repetition across target and prime, a factor known to boost structural priming, can increase code-switching at points of word order divergence. Afrikaans–English bilinguals (n=46) heard prime sentences in which word order, lexical repetition, and switch position were manipulated and subsequently produced code-switched picture descriptions. The results show that lexical repetition boosts the priming of code-switching in a non-shared word order. The findings demonstrate that code-switching in production is affected by a dynamic interplay between factors both language-internal (i.e., word order) and language-external (i.e., priming, and specifically lexical repetition).

A large literature has shown that language context –mixing and switching between languages – impacts lexical access processes during bilingual speech production. Recent work has suggested parallel contextual effects of language context on the phonetic realization of speech sounds, consistent with interactions between lexical access and phonetic processes. In this pre-registered study, we directly examine the link between lexical access and phonetic processes in Spanish–English bilinguals using picture naming. Using automated acoustic analysis, we simultaneously gather measures of reaction time (indexing lexical access) and acoustic properties of the initial consonant and vowel (indexing phonetic processes) for the same speakers on the same trials. Across measures, we find consistent, robust effects of mixing and language dominance. In contrast, while switching effects are robust in reaction time measures, they are not detected in phonetic measures. These inconsistent effects suggest there are constraints on the degree of interaction between lexical access and phonetic processes.

Earlier acquisition of English is associated with better academic performance for dual language learners (DLLs), but large-scale, prospective, longitudinal studies examining how trajectories for English acquisition relate to school-based outcomes, accounting for relevant covariates, are rare. We explored how the grade in which DLLs (N = 17,548; 47% female; 80% free/reduced-price lunch; 86% Latino, 10% Black, and 4% White/Other) acquire English proficiency, defined by the school district, relates to academic outcomes (grade retention, GPA, reading and math test scores) in 5th grade, controlling for gender, ethnicity, poverty, and school readiness skills at age 4. Earlier acquisition of English, especially before 2nd grade, predicted better performance on each 5th grade outcome. Earlier proficiency in English was even more important for 5th grade outcomes for those with initially high cognitive skills, Latino/Hispanic DLLs (compared to Black DLLs), and those not in poverty. Implications for practice and research are discussed.

A growing body of research suggests that bilingualism may afford benefits to certain aspects of cognitive functioning. Inconsistent findings may arise because of methodological differences within and across studies. One limitation is that studies often compare linguistically similar languages. The present study recorded brain activity (event-related potentials; ERPs) while English monolinguals, English–French bilinguals, and Arabic–English bilinguals completed an n-back task and a delayed matching-to-sample task. Group ERP differences were observed in the absence of behavioral differences. In the delayed matching-to-sample task, monolinguals exhibited smaller N2 amplitude compared to both bilingual groups, and smaller P3b amplitude compared to English–French bilinguals. In the n-back, English–French bilinguals displayed larger P3b amplitudes than monolinguals and Arabic–English bilinguals. P3b amplitude did not differ between Arabic–English bilinguals and monolinguals in either task. These results suggest that conflicting findings across studies may be due in part to the linguistic distance between the languages under study.

Language production is incremental in nature; we tend to plan linguistic chunks prior to articulating the first word of the utterance. Researchers have acquired knowledge about how far ahead sentences are generally planned, but mostly in monolinguals or the speaker's first language (Allum & Wheeldon, 2007; Martin, Crowther, Knight, Tamborello II, & Yang, 2010; Wagner, Jescheniak, & Schriefers, 2010). It is unclear whether the scope of planning is the same in bilinguals, or the speaker's second language. Here, we examined planning scope in Dutch–English bilinguals' sentence production using a paradigm that elicits descriptions of short animations. Analyses of speech onset times and articulation durations suggest that, on the surface, bilinguals have comparable planning scope in L1 and L2. However, in their L2, bilinguals extended their articulation duration, suggesting that they committed early to the initial noun phrase, but produced it more slowly to buy time to plan the next noun phrase.