Two experiments tested infants' sensitivity to properties of point-light displays of a walker and a runner that were equivalent regarding the phasing of limb movements. Found that 3-, but not 5-month-olds, discriminated these displays. When the symmetrical phase-patterning of the runner display was perturbed by advancing two of its limbs by 25…

Assessed 13- and 20-week-olds infants' discrimination between shearing stimuli, in which columns of dots move vertically on a screen at different velocities, and foil stimuli, in which all dots move at the same velocity. Results revealed the threshold levels of dot velocity in shearing stimuli at which discrimination occurred. (BC)

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)