Karsten Steinhauer

McGill University
Talk Title: 
How critical is the critical period in second language acquisition? Evidence from event-related brain potentials
Event Type: 
Linguistics Lecture Series
Thursday, November 4, 2010, 6:00 pm - 8:00 pm
Humanities 1006

How critical is the critical period in second language acquisition? Evidence from event-related brain potentials

Karsten Steinhauer
Language acquisition in childhood is less effortful and seems more efficient than in adulthood. These differences are often explained in terms of an early 'critical period'  in life, after which maturational changes in brain plasticity prevent second language (L2) learners from  relying on the same neuro-cognitive mechanisms as native speakers. While this Critical Period  Hypothesis  initially received support from various behavioral and brain imaging studies, more recent work has cast new doubt on its assumptions, especially in the domain of morpho-syntax.
Event-related brain potentials (ERPs) provide an excellent tool to investigate the temporal dynamics of language processing, including the fascinating neural changes that take place when language learners become more proficient in their L2. In my talk, I will first give a brief introduction to this technique and then present data from a variety of large-scale ERP studies investigating second language acquisition in both artificial and natural languages. I will demonstrate that there is little evidence for a strict critical period in the domain of late acquired L2 morpho-syntax and that L2 proficiency rather than age of language acquisition predicts the brain's activation patterns, including "native-like" activity at very high levels of proficiency. Moreover, I will argue that a strict distinction between linguistic structures that late L2 learners can versus cannot learn to process in a native-like manner may not be warranted. Instead, morpho-syntactic real-time processing in general seems to undergo dramatic, but systematic, changes with increasing proficiency. The general dynamics of these changes, however, is modulated by factors such as one's first language background (e.g., Francophone vs. Chinese learners of English) and the type of language exposure (e.g., immersion versus classroom instruction). In my conclusion, I will outline how future ERP research can further advance our understanding of language learning.