This article presents a theoretical review of and methodological guidelines for the study of two key notions in second language acquisition research, complexity and difficulty. The term "complexity" has gained considerable currency over the past decades and has taken on a wide range of meanings. We argue for a more restricted…

Second language (L2) grammar learning is difficult. Two frameworks--the psycholinguistic lexical bottleneck hypothesis and the neurocognitive declarative/procedural model--predict that faster L2 lexical processing should facilitate L2 incidental grammar learning. We tested these predictions in a pretest-posttest syntactic adaptation study of…

This article responds to calls for greater inclusivity in second language acquisition research and, more specifically, to calls to explore further the impact of first language literacy on second language oracy (e.g., Tarone et al., 2009). We conducted a partial replication of Foster and Skehan's (1996) influential study of task complexity,…

This study reports on a self-paced reading experiment exploring whether the figurativeness of collocations affects L2 processing of collocations. The participants were 40 English native speakers and 44 Chinese-speaking English foreign language learners (including doctoral, postgraduate, and undergraduate students). To ensure that the effect…

Event segmentation tests have shown substantial overlaps in how adults recognize starts and endpoints as events unfold. However, far less is known about what role different language systems play in the process. Variations in grammatical aspect have been shown to influence event processing. We tested how closely first language (L1) speakers of…

Eye tracking has taken hold in second language acquisition (SLA) and bilingualism as a valuable technique for researching cognitive processes, yet a comprehensive picture of reporting practices is still lacking. Our systematic review addressed this gap. We synthesized 145 empirical eye-tracking studies, coding for 58 reporting features and…

Participants learned the meaning of novel objects by listening to two complementary definitions while watching videos of the new object, in a single-language context (all in Spanish) or a mixed-language context (one definition in Basque, one in Spanish). Then, participants were asked to assess the degree of functional relatedness between novel and…

This study used eye-tracking to examine changes in how second language (L2) learners process target grammatical exemplars in written L2 input in implicit and explicit instructional conditions and how these changes relate to learning gains. In three separate sessions, 77 L2 learners of English read a story containing seven examples of a grammatical…

Research in adults has shown that novel words are encoded rather swiftly but that their semantic integration occurs more slowly and that studying definitions presented in a written modality may benefit integration. It is unclear, however, how semantic integration proceeds in children, who (compared to adults) have more malleable brains and less…

This study investigated whether task complexity influences second language (L2) writers' fluency, pausing, and revision behaviors and the cognitive processes underlying these behaviors; whether task complexity affects linguistic complexity of written output; and whether relationships between writing behaviors and linguistic complexity are…

This study explored learners' self-generated noticing of L2 input. It is motivated by previous research on input enhancement which suggested that learners are able to notice certain aspects of input on their own without any external means to direct their attention. Drawing on insights that learner-generated noticing is largely mediated by…

The present study investigates the role of speech repetition in oral fluency development. Twenty-four students enrolled in English-as-a-second-language classes performed three training sessions in which they recorded three speeches, of 4, 3, and 2 min, respectively. Some students spoke about the same topic three times, whereas others spoke about…

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…

Studies about bilingualism and second language acquisition (SLA) have a long tradition within linguistic and psycholinguistic research. The contributions from psycholinguistic research are crucial to the improvement of neurolinguistic models. This importance stems from the fact that psycholinguistic research is posing more specific questions than…

A conceptual replication of Izumi and Bigelow's research, this study used multiple measures to investigate second language (L2) learners' processes in output-input-output sequences. Specifically, it examined whether producing the target language impacts learners' attention to L2 structures in subsequent input. Thirty learners of English as a…