Animacy matters: ERP evidence for the multi-dimensionality of topic-worthiness in Chinese

An event-related potential (ERP) study was conducted to investigate how animacy interacts with givenness during topic processing. Both animacy and givenness have been considered as within-discourse factors that contribute to an element׳s potential to form an optimal topic (i.e., topic-worthiness). ERPs were recorded while participants read question-answer pairs, of which the target sentence induced either a continuation or an alternation of a previously introduced topic (i.e., given vs. new). Depending on the context, a potential topic further differed in its animacy from the preceding one (i.e., animate vs. inanimate). The data revealed a robust givenness effect with an N400 reduction for given over new information across all conditions, substantiating the assumption that the N400 amplitude varies with the degree of context-based expectation. The resulting N400 effect was found independently of animacy. More strikingly, we also observed that givenness interacts with animacy in modulating the subsequent Late Positivity effect, which has been suggested to reflect internal discourse structuring effort and updating. A more pronounced Late Positivity was consistently elicited when a less prominent entity competed for topichood. Most crucially, the present research provides first electrophysiological evidence indicating that animacy outweighs givenness as a heuristic cue in determining the degree of topic-worthiness.