Bilinguals have been found to possess cognitive advantages. But the nature of this advantage is unclear. While some evidence suggests that bilinguals have developed enhanced inhibitory control abilities, other evidence suggests that they possess enhanced attentional control abilities. In the current study, English monolingual and English–Chinese bilingual young adults were tested in three non-verbal conflict tasks (Flanker task, Spatial Stroop task and Simon task). Ex-Gaussian analyses were utilized to inspect response time distributions. The two participant groups showed comparable effects of stimulus-response congruency on the Gaussian part of response distributions (μ), but different effects on the distribution tails (τ), with reduced tails for bilingual speakers particularly in the more demanding incongruent condition. These results suggest that bilingual advantage emerges from better sustained attention and attentional monitoring rather than inhibition. We also discuss the usefulness of ex-Gaussian analyses.

Much work has shown that differences in the timecourse of language processing are central to comparing native (L1) and non-native (L2) speakers. However, estimating the onset of experimental effects in timecourse data presents several statistical problems including multiple comparisons and autocorrelation. We compare several approaches to tackling these problems and illustrate them using an L1-L2 visual world eye-tracking dataset. We then present a bootstrapping procedure that allows not only estimation of an effect onset, but also of a temporal confidence interval around this divergence point. We describe how divergence points can be used to demonstrate timecourse differences between speaker groups or between experimental manipulations, two important issues in evaluating L2 processing accounts. We discuss possible extensions of the bootstrapping procedure, including determining divergence points for individual speakers and correlating them with individual factors like L2 exposure and proficiency. Data and an analysis tutorial are available at https://osf.io/exbmk/.

The current study investigates how second-language (L2) proficiency contributes to cognitive control differences among three groups of unbalanced Chinese–English bilinguals matched for socioeconomic status (SES), intelligence (IQ), education, age, culture, and L1 background. A Flanker task and the Wisconsin Card Sorting Test (WCST) were administered to measure conflict monitoring, inhibition, and mental set shifting. ANOVA analyses revealed faster performance for the High-L2 Group compared to the Low-L2 Group in the congruent, neutral, and incongruent conditions of the Flanker task. However, there were no group differences on the WCST. Multiple step-wise regression analyses showed that L2 proficiency was a predictor for the Flanker task performance in all three conditions, SES in the neutral and the incongruent condition, and IQ in the congruent condition. These results suggest that L2 proficiency, along with SES and IQ, contribute significantly to cognitive control differences in conflict monitoring among young-adult bilinguals.

This study had two purposes: (i) to see if bilingual children can differentiate their languages with respect to the ability to form compound nouns and (ii) to test the validity of previous explanations of the acquisition of compounds. Compound nouns are right-headed in English and left-headed in French. If the French–English bilingual child in this study could differentiate between the two compounding rules, his compounds should show differential order based on the language of the semantic head. The analysis was based on the child's spontaneous compound productions from 2;9 to 3;3. The results showed that the language choice of the semantic head noun predicted the order of his compounds, suggesting that he had two distinct compounding rules. The pattern of errors made by the child cannot be accounted for by any previous explanation alone. It is suggested that children use various cues to learn compound structure.

The cognate facilitation effect (i.e., a processing advantage for cognates compared to non-cognates) is an evidence of language non-selectivity in bilingual lexical access. Several studies using behavioral or electrophysiological measures have demonstrated that this effect is modulated by the degree of formal overlap between translations. However, it has never been tested with a psychophysiological measure such as pupillometry. In the present study we replicate the cognate facilitation effect by examining reaction times and pupil responses. Our results endorse pupillometry as a promising tool for bilingual research, and confirm the modulation of the cognate effect by the degree of formal similarity.

Language-specific orthography (i.e., letters or bigrams that exist in only one language) is known to facilitate language membership recognition. Yet the contribution of continuous sublexical and lexical statistics to language membership decisions during visual word processing is unknown. Here, we used pseudo-words to investigate whether continuous sublexical and lexical statistics bias explicit language decisions (Experiment 1) and language attribution during naming (Experiment 2). We also asked whether continuous statistics would have an effect in the presence of orthographic markers. Language attribution in both experiments was influenced by lexical neighborhood size differences between languages, even in presence of orthographic markers. Sublexical frequencies of occurrence affected reaction times only for unmarked pseudo-words in both experiments, with greater effects in naming. Our results indicate that bilinguals rely on continuous language-specific statistics at sublexical and lexical levels to infer language membership. Implications are discussed with respect to models of bilingual visual word recognition.

