Figure 5.

Stimuli for Experiment 5: Contrast-modulation motion with a static random texture carrier. (a) Intensity profile of one row of a contrast modulated texture. In alternate vertical stripes within a stimulus frame, binary random noise (−1, +1) is multiplied by 0.25 and 0.75 to produce a 50% contrast modulation. (b) Intensity profile of one row of a luminance-modulated texture. In alternate vertical stripes, either 0.25 or −0.25 was added to each pixel intensity. (c) Five frames of a static texture-modulated (second-order) motion stimulus. In a static texture-modulation motion stimulus, the texture pattern remains the same from frame to frame, the imposed 0.25–0.75 contrast modulation translates 90° to the right in successive frames. (d) Five frames of a sandwich stimulus in which the odd frames are made of contrast modulated texture, and the even frames are made of luminance modulated texture.