John H. Schumann is Professor of Applied Linguistics at the University of California at Los Angeles. He has a doctoral degree in education with a specialization in human development from Harvard University. His research includes work on second language acquisition, the neurobiology of language, and the evolution of language. He is the author of The Neurobiology of Affect in Language (Blackwell, 1997) and is a co-author of The Neurobiology of Learning (2004). Peter Indefrey is Principal Investigator at the F.C. Donders Centre for Cognitive Neuroimaging in Nijmegen and, together with Marianne Gullberg, Head of the research project "The Dynamics of Multilingual Processing" at the Max Planck Institute for Psycholinguistics. He has a M.D. and a Ph.D. in Linguistics from the Heinrich Heine University Dusseldorf. His research is on first and second language processing and its neural correlates. Some of his favorite topics are syntactic and morphological processing, word production, reading, and the development of language processing in L2 learners. He has published in a variety of journals, including Cognition, PNAS, Neuroimage, Journal of Experimental Psychology, Brain and Language, and Journal of Cognitive Neuroscience. Marianne Gullberg is a Scientific Staff member at the Max Planck Institute for Psycholinguistics in Nijmegen and, together with Peter Indefrey, Head of the research project "The Dynamics of Multilingual Processing" at this Institute. She holds a Ph.D. in Linguistics from Lund University, Sweden. Her research focuses on the processing of second and third languages, particularly at the earliest stages of acquisition and at the advanced or bilingual stage. Topics covered range from lexical semantics, implicit learning, cross-linguistic (bi-directional) influences, code-switching, and the production and comprehension of gestures in a cross-linguistic perspective. She has published in a variety of journals, including Language Learning, Journal of Child Language, and Pragmatics & Cognition.