UC San Diego

This dissertation examines the on-line processing and off- line acceptability judgments of whether-islands using an individual differences approach in order to test processing accounts of island phenomena. Processing accounts of islands propose that the unacceptability of an island violation can be attributed to difficulties in on- line processing, but accounts differ in how this difficulty is characterized, based on the view of working memory adopted. The three experiments reported here (acceptability judgments, Chapter 4; self-paced reading, Chapter 5; event-related potentials- ERPs, Chapter 6) test the capacity-constrained account of islands (e.g. Kluender 1991), based on working memory as capacity-constrained (Just & Carpenter 1992), as well as a novel ̀similarity- interference' account of islands (Chapter 2) based on working memory as subject to similarity-based interference (e.g. Gordon, Hendrick & Johnson 2001; Lewis, Vasishth & Van Dyke 2006). I introduce two frameworks (Chapter 4) - the Cognitive Co-variation Intuition (CCI) and the Processing Benefits Schedule (PBS) - to clarify the relationship between off-line acceptability, on-line processing and individual differences (i.e. reading span, memory interference). Ultimately, the data reported here do not support a view where processing factors directly and transparently predict the unacceptability of island violations (neither do they directly support a grammatical account of islands). However, the ERP data indicate the importance of real time prediction for the on-line processing of islands. This is formalized as the gap predictability account of processing islands (Chapter 7). Specifically, high span readers are better able to adjust their predictions for a gap online (evidenced by an N400 response at the embedded gap, suggesting lowered expectation for a gap in an island context), but both high and low span readers show evidence of filler-gap association (evidenced by post-gap LANs). There was no evidence of a failed parse or reanalysis in any condition or in any group of participants, as predicted by both processing and grammatical accounts, yet these same participants still rated island violations as the least acceptable sentences. There is no apparent ERP evidence of a large on-line processing cost that would account for this difference in acceptability. These island violations appear to be unacceptable, but not unparseable