Investigative Ophthalmology & Visual Science, Vol 19, 321-324, Copyright © 1980 by Association for Research in Vision and Ophthalmology

ARTICLES AND REPORTS

The McCollough effect in rhesus monkey

WM Maguire, GE Meyer and JS Baizer

After viewing red vertical stripes and green horizontal stripes, the eye subsequently views white vertical stripes as greenish and white horizontal stripes as pinkish. It has been theorized that this phenomenon, known as the McCollough effect, is related to long-tern adaptation of cells tuned for both color and orientation. Such cells have been found in the visual cortex of the rhesus monkey. We asked whether rhesus monkeys, like man, experience a McCollough effect. Two humans and two rhesus monkeys were adapted by requiring them to fixate a spot moving slowly across alternating horizontal and vertical gratings of complementary color. Following adaptation, a test grating whose color changed from red to green or green to red was presented. Humans and monkeys were instructed or trained to release a response lever during the interval that the grating was white. After adaptation, there were orientation-specific changes in all four subjects' responses as would be predicted if both man and monkey were experiencing a McCollough effect.