Abstract

Despite the