Perception of Depth in Rotating Objects: 2. Perspective as a Determinant of Stereokinesis

10 Os viewed under extreme reduction conditions 5 simple, plane, featureless figures and an Ames trapezoidal window as they rotated slowly (5 rpm) in the frontoparallel plane. Judgments of shape, slant, and type of movement were obtained for 4-min. periods first with binocular regard and later with monocular. As more perspective cues were introduced and as viewing time increased, there were progressive increases in depth indicants with all three types of judgments.