Linguistic explanations of non-nativeness in second language acquisition and the critical period hypothesis

Abstract

What type of explanation for persistent non-nativeness in older second language learners is compatible with the claim that L2 mental grammars are derived from Universal Grammar? This article argues that non-linguistic explanations, such as interference in the acquisition process by general problem-solving abilities or affective factors, are less plausible than accounts which claim that a subpart of Universal Grammar itself is subject to a critical period. It is further suggested that debate between proponents of the linguistic accounts is likely to lead to progress in understanding how the language faculty is involved in second language acquisition.