Nick Ellis is Professor of Psychology at University of Michigan, Ann Arbor. His research interests address a range of issues in applied psycholinguistics. He has published broadly in the areas of first and second language acquisition; implicit and explicit learning; dyslexia; vocabulary acquisition; the role of working memory; and computational modeling. He was the editor of Language Learning from 1998-2002. Consideration of usage-based and connectionist models of language and their insights for second language learning have been important themes in his research for the past several years. His most recent work focuses on frequency effects and their possible implications for second language acquisition.