We describe how motion of either the infant or of objects in the world makes it possible for infants to solve a number of tasks involving occlusion. The influence of motion is seen at different levels in visual processing. First, there is evidence that young infants exploit lawful transformations in the retinal projection to perceive surface boundaries, the relative depth of surfaces at a boundary, figure-ground relations, and the invariant shape of an object that is being occluded. Second, young infants use the common motion, in three-dimensional space, of the visible parts of a partially occluded object as information for the unity of the object. In contrast to the early development of these abilities, recent work suggests that it is not until the end of the first year of life that infants are able to integrate successive partial views of an object into a unified representation.
Bibliographical noteFunding Information:
This work was supported by NICHHD grant HD-07205-10 and by a dissertation fellowship from the University of Minnesota, awarded to the first author. We would like to thank Ann Benson, Kristin Krueger, Paula Nelson, Leesa Slater, and Brenda Talbot for their assistance in collecting the data reported here.