This study investigates second language (L2) phonetic categorization and phonological encoding of L2 words (hereafter, phonolexical encoding1) with phonemic and allophonic cross-linguistic mismatches. We focus on the acquisition of Spanish /ɾ/-/l/ and /ɾ/-/t/ contrasts among Spanish learners with American English (AE) and Mandarin Chinese (hereafter, Chinese) as first languages (L1s). [ɾ] and [t] are positional allophones in AE but separate phonemes in Spanish. The phoneme /ɾ/ is absent in Chinese. AE learners showed nativelike phonetic categorization and little between-contrast difference in phonolexical encoding, suggesting that L1 positional allophony does not necessarily impede L2 contrast acquisition. Chinese learners showed persistent perceptual difficulties with both contrasts due to perceptual similarity. Phonetic categorization significantly predicted phonolexical encoding for /ɾ/-/t/ contrasts for Chinese learners bidirectionally, while AE learners showed this relationship only when /t/ was incorrectly replaced by /ɾ/ in Spanish words. This asymmetry can be driven by the fact that [t] is the dominant allophone of /t/ in AE, while [ɾ] is a positional allophone. It suggests L1 allophonic knowledge heightens perceptual monitoring when evaluating substitutions that conflict with L1 phonological expectations. This study calls for more nuanced treatment of L1 influence in L2 phonological acquisition models, especially at the allophonic level.

The present study compares the use of morphological case for argument interpretation between German L1 speakers in Norway and Germany to investigate whether and how processing may be affected by attrition. Participants were presented with a spoken sentence and pictures of two scenes, one showing an event as described by a transitive or ditransitive sentence and another showing the same event, with the roles of agent and patient (transitives) or recipient and theme (ditransitives) reversed. Their task was to select the scene that matched the sentence. End-of-sentence responses show no between-group differences in comprehension. Moreover, eye movements show that both groups exploit case marking on the first noun phrase in transitive sentences in the same way. However, differences in processing between groups emerge for the use of case marking on the first object following a ditransitive verb. While the home country group shows a higher likelihood of looks to the target after a dative-marked article than after an accusative-marked article prior to the second object, the reverse holds for the expat group, at least temporarily. Altogether, the results indicate subtle changes in the processing of alternating argument orders in ditransitive sentences in L1 German, potentially as a result of the bi-/multilingual experience.

To examine cross-linguistic influences during bilingual lexical processing, a word type frequently used is cognates (i.e., translation equivalents with an overlap in form and meaning, such as English-German tomato-Tomate). Cognates have been found to be processed faster and more accurately than translation equivalents without such overlap (i.e., noncognates, such as English-German potato-Kartoffel). This cognate facilitation effect (CFE) is considered evidence for language co-activation in bilinguals and has been studied mostly in children and adults. The aim of the current study was to examine this effect in a more heterogeneous group of adolescent L2 learners and explore its potential modulation by L2 proficiency and stimulus frequency. For this purpose, 68 L1 German low-intermediate learners of L2 English participated in an English lexical decision task on cognate and noncognate words. Notably, CFEs could not be replicated in this group of learners. However, further analysis revealed that word recognition was modulated by both participants’ L2 English proficiency and target word frequency. The results of the present study add to the literature on modulating factors of the CFE, expand them to a population of early second language learners, and underline the need for future research on factors influencing cross-linguistic activation.

This longitudinal study examined the impact of L2 acquisition on the narrative development of L1-Turkish dominant children who were exposed to L2-English immersion compared to their peers who were not exposed to L2-English immersion but to L1-Turkish. The study involved 155 children, aged 5, 7, and 9 at Time 1, assessing their narrative production, linguistic complexity, and narrative comprehension over a one-year period. Children who were exposed to L2-English immersion received intensive L2-English instruction from a young age while living in an L1-Turkish dominant society. For both time points, L2-English immersion children performed better than L1-Turkish dominant children for L1 narrative production. While no overall group differences emerged in linguistic complexity, L2-English immersion children exhibited higher complexity in L1 relative to their L2 for both time points, suggesting a facilitative effect of early L2 exposure on L1 narrative structure. These findings support the idea that bilingualism may foster narrative skills. These results highlight the importance of early bilingual education, especially when both languages are equally supported, contributing to children’s overall language development.

Variability in the second language (L2) referential choice could be due to lower language proficiency in the L2 or cross-linguistic influence. We compare the L2 English referential choices of bilinguals of typologically different languages (Spanish and English, null subject and non-null subject) to those of bilinguals of typologically similar languages (Dutch and English, both non-null subject and both using pronouns similarly in the target context). Bilinguals’ performance was further compared to that of a group of functional monolingual English speakers. Both bilingual groups were highly proficient, to explore whether high proficiency would attenuate differences with monolinguals. Participants completed a picture-description task eliciting references to antecedents in two-character contexts. Performance was comparable among all three groups in all conditions—evidence that cross-linguistic influence did not play a role for bilingual referential choices. These results thus show that highly proficient bilinguals of both typologically different and similar languages can perform comparably to monolinguals.

The importance of additional language learning (ALL) is on the rise, but we do not yet have a full understanding of how learners with different characteristics approach this task. Here, we discuss the potential impact of attention-deficit/hyperactivity disorder (ADHD), a prevalent learning disability, on classroom ALL. Learners with ADHD show difficulties in the attention networks of sustained attention and executive control. It is critical, therefore, to ask how these difficulties of learners with ADHD might manifest in the demanding task of ALL, but to date there is very limited research examining this issue. The current paper sets out a theoretical framework for examining ALL in learners with ADHD, reviews the extant literature, and most importantly calls for future research to examine the way in which learners with ADHD manage the process of ALL, in an effort to highlight the involvement of sustained attention and executive control in ALL more generally.

This study investigates the production, online processing, and offline comprehension of non-canonical structures in Mandarin-speaking children with Developmental Language Disorder (DLD). We tested three Mandarin non-canonical structures, which differed in word order, the presence or absence of morphosyntactic cues, and the distance between the displaced element and its trace. Syntactic priming was adopted to elicit production, and a self-paced listening task with picture verification was used to examine online processing and offline comprehension accuracy, among 22 DLD children aged 5 to 9 and 37 age-, SES-, and nonverbal IQ-matched typically developing (TD) children. Results showed a quantitative difference between DLD and TD children across non-canonical structures in production and offline comprehension. In online processing, TD children immediately used different cues when they were available, whereas DLD children relied on the most informative cue within a given structure and context and integrated redundant cues only at a later stage. These findings point toward a complex interaction of representational weakness and domain-general processing constraints whereby DLD children show difficulties in allocating processing resources to integrate multiple linguistic cues.

Continuous speech presents a challenge to the ab initio learner, as the language-specific segmentation strategies they use in their first language are not always reliable cues in other languages (Cutler 2001 International Journal of Research and Practice in Interpreting, 5(1), 1–23). Yet, they are able to use more general acoustic, prosodic, and statistical cues to word boundaries, as well as lexical similarity to their first language (e.g., Shoemaker & Rast 2013. Second Language Research, 29(2), 165–183) to recognize words at first exposure to a new language. In the current study, we investigated whether adult ab initio learners’ ability to recognize words after brief exposure to continuous speech in a new language is improved when that speech is produced using an infant-directed register, a style of speech found to facilitate segmentation in infancy (Thiessen et al. 2005. Infancy 7(1), 53–71). In a series of experiments, we demonstrate that although English ab initio learners of German benefited from infant-directed speech, their performance was generally lower than in previous studies unless task demands were reduced. These learners also benefited from word length and from frequency of occurrence, as has been shown previously, but these did not interact with register. As in infancy, learner-directed speech registers appear to facilitate initial processing and recognition in adult ab initio learners.

Being literate likely has consequences for learning a second language, but surprisingly little research has been devoted to how emergent literacy affects second-language acquisition processes. Using a word learning experiment, we aimed to tease apart two possible ways through which literacy could impact second-language acquisition: through literacy-induced restructuring and through using written input in addition to spoken input. Totally, 166 (L1 Arabic and L2 Dutch) participants of varying literacy levels (emergent readers and more experienced readers) had to acquire eight words as names of people and pet animals, of which some only varied in one phoneme. Half of the participants received only auditory input to learn these names, and the other half also received written input. Bayesian mixed-effects models indicate that experienced readers are better able to acquire words and a phonological contrast than emergent readers, pointing toward a benefit from literacy-induced restructured linguistic representations. We also obtained anecdotal evidence that, although experienced readers seemingly benefit more from written input than emergent readers, the latter group could still use written input to a small extent. Possibly, written input might be beneficial, even though it cannot be properly decoded yet—at the very least it does not harm providing such input.

As people increasingly interact with large language models (LLMs), a critical question emerges: do humans process language differently when communicating with an LLM versus another human? While there is good evidence that people adapt comprehension based on their expectations toward their interlocutor in human–human interaction, human–computer interaction research suggests the adaptation to machines is often suspended until expectation violation occurs. We conducted two event-related potential experiments examining Chinese sentence comprehension, measuring neural responses to semantic and syntactic anomalies attributed to an LLM or a human. Experiment 1 revealed reduced N400 but larger P600 responses to semantic anomalies in LLM-attributed text than human-attributed one, suggesting participants anticipated semantic errors yet required increased composition/integration efforts. Experiment 2 showed enhanced P600 responses to LLM-attributed than human-attributed syntactic anomalies, reflecting greater reanalysis or integration difficulty in the former than in the latter. Notably, neural responses to LLM-attributed semantic anomalies (but not syntactic anomalies) were further modulated by participants’ belief about humanlike knowledge in LLMs, with a larger N400 and a smaller P600 in participants with stronger belief of humanlike knowledge in LLMs. These findings provide the first neurocognitive evidence that people develop mental models of LLM capabilities and adapt neural processing accordingly, offering theoretical insights aligned with multidisciplinary frameworks and practical implications for designing effective human–AI communication systems.

This study investigates how practice conditions—specifically spacing and contextual variation—affect incidental vocabulary learning during second language reading. While repeated encounters with unfamiliar words support lexical acquisition, it remains unclear how the distribution of exposures and consistency of surrounding contexts modulate this process. Ninety-two Catalan/Spanish bilingual learners of English read texts of approximately 900 words containing 20 pseudowords, which served as novel vocabulary items, under two conditions: three readings of the same text or one reading of three different texts. Each target pseudoword appeared six times across the three readings. Repeated reading was either massed (one session) or spaced over three weekly sessions. Eye movements were recorded to assess online processing of target pseudowords. Results showed that spaced and contextually varied conditions elicited more and longer fixations, indicating increased processing demands. These more difficult conditions were not desirable as they did not facilitate recall or recognition of new vocabulary. Instead, immediate vocabulary gains were greater in the massed condition, which was less cognitively demanding during reading, though these gains declined more sharply. The findings suggest that the effectiveness of practice conditions depends on how well they support processing of previously encountered novel words at an optimal level of difficulty.