This article focuses on a theoretical and empirical exploration of developmental trajectories and individual learner variation in second language (L2) acquisition. Taking a processability perspective, I view learner language as a dynamic system that includes predictable universal developmental trajectories as well as individual learner variation,…

Idealization plays a fundamental role in scientific inquiry. This article examines the case for maintaining the claim that the second language acquisition (SLA) of grammatical structures such as negation manifests identifiable stages of acquisition. It proposes that, while research has demonstrated the need for de-idealization, there is no need to…

This study uses conversation analysis (CA) to investigate the coupling of specific linguistic items with specific gestures in second language (L2) learning over time. In particular, we are interested in how gestures accompany learning of new vocabulary. CA-informed studies of gesture have previously shown the importance of embodiment in L2 use and…

The current study was designed to assess the central claim of the Teachability Hypothesis (TH), a corollary of general Processability Theory (PT), which predicts instruction cannot alter posited universal, hierarchically organized psycholinguistic constraints behind PT's developmental sequences. We employed an interventional design, which adhered…

I propose that the course of development in first and second language acquisition is shaped by two types of processing pressures--internal efficiency-related factors relevant to easing the burden on working memory and external input-related factors such as frequency of occurrence. In an attempt to document the role of internal factors, I consider…

The traditional morpheme order studies in second language acquisition have tried to demonstrate the existence of a fixed order of acquisition of English morphemes, regardless of the second language learner's background. Such orders have been taken as evidence of the preprogrammed nature of language acquisition. This article argues for a…

This article considers explicit knowledge and processes in second language (L2) learning from a usage-based theoretical perspective. It reports on the long-term development of a single instructed adult learner's use of two L2 constructions, the German Perfekt of "gehen" ("go," "walk") and "fahren"…

Over the past several decades, researchers have discovered a great deal of information about the processes underlying language acquisition. From as early as they can be studied, infants are sensitive to the nuances of native-language sound structure. Similarly, infants are attuned to the visual and conceptual structure of their environments…

Drawing on usage-based linguistics and its exemplar-based path of language learning, from recurring multiword expressions to increasingly abstract, schematized constructions, this article examines evidence for the exemplar-based developmental sequences for yes/no interrogatives and WH interrogatives in English as a second language (L2). The…

In the past 15 years, a substantial body of evidence has confirmed that a powerful distributional learning mechanism is present in infants, children, adults and (at least to some degree) in nonhuman animals as well. The present article briefly reviews this literature and then examines some of the fundamental questions that must be addressed for…

Although the significance of age in second language acquisition is one of the most hotly debated issues in the field, very few studies have directly addressed age differences in the language learning process. The present study investigated learning in a foreign-word repetition task. Young Finnish adults and 8-year-olds repeated back Korean words.…

Humans are remarkably sensitive to the statistical structure of language. However, different mechanisms have been proposed to account for such statistical sensitivities. The present study compared adult learning of syntax and the ability of two models of statistical learning to simulate human performance: Simple Recurrent Networks, which learn by…

Although there is good evidence for implicit learning of associations between forms, little work has investigated implicit learning of form-meaning connections, and the findings are somewhat contradictory. Two experiments were carried out using a novel reaction time methodology to investigate implicit learning of grammatical form-meaning…

This article extends recent findings that presenting semantically related vocabulary simultaneously inhibits learning. It does so by adding story contexts. Participants learned 32 new labels for known concepts from four different semantic categories in stories that were either semantically related (one category per story) or semantically unrelated…

For decades educational psychologists have bemoaned the black box approach of much research on learning, that is, the focus on product rather than process, and the absence of fine-grained analysis of the learning process in the individual. One way that progress has been made on this point in the last couple of decades is through cognitive…