The Role of Objecthood and Animacy in Apparent Movement Processing

Movement perception involves both motion and form processing. Previous research has shown that processing along the motion pathway requires a familiar but not necessarily a human shape. However, the role of objecthood and animacy in the form pathway is less clear. Here, we used EEG frequency tagging to study how objecthood and animacy influence both posture processing and the integration of postures into movements. Specifically, we measured brain responses to repeating sequences of well-defined or pixelated images (objecthood) of human or corkscrew agents (animacy) performing fluent or non-fluent movements (movement fluency). The results revealed that movement processing was sensitive to objecthood but not to animacy, whereas posture processing was sensitive to both. Thus, our results indicate that movement processing in the form pathway requires a familiar shape, but not necessarily a human shape. Instead, stimulus animacy appears to be relevant only for posture processing.