Figure 1. Experiment 1 stimuli.

A) Illustration of Anstis and Cavanagh's minimum motion technique that was used to determine equivalent brightness for red and green in each of eight locations (shown with dotted lines). Two square-wave gratings, one of red and green bars and one of light yellow and dark yellow bars, alternate rapidly with each subsequent grating a quarter cycle (half a bar width) offset from the previous one. The gratings were presented for one second at a time. B) The color with greater luminance will seem to track with the lighter yellow bars, moving left if the green bars have greater luminance (1) and right if the red bars have greater luminance (2). C) Examples of stimuli used for rivalry trials: Orthogonal green-and-black and red-and-black gratings overlap to create rivalry in each of the eight outlined locations of the visual field. Using a mirror stereoscope, the left and right circles were overlaid such that the rivalry targets were presented to the same retinal location of the left and right eye respectively. The gray dotted outlines of the eight locations are shown here for the purposes of illustration only and were not part of the experimental display.