Making sense of abstract events: building event schemas.

Everyday events, such as making a bed, can be segmented hierarchically, with the coarse level characterized by changes in the actor's goals and the fine level by subgoals (Zacks, Tversky, & Iyer, 2001). Does hierarchical event perception depend on knowledge of actors' intentions? This question was addressed by asking participants to segment films of abstract, schematic events. Films were novel or familiarized, viewed forward or backward, and simultaneously described or not. The participants interpreted familiar films as more intentional than novel films and forward films as more intentional than backward films. Regardless of experience and film direction, however, the participants identified similar event boundaries and organized them hierarchically. An analysis of the movements in each frame revealed that event segments corresponded to bursts of change in movement features, with greater bursts for coarse than for fine units. Perceiving event structure appears to enable event schemas, rather than resulting from them.