This study investigated the contribution of second-language (L2) phonetic categorization abilities and vocabulary size to the phonolexical encoding of challenging non-native phonological contrasts into the L2 lexicon. Two groups of German learners of English differing in L2 proficiency (advanced vs. intermediate) participated in an English lexical decision task including words and nonwords with /ɛ/ and /æ/ (/æ/ does not exist in German), an /ɛ/-/æ/ phonetic categorization task and an English vocabulary test. Results showed that the effects of phonetic categorization and vocabulary size on lexical decision performance were modulated by proficiency: categorization predicted /ɛ/-/æ/ nonword rejection accuracy for intermediate learners, whereas vocabulary did so for advanced learners. This suggests that sufficient phonetic identification ability is key for an accurate phonological representation of difficult L2 phones, but, for learners for whom robust phonetic identification is already in place, their ultimate success is tightly linked to their vocabulary size in the L2.

A novel combination of several experimental and non-experimental paradigms was applied to explore initial stages of incidental vocabulary acquisition (IVA) during reading in German as a second language (L2). The results show that syntactic complexity of the context positively affects incidental acquisition of new words, triggering the learner's shift of attention from the text level to the word level. A subsequent semantic priming task revealed that the new words establish associations with semantically related representations in the L2 mental lexicon after just three previous occurrences and without any consolidation period. The semantic inhibition effect for the new words (contrary to semantic facilitation for known L2 words), however, indicates that the memory traces of the new semantic representation are still very weak and that their retrieval is probably hindered by stronger semantically related representations that have much lower activation thresholds and higher potential for being selected.

This study used lexical tasks to examine associations between languages, tasks, and age in bilingual children with primary language impairment. Participants (n = 41, mean age 8;8 years) lived in the United States, spoke primarily Spanish (L1) at home and English (L2) at school, and were identified with moderate to severe impairments in both languages. A total of eight tasks (four in each language) measured breadth of vocabulary knowledge (receptive and expressive vocabulary) and aspects of lexical processing (rapid automatic naming and nonword repetition). Correlational analyses revealed older children outperformed younger children on lexical tasks in L2 but not L1, as well as relative L2 dominance for most individuals and tasks. Positive associations were found between languages on processing-based tasks but not vocabulary measures. Findings were consistent with literature on typical bilingual learners, albeit with a notable increased risk of plateau in L1 growth. Results are interpreted within a Dynamic Systems framework.

Sustained interaction between a bilingual's two languages can be a first step toward diachronic language change. We describe two investigations that explore this by examining how bilinguals process innovative syntactic structures in their first language. In the first investigation, a sentence recall/sentence matching task, bilinguals and monolinguals exhibited differences in their tolerance of expressions of induced motion, which vary in acceptability between the two languages (Portuguese and English). In the second investigation, a priming methodology was employed to induce bilinguals to produce in their first language (Spanish) innovative constructions modeled on the second language (English), using materials where the alternation is shared between the two languages (voice, reciprocal) or not (dative). The two investigations provide a window into how languages interact in bilinguals, inducing tolerance of ungrammaticality which, we will argue, could lead to long-term novel representations in the linguistic competence repositories.

This study investigates the acquisition of grammatical gender in both languages of 21 simultaneous Greek–Dutch bilingual children living in the Netherlands. Greek and Dutch stand on the two opposite sides in terms of frequency and transparency of gender cues. Consequently, monolingual acquisition of gender in Greek is precocious with few overgeneralizations of the default value, neuter, in early stages. In contrast, monolingual acquisition of gender in Dutch is very late with errors in neuter nouns persisting up to the age of 7. Simultaneous Greek–Dutch bilingual children present an interesting test case of crosslinguistic influence in the form of acceleration (Greek affecting Dutch) or delay (Dutch affecting Greek). Children were tested on gender marking on determiners and adjectives in production and grammaticality judgment tasks. Input measures of Greek and Dutch and lexical skills were also considered. Results point to crosslinguistic influence in the form of acceleration of gender discovery in Dutch.

This study examines the motion lexicon in narratives elicited from Russian–English bilinguals. Lexical choices made by the participants are compared to those made by native speakers of Russian and English in narratives elicited by the same stimuli. The analysis of bilinguals’ narratives shows that lexicalization of motion is not subject to L2 influence in these bilinguals. A few instances of L2 influence on L1 uncovered in the data are used to discuss the forms L1 attrition might take in the Russian motion lexicon.

Artificial linguistic systems can offer researchers test tube-like models of second language (L2) acquisition through which specific questions can be examined under tightly controlled conditions. This paper examines what research with artificial linguistic systems has revealed about the neural mechanisms involved in L2 grammar learning. It first considers the validity of meaningful and non-meaningful artificial linguistic systems. Then it contextualizes and synthesizes neural artificial linguistic system research related to questions about age of exposure to the L2, type of exposure, and online L2 learning mechanisms. Overall, using artificial linguistic systems seems to be an effective and productive way of developing knowledge about L2 neural processes and correlates. With further validation, artificial linguistic system paradigms may prove an important tool more generally in understanding how individuals learn new linguistic systems as they become bilingual.

Functional magnetic resonance imaging (fMRI) was used to compare brain activation from native Japanese (L1) readers reading hiragana (syllabic) and kanji (logographic) sentences, and English as a second language (L2). Kanji showed more activation than hiragana in right-hemisphere occipito-temporal lobe areas associated with visuospatial processing; hiragana, in turn, showed more activation than kanji in areas of the brain associated with phonological processing. L1 results underscore the difference in visuospatial and phonological processing demands between the systems. Reading in English as compared to either of the Japanese systems showed more activation in inferior frontal gyrus, medial frontal gyrus, and angular gyrus. The additional activation in English in these areas may have been associated with an increased cognitive demand for phonological processing and verbal working memory. More generally, L2 results suggest more effortful reading comprehension processes associated with phonological rehearsal. The study contributes to the understanding of differential brain responses to different writing systems and to reading comprehension in a second language.

This study examines the acquisition of /r/ in German and Spanish monolingual and bilingual children. German and Spanish are characterized by different /r/s. German has a uvular approximant whereas Spanish has an alveolar tap and trill. Words containing /r/ were extracted from longitudinal recordings of the children, aged 1;9 to 3;6. Results indicate that monolingual German children acquired uvular /r/ earlier than monolingual Spanish children acquired the tap and trill. The bilingual children acquired uvular /r/ similarly to the monolingual children or, in the case of /r/ clusters, they were mildly delayed. They were advanced in the acquisition of alveolar tap and they produced more /r/-like errors for the trill. Transfer patterns were observed in one child but they could not be explained by markedness or language dominance. Findings are consistent with cross-linguistic interaction in the acquisition of /r/, in which the phonological systems of the bilinguals approximate each other.

The present study examined the influence of phonology on language switching. Unlike previous studies that investigated this influence by comparing words that are phonologically similar vs. dissimilar in two languages, the current language switching study focused on the role of phonological characteristics across words. Specifically, words with the first two phonemes being identical to those of the word in the previous trial were contrasted against words without such phonological overlap. The results revealed that the switch cost asymmetry was influenced by phonological overlap. Further investigation revealed that this influence was mainly due to persisting after-effects of phonological overlap, which caused a reversal of the asymmetrical switch cost pattern in the following trial. These results clearly indicate that manipulations on the level of phonology can have an effect on language switching. Therefore, we propose that, in contrast with the claims of most models, phonological characteristics of words play an important role in language control.

Two eye-tracking experiments in the Visual World paradigm compared how monolingual Russian (Experiment 1) and heritage Russian–English bilingual (Experiment 2) listeners process contrastiveness online in Russian. Materials were color adjective–noun phrases embedded into the split-constituent construction Krasnuju položite zvezdočku . . . “Red put star . . .” whose inherent contrastiveness results from integration of multiple sources of information, i.e., word order, prosody and visual context. The results showed that while monolinguals rapidly used word order and visual context (but not contrastive prosody) to compute the contrast set even before the noun appeared in speech, heritage Russian bilinguals were very slow and took notice of multiple sources of information only when the lexical identity of the noun made the task superfluous. These results are similar to slowed processing reported in the literature for L2 learners. It is hypothesized that this slowdown in HL processing is due to cascading effects of covert competition between the two languages that starts at the level of spoken word recognition and culminates at the interfaces and, with time, it may become a major contributing force to heritage language attrition.

This study investigated the predictive effects of executive functions on bilingual language control processes. We used a flanker task, a switching task and an n-back task to investigate inhibition, shifting, and updating, respectively. We adopted a cued language switching task to investigate the language control processes during bilingual word production. Results of linear mixed effects models showed that picture naming in switch trials was significantly slower and elicited larger stimulus-locked N2 and N400-like components. The results further showed that the flanker effect alone robustly predicted the variability of the N2 but not N400-like switch effects. These findings suggest that domain-general inhibition appears to predict the intensity of inhibition exerted on the lexical items in the non-target language during bilingual word production, but bilingual language control only partially overlaps with executive functions.

The present study compared both linguistic and non-linguistic representations of motion events in Korean–English sequential bilinguals sampled at varying proficiency levels (N = 80) against each other and against those of Korean and English monolinguals (N = 15 each). The bilinguals' L2 descriptions of motion events showed that their encoding patterns were influenced by both the first language (L1) and second language (L2) and also displayed unique behaviors that were not found in either monolingual norm. The non-verbal results on a triads-matching task demonstrated that bilinguals' categorization patterns followed L1-based patterns rather than L2-based patterns. The extent to which these bilinguals employed L2 encoding patterns in their motion event descriptions was largely modulated by L2 proficiency, whereas length of immersion experience in an L2-speaking country emerged as the only predictor of their non-verbal categorization patterns. These findings suggest that the bilinguals' verbal behavior seems more susceptible to change than their non-verbal behavior.