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…

In this article, we challenge the notion that aptitude--operationalized as grammatical sensitivity as measured by the Words in Sentences section of the Modern Language Aptitude Test--is central to adult second language (L2) acquisition. We present the findings of a study on the acquisition of two properties of Japanese, head-final word order and…

Students at the United States Air Force Academy (USAFA) are required to study a foreign language. In order to place students into appropriate language courses, especially less commonly taught languages defined by the American Council on the Teaching of Foreign Languages (ACTFL), effective language placement policies are essential. The author…

Finding the match between individuals and educational treatments is the aim of both educators and the aptitude-treatment interaction research paradigm. Using the latent growth curve analysis, the present study investigates the interaction between the type of explicit instructional approaches (deductive vs. explicit-inductive) and the level of…