The impact of text length on the estimation of lexical diversity has captured the attention of the scientific community for more than a century. Numerous indices have been proposed, and many studies have been conducted to evaluate them, but the problem remains. This methodological review provides a critical analysis not only of the most commonly…

Our contribution draws on quantitative data from a longitudinal mixed-methods study to uncover different patterns of social contacts of study abroad (SA) students and the relationship of these social contacts with (a) language use, (b) target language development, and (c) contextual variables. Data were obtained by means of online questionnaires…

This study investigated how students' self-reported individual differences predicted second language (L2) spoken discussion task output, an objective behavioral outcome, in the Japanese university English as a Foreign Language (EFL) context. Although numerous psychological theories are used as a rationale for task-based language teaching (TBLT),…

We investigated whether the accuracy of grammatical morphemes in second language (L2) learners' writing is associated with usage-based distributional factors. Specifically, we examined whether the accuracy of L2 English inflectional morphemes is associated with the availability (i.e., token frequency) and contingency (i.e., token frequency…

This study longitudinally examined the effects of cognitive and sociopsychological individual differences (aptitude, motivation, personality) and the quantity and quality of second language (L2) experience on L2 speech gains in naturalistic settings. We elicited L2 spontaneous speech from 50 Chinese learners of English at the beginning and the end…

Since the early 2000s, neurocognitive research on second language (L2) acquisition has been controversial as to how plastic the human brain is after puberty. Recent studies have extended this debate to first language loss (L1 attrition). This article gives an overview of the first event-related brain potential (ERP) studies on L1 attrition and L2…

Extending previous findings on adult L2 learners' integration of verbal and constructional information, this study investigated how child learners of English as a foreign language produce verbs in target constructions and whether (a) receptive skills and (b) the specific production modality (spoken versus written) modulate the integration process.…

Theories of how language works have shifted from rule-like competence accounts to more skill-like incremental learning accounts. Under these, people acquire language incrementally, through practice, and may even lose it incrementally as they acquire competing mappings. Incremental learning implies that (1) a bilingual's abilities in their…

This study examined the acquisition of preposition placement in English as a second language from a usage-based perspective. German and Chinese learners of English and English native speakers rated the acceptability of English oblique "wh" relative clauses in a magnitude estimation task. Results indicated that acceptability depended on…

The current study examined the degree to which collocation use (i.e., meaningful co-occurrences of multiple words) is related to first language (L1) raters' intuitive judgments of second language (L2) speech. Speech samples from a picture description task performed by 85 Japanese learners of English with varied L2 proficiency profiles were…

The constructionist approach holds that an argument structure construction, a conventionalized form-meaning correspondence of a sentence, allows language users to efficiently access sentential information. This study investigated whether increased sensitivity to constructional information would enable second language learners to efficiently fuse…

To date, a growing number of studies have shown that domain-general auditory processing, which prior work has linked to L1 acquisition, could explain various dimensions of naturalistic L2 speech proficiency. The current study examined the generalizability of this topic to L2 speech learning in classroom settings. The spontaneous speech samples of…

This study investigated how bilinguals' perception of their first language (L1) differs according to age of reduced contact with L1 after immersion in a second language (L2). Twenty-one L1 Korean-L2 English bilinguals in the United States, ranging in age of reduced contact from 3 to 15 years, and 17 control participants in Korea were tested…

This study presents a cross-sectional and longitudinal analysis of how 108 high school students in English as a foreign language (EFL) classrooms enhanced the comprehensibility of their second language (L2) speech according to different motivation, emotion, and experience profiles. Students' learning patterns were primarily associated with their…

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…