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…

Using the lenses of bilingualism and social justice, I reflect on relevant conceptual and methodological issues encountered in the study of the linguistic development of heritage language speakers. Themes examined include the early but varying timing of heritage language learning; the surrounding linguistic environment, including the link between…

This investigation aimed to provide insights into the controversial debate on the role that age at onset of bilingualism plays in human language capacity with a focus on what it entails for first language (L1) attrition. L1 performance of Turkish immigrants (n = 57) in the United Kingdom with age at onset ranging between 7 and 34 years was…

This study investigated the influence of cognitive ability on bilingual children's vocabulary development in both their languages. Sixty-nine bilingual immigrant children participated, with data collected at three annual intervals. At Time 1, the participants were 5 or 6 years old. Receptive vocabulary was tested in the minority (Turkish, Tarifit)…

This study compares the performance of native speakers and adult second language (L2) learners on tasks tapping proficiency in grammar, vocabulary, and collocations. In addition, data were collected on several predictors of individual differences in linguistic attainment, including some related to language experience (print exposure, education,…

We examined case-marking variation in heritage Polish, Russian, and Ukrainian. Comparing heritage to homeland Polish and Ukrainian speakers, we found only a few types and a few tokens of systematic distinction between heritage and homeland varieties. A total of 6,291 instances of nouns and pronouns were extracted from transcribed conversations…

The effect of age of acquisition on ultimate attainment in second language learning has been a controversial topic for years. After providing a very brief overview of the ideas that are at the core of the controversy, I discuss the two main reasons why these issues are so controversial: conceptual misunderstandings and methodological difficulties.…

Researching the longitudinal development of second language (L2) learners is essential to understanding influences on their success. This 7-year study of oral skills in adult immigrant learners of English as a second language evaluated comprehensibility, fluency, and accentedness in first-language (L1) Mandarin and Slavic language speakers. The…

The study examined differences in reading achievement and mastery skill development among Grade-6 students with different language background profiles, using cognitive diagnosis modeling applied to large-scale provincial reading test performance data. Our analyses revealed that students residing in various home language environments show different…

It is widely assumed that ultimate attainment in adult second language (L2) learners often differs quite radically from ultimate attainment in child L2 learners. This article addresses the question of whether learners at different ages also show qualitative differences in the process of L2 acquisition. Longitudinal production data from two…

Explored the relationship of similarity, dissimilarity, and markedness to second language, specifically English, phonological acquisition. The article hypothesized that the rate of acquisition for a dissimilar phenomenon is faster than for a similar phenomenon. Findings revealed that degree of markedness can increase or decrease rate. (38…

Studies investigating the possible effects of age at immigration (a proxy for age at onset of second language learning) on second language acquisition among immigrants often explicitly take the effect of length of residence in the destination country (a measure of exposure to opportunities to learn the second language) into account. A third…

Describes a study which examined the relationship between learner chatacteristics and achievement in French as a second language. Results indicate that subjects who have more schooling, a higher degree of nonverbal reasoning ability, and make greater use of French outside the classroom are more likely to benefit from formal language instruction.…

Describes a research project carried out in Sweden to study the acquisition of Swedish syntax of negation by adult second language learners. (CFM)

Earlier version of this paper presented at the Modern Language Center, Ontario Institute for Studies in Education, Toronto, Canada. (RS)