Explicit attention to research design issues is essential in experimental second language (L2) research. Too often, however, such careful attention is not paid. This article examines some of the issues surrounding experimental L2 research and its relationships to causal inferences. It discusses the place of research questions and hypotheses,…

In this article, we report the results of a study on the relationship between individual differences in language learning aptitude and the structural connectivity of language pathways in the adult brain, the first of its kind. We measured four components of language aptitude ("vocabulary learning"; "sound recognition"; "sound-symbol…

Intermediate-level English as a second language students were examined for levels of reading comprehension. Half of each group (experimental and control) received more complete versions of test passages than the other half, and the experimental group was taught appropriate cultural background information between tests. Background knowledge did…