The role of animacy and thematic relationships in processing active English sentences: Evidence from event-related potentials

Recent event-related potential studies report a P600 eVect to incongruous verbs preceded by semantically associated inanimate noun– phrase (NP) arguments, e.g., “eat” in “At breakfast the eggs would eatƒ”. This P600 eVect may reXect the processing cost incurred when semantic–thematic relationships between critical verbs and their preceding NP argument(s) bias towards diVerent interpretations to those dictated by their sentences’ syntactic structures. We have termed such violations of alternative thematic roles, ‘thematic role violations.’ Semantic–thematic relationships are inXuenced both by semantic associations and by more basic semantic features, such as a noun’s animacy. This study determined whether a P600 eVect can be evoked by verbs whose thematic structures are violated by their preceding inanimate NP arguments, even in the absence of close semantic–associative relationships with these arguments or their preceding contexts. ERPs were measured to verbs under four conditions: (1) non-violated (“At breakfast the boys would eatƒ”); (2) preceded by introductory clauses and animate NPs that violated their pragmatic expectations but not their thematic structures (“At breakfast the boys would plantƒ”); (3) preceded by semantically related contexts but inanimate NPs that violated their thematic structures (“At breakfast the eggs would eatƒ”); (4) preceded by semantically unrelated contexts and inanimate NPs that also violated their thematic structures (“At breakfast the eggs would plantƒ”). Pragmatically non-thematic role violated verbs preceded by unrelated contexts and animate NPs evoked robust N400 eVects and small P600 eVects. Thematically violated verbs preceded by inanimate argument NPs evoked robust P600 eVects but no N400 eVects, regardless of whether these inanimate arguments or their preceding contexts were semantically related or unrelated to these verbs. These Wndings suggest that semantic-thematic relations, related to animacy constraints on verbs’ arguments, are computed online and can immediately impact verb processing within active, English sentences.