Variation in hue of a contour-contingent aftereffect due to color adaptation during inspection of the stimulus patterns

The McCollough Effect (a colored line-orientation-contingent aftereffect) has been attributed to the presence of edge detectors specific to wavelength in the human visual system. The present study tests this hypothesis by introducing unlined colored fields into the inspection condition and by comparing the subsequent aftereffect with the aftereffect induced by the inspection condition not including the unlined colored fields. The data indicate that the hues of the aftereffects differ, suggesting that the color and line stimuli may be processed by different populations of neural elements, and that the color-coded edge detector model is not adequate to account for the observations.