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Researched and produced by Molly Estes
Johnson, J & Newport, E. (1989). Critical period effects in second language learning: the influences of maturational state on the acquisition of English as a second language. Cognitive Psychology, 21, 60-99.
Mayberry, R., Lock, E., & Kazmi, H. (2002). Linguistic ability and early exposure. Nature, 417, 38.
Morford, J. & Mayberry, R. (2000). Language acquisition by eye (p.111-128). Mahwah, NJ: Lawrence Erlbaum and Associates.
Morgan, G. & Kegl, J. (2006). Nicaraguan sign language and theory of mind: the issue of critical periods and abilities. Journal of Child Psychology and Psychiatry, 47:8, 811-819.
Special thanks to Dr. Deborah Chen Pichler for making this happen.