In this talk, I explore the extent to which adult L2 learners activate the first-language (L1) syntax in L2 sentence production and comprehension. One of the hallmarks of adult L2 acquisition is that learners transfer properties of the L1 grammar, especially in the beginning stages of L2 acquisition. However, the degree of L1 activation in real-time L2 processing is less clear: While L1 effects are well documented for the use of inflection in L2 processing, there is little evidence of the co-activation of L1 syntactic structure in L2 processing.

I will present a series of visual-world eye tracking and primed production studies that test the degree to which adult L2 learners license L1 parses or recruit the L1 syntax in production. Across comprehension and production, the findings suggest a rather limited degree of L1 effects that obtain only under specific circumstances. I will discuss these results in the context of current approaches to L2 processing.