Individual Differences and Instructed Second Language Acquisition: Insights from Intelligent Computer Assisted Language Learning

Abstract

The present dissertation focuses on the role of cognitive individual difference factors in the acquisition of second language vocabulary in the context of intelligent computer assisted language learning (ICALL). The aim was to examine the association between working memory and declarative memory and the learning of English phrasal verbs in a web-based ICALL-mediated experiment. Following a pretest-posttest design, 127 adult learners of English were assigned to two instructional conditions, namely meaning-focused and form-focused conditions. Learners in both conditions read news texts on the web for about two weeks; learners in the form-focused condition additionally interacted with the texts via selecting multiple-choice options. The results showed that both working memory and declarative memory were predictive of vocabulary acquisition. However, only the working memory effect was modulated by the instructional context, with the effect being found exclusively in the form-focused condition, and thus suggesting the presence of an aptitude-treatment interaction. Finally, findings also revealed that learning during treatment in the form-focused group was nonlinear, and that paying attention to form and meaning simultaneously impeded global reading comprehension for intermediate, not advanced learners. From a theoretical perspective, the findings provide evidence to suggest that individual differences in both working memory and declarative memory affect the acquisition of lexical knowledge in ICALL-supported contexts. Methodologically, the current study illustrates the advantages of conducting interdisciplinary work between ICALL and second language acquisition by allowing for the collection of experimental data through a web-based, all-encompassing ICALL system. Overall, the present dissertation represents an initial attempt at characterizing who is likely to benefit from ICALL-based interventions.