Research into second language acquisition (SLA) has shown that individual difference (ID) variables can be strong predictors of language achievement (e.g., Dornyei, 2003; Skehan, 2003). Traditionally, this research conceptualized ID variables as static and monolithic variables (e.g., Dornyei, 2010). More recently scholars have questioned this…

To date, most classroom-based research into the learning of a third language (L3) in the US has examined patterns of acquisition among various groups of bilinguals. Situated mainly within the context of "Portuguese for Spanish Speakers" (PSS), studies typically group learners based on the sequence / age of onset of their main background…

Guided by Dynamic Systems Theory (DST) and multidimensional perspectives on individual differences (IDs) in instructed second language (L2) learning (e.g., Larsen-Freeman, 2014; Sun & Zhang, 2020), this longitudinal mixed-methods study focuses on three conceptually different categories of L2 learners' IDs: working memory (WM), motivation, and…

Millions engage in learning a Second Language (L2) using their mobile devices with a wide range of success. Concomitantly, there exists a growing interest in research on the effects of mobile-assisted language learning and predictors of learner outcomes (e.g., Loewen et al., 2020; Sudina & Plonsky, 2023). However, few of these apps and studies…

This three-paper dissertation addresses the manner in which students' intrinsic motivation to engage in academic tasks changes during the four years of college. The first paper examines the variance of students' academic motivation during college. The second paper analyzes whether good practices in undergraduate education promote academic…

This action research study was designed to elicit urban, secondary school teachers' understandings of themselves as adult learners and their perceptions of job-embedded professional development in a single, urban school district in Connecticut. The conceptual framework that guided this study was derived from Knowles, Holton, and Swanson's (2011)…

This study examined the second language (L2) development of adult learners of Spanish at three levels of proficiency during and after a semester of instruction. A fundamental goal was to identify cognitive and psychosocial individual differences (IDs) that can explain between-learner variation over time in order to expand our understanding of the…

Reading in another language (L2) is a complex, multidimensional process dependent upon both reader-based and text-based factors. The purpose of this study was to investigate the roles of reader-based individual difference variables and of the text-based variable of genre in reading comprehension in French. The sample included 153 adult learners…

Bilingualism (Sanz, 2000), motivation (Pintrich, 1989), and language aptitude (Grigorenko, Sternberg, and Ehrman, 2000) are crucial individual differences that contribute to successful adult language learning. Since Gardner's (1985) seminal work on motivation, many studies have shown that motivation is dynamic and that it affects language…