Is there an end in sight? Viewers' sensitivity to abstract event structure.

People segment the stream of experience into events, or temporal segments that have a beginning and an ending. But how are such event boundaries defined? Linguistic theories of event encoding draw a distinction between bounded events that include an inherent endpoint ("eat a pretzel") and unbounded events that lack such an endpoint ("eat cheerios"). Even though the literature on event cognition has not focused on such abstract aspects of event structure, we hypothesize that sensitivity to boundedness could shape the way events are processed. In the present study, we show that viewers are sensitive to event boundedness in a category identification task and distinguish it from event completion; furthermore, viewers identify bounded events more easily than unbounded events. Sensitivity to boundedness emerges even when viewers are prevented from encoding the events linguistically and thus does not depend on the online use of linguistic distinctions. We conclude that event cognition relies on highly abstract properties of events and their boundaries, and sketch implications of these findings for the way events are described, processed, and used to interact with the world.