Spatiotemporal integration and object perception in infancy: perceiving unity versus form.

3 experiments investigated 5-month-old infants' perception of an object whose center was fully occluded and whose ends were visible only in succession. Infants perceived this object as one connected whole when the ends of the object underwent a common motion behind the occluder, but not when the ends were stationary. Although infants perceived the connectedness of the object, they did not appear to perceive the object's shape. These findings suggest (a) that young infants are capable of integrating information over time to perceive object unity but not object form, (b) that young infants perceive object unity in accord with basic constraints on object motion, and (c) that a common process underlies infants' perception of objects that are fully visible, objects that are partly occluded, and objects that move fully out of view.