A fundamental question of perceptual development concerns how infants come to perceive partly hidden objects as unified across a spatial gap imposed by an occluder. Much is known about the time course of development of perceptual completion during the first several months after birth, as well as some of the visual information that supports unity…

Twenty congenitally blind infants were placed in a panelled framework with various tactile and auditory objects for 20-minute periods. Results indicated that subjects improved their performance of spatially related activities when exposed to an environment helping them understand the concept and permanence of objects and the production of…