Ambiguity Resolution in Sentence Processing: The Role of Lexical and Contextual Information

This study investigates how the parser employs thematic and contextual information in resolving temporary ambiguities during sentence processing. We report results from a sentence-completion task and from a self-paced reading experiment with native speakers of Greek examining two constructions under different referential context conditions: relative clauses (RCs) preceded by complex noun phrases with genitives [NP1+NP2Gen] and RCs preceded by complex noun phrases containing prepositional phrases [NP1+PP[P NP2]]. We found different attachment preferences for these two constructions, a high (NP1) preference for RCs with genitive antecedents and a low (NP2) preference for RCs with PP antecedents. Moreover, referential context information was found to modulate RC attachment differently in the two experimental tasks. We interpret these findings from the perspective of modular theories of sentence processing and argue that on-line ambiguity resolution primarily relies on grammatical and lexical-thematic information, and makes use of referential context information only as a secondary resource.