Recent studies have uncovered substantial individual differences in first language (L1) language attainment across the lifespan and across multiple components of language. The existence of such variability raises the question of its role in second language (L2) learning. The existing body of research on L1-L2 relationships has primarily targeted…

We assessed the roles of first language (L1) and second language (L2) proficiency in the processing of preverbal clitics in L2 Spanish by considering the predictions of four processing theories--the Input Processing Theory, the Unified Competition Model, the Amalgamation Model, and the Associative-Cognitive CREED. We compared the performance of L1…