Substantial research suggests that high variability (multitalker) phonetic training helps second language (L2) adults improve differentiation of challenging nonnative speech sounds. Is such training also useful for L2 children? Existing studies have mixed findings and important limitations. We investigate the potential benefits of computerized…

In this study, we investigated the learning of indexical features by English-speaking adults using a novel experimental paradigm. In a conceptual replication of Rácz, Hay, and Pierrehumbert (2017), participants learned an allomorphy pattern cued by a given social context. The social contexts were represented by conversation partners who differed…

The Less-Is-More hypothesis was proposed to explain age-of-acquisition effects in first language (L1) and second language (L2) learning. We scrutinize different renditions of the hypothesis by examining how learning outcomes are affected by (a) limited cognitive capacity, (b) reduced interference resulting from less prior knowledge, and (c)…

This meta-analysis aimed to clarify the complex relationship between repetition and second language (L2) incidental vocabulary learning by meta-analyzing primary studies reporting correlation coefficients between the number of encounters and vocabulary learning. We synthesized and quantitatively analyzed 45 effect sizes from 26 studies (N = 1,918)…

This study aimed to investigate which word-related variables play a role in Dutch-speaking children's L2 word learning through out-of-school exposure prior to classroom instruction in the foreign language. We used different measures to investigate the role of frequency, concreteness, cognateness, and age of acquisition (AoA) in receptive…

We investigated the potential influence of implicit learning mechanisms on L2 morphosyntactic attainment by examining the relationship between age of onset (AoO), two cognitive abilities hypothesized to underlie implicit learning (phonological short-term memory and implicit statistical learning), and performance on an auditory grammaticality…

A central question in multilingualism research is how multiple languages interact. Most studies have focused on first (L1) and second language (L2) effects on a third language (L3), but a small number of studies dedicated to the opposite transfer direction have suggested stronger L3 influence on L2 than on L1 in postpuberty learners. In our study,…

We meta-analyzed the effectiveness of incidental second language word learning from spoken input. Our sample contained 105 effect sizes from 32 primary studies employing meaning-focused word-learning activities with 1,964 participants with typical cognitive functioning. The random-effects meta-analysis yielded a mean effect size of g = 1.05,…

This study examined the crosslinguistic sharing of morphological awareness (MA) in biliteracy development. The analysis included 34 correlational studies with 41 independent samples (N = 4,104). Correlational coefficients were meta-analyzed, yielding four main findings: (a) the correlation between first language (L1) and second language (L2) MA…

To probably overcome the challenge of learning two languages at the same time, infants raised in a bilingual environment pay more attention to the mouth of talking faces than same-age monolinguals. Here we examined the consequences of such preference for monolingual and bilingual infants' ability to perceive nonspeech information coming from the…

Many connectives, such as "therefore" and "however," are used very frequently in the written modality. Their acquisition thus represents an important milestone in developing written language competences. In this article, we assess the development of competence with such connectives by native French speakers in a sentence-level…

Montrul's (2008) onset age hypothesis predicts that, if attrition occurs in early bilingualism, it will be more severe in simultaneous than in sequential bilinguals. This study tested that prediction in an eye-tracking experiment focused on the processing of Spanish gender agreement during sentence reading. Heritage Spanish speakers exposed to…

Factors influencing native and nonnative signers' syntactic judgment ability in American Sign Language (ASL) were explored for 421 deaf students aged 7;6-18;5. Predictors for syntactic knowledge were chronological age, age of entering a school for the deaf, gender, and additional learning disabilities. Mixed-effects linear modeling analysis…

An enduring question is whether language learning aptitude is a stable trait or is one influenced by experience, such as living with two languages. We investigated aptitude in bilinguals and treated their bilingual experience as an aggregate of variables, focusing on how individual differences in (a) language experience variables of proficiency,…

Recent decades have seen an increase in research informing our understanding of the complex ways in which bilingual development is shaped by biological, cognitive, and behavioral factors. We investigate the predictors that shape, drive, and constrain the development of the first language (L1) of bilinguals, focusing on 92 Turkish-English bilingual…