Proceedings of the Annual Meeting of the Cognitive Science Society

To investigate how co-speech gestures modulate linguistic understanding, we conducted an EEG experiment exploring the amplitude changes in the N400 component. We used videos of a person uttering underspecified action sentences which either featured no gesture or an iconic co-speech gesture that represented a more specific action. The following target sentence contained an instrument noun followed by its required action verb; these could either match the action represented in the previously seen gesture or mismatch it. We measured ERPs for both the nouns and the verbs and found an N400 effect for mismatching target words as well as a sustained positivity effect for both gesture conditions.