Professor MacWhinney argues that second language learning uses the same processes as first language learning. Here is a research paper: A Unified Model of Language Acquisition.
Brian MacWhinney is Professor of Psychology, Computational Linguistics, and Modern Languages at Carnegie Mellon University.
Interview with Professor MacWhinney.
The Neuroscience of Language and Learning
Dr. Karen Froud, associate Professor of Speech Language Pathology and Neuroscience and Education at Teacher’s College.
Professor Stephen Grossberg