The P600 is an event-related brain potential (ERP) typically associated with the processing of grammatical anomalies or incongruities. A similar response has also been observed in fully acceptable long-distance "wh"-dependencies. Such findings raise the question of whether these ERP responses reflect common underlying processes, and what…

Event-related potentials were measured as subjects read sentences presented word by word. A small N400 and a robust P600 effect were elicited by verbs that assigned the thematic role of Agent to their preceding noun-phrase argument when this argument was inanimate in nature. The amplitude of the P600, but not the N400, was modulated by the…