This study examined infants' use of object knowledge for scaling the manipulative force of object-directed actions. Infants 9, 12, and 15 months of age were outfitted with motion-analysis sensors on their arms and then presented with stimulus objects to examine individually over a series of familiarization trials. Two stimulus objects were used in…

The emerging ability to represent an oscillating moving object over occlusions was studied in 7-21-week-old infants. The object moved at 0.25 Hz and was either occluded at the center of the trajectory (for 0.3 s) or at one turning point (for 0.7 s). Each trial lasted for 20 s. Both eye and head movements were measured. By using two kinds of…

Two experiments examined the effects of common motion, background texture, and orientation on four-month olds' perception of unity of a partially occluded rod. Results indicated that infants' perception of object unity is not dependent on a single visual cue but on a variety of cues including motion, interposition, depth cues, background texture,…

Three experiments examined 4- and 6-month-olds' sensitivity to the unity of a partly occluded moving rod undergoing translation, rotation, or oscillation. Findings suggested that all types of common motion were not equivalent for specifying infants' perceptions of occluded objects. (Author)

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…