This study longitudinally examined the effects of cognitive and sociopsychological individual differences (aptitude, motivation, personality) and the quantity and quality of second language (L2) experience on L2 speech gains in naturalistic settings. We elicited L2 spontaneous speech from 50 Chinese learners of English at the beginning and the end…

Previous literature has shown that voicing contrast is a difficult feature for Chinese-English emergent bilingual learners of L3 Spanish (Bravo Diaz, 2020; Chen, 2007; Zhang, 2022). The production of voicing contrast in stops has been broadly investigated in second and third language studies (e.g., Zampini, 1998; Llama, 2010; Wrembel, 2014), but…

This paper examines evidence for relationships among individual differences (IDs) in L1 achievement, L2 aptitude, and L2 achievement. It begins by providing an overview of my academic journey from L1 educator to L2 researcher and explains the development of the Linguistic Coding Differences Hypothesis (LCDH). Next, I review Peter Skehan's…

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,…

Drawing on recent psychological and neurological research on how individual differences might interact with learning a particular language, the study examines how psycholinguistic research and theory can help in assigning military personnel to language training and to a given language. Using the Defense Language Institute's Defense Language…