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…

Lexical tone languages like Mandarin Chinese require listeners to discriminate among different pitch patterns. A syllable spoken with a rising pitch (e.g. "b[i-acute]" 'nose') carries a different meaning than the same syllable spoken with a falling pitch (e.g. "b[i with grave]" 'arm'). For native speakers (L1) of a non-tonal…

Purpose: The extant literature suggests that individual differences in speech perception can be linked to broad receptive language phenotype. For example, a recent study found that individuals with a smaller receptive vocabulary showed diminished lexically guided perceptual learning compared to individuals with a larger receptive vocabulary. Here,…

An enduring question is whether language learning aptitude is a stable trait or is one influenced by experience, such as living with two languages. We investigated aptitude in bilinguals and treated their bilingual experience as an aggregate of variables, focusing on how individual differences in (a) language experience variables of proficiency,…

Over the last two decades, there has been an increasing interest in third language (L3) phonology (Cabrelli Amaro, 2012; Cabrelli Amaro & Wrembel, 2016). However, research so far has been primarily directed at specific stages of learning and has independently explored either production (e.g., Llama, Cardoso, & Collins, 2010; Llama &…

It is unknown whether and to what extent cognitive individual differences may play different roles in paper versus computer-based second language (L2) writing. This exploratory study is a first attempt to explore this issue, focusing on the effects of working memory and language aptitude on the quality of paper versus computer-based L2 writing…

Purpose: Although variability of training materials has the potential to benefit the learning of lexical tones, the benefit is contingent on an individual's pitch aptitude. Previous studies did not segregate immediate learning and consolidation after an overnight interval, and little is known about how pitch aptitude differences affect…

Individual differences (IDs) play an important role in the second language learning process and explain the varied experiences of the L2 learner. The two major IDs, language aptitude and motivation, can be primary factors in one's ultimate proficiency. While language aptitude is largely fixed, motivation is malleable and can aid in overcoming…

Test-taker characteristics (TTCs), or individual difference variables, are known to be a systematic source of variance in language test performance. Although previous research has documented the impact of a range of TTCs on second language (L2) learners' test performance, few of these studies have involved young learners. Given that young L2…

Working memory (WM) is inherently dynamic and complex, being a multi-faceted system that links storage and processing components; yet it is widely understood as internal. Hence, in second language (L2) research, its connection to complex dynamic systems theory (CDST) remains underspecified. This paper seeks to bridge a gap between CDST and WM in…

Recent research has called for the use of fine-grained measures that distinguish implicit knowledge from automatized explicit knowledge. In the current study, such measures were used to determine how the two systems interact in a naturalistic second language (L2) acquisition context. One hundred advanced L2 speakers of Japanese living in Japan…

Second language (L2) writing has been determined to be influenced by what is read, with language learners tending to borrow words and short phrases from input texts while writing (e.g., Wang & Wang, 2015). This phenomenon is referred to as lexical alignment. Only one empirical study has investigated the influence that the linguistic complexity…

Adult second language (L2) learning often exhibits great variability in its rate and outcome. Although research shows that learning trajectories are partly shaped by social and contextual factors (e.g. Larson-Hall, 2008), certain learner factors play an important role in enhancing L2 pronunciation learning by helping L2 learners notice and process…

The research on interpreting aptitude has focused on the abilities, skills and personal traits of individuals in order to predict their future interpreting performance. However, an important variable between the personal characteristics and success of trainee interpreters in interpreter training, which is instructional practices, is overlooked.…

The purpose of this study was to find out, whether three methods of presenting input, were effective in relation to language aptitude. Persian-speaking learners of English were provided with 20 grammatical collocations (verb-preposition collocations) embedded in authentic passages, lexically/grammatically elaborated passages, and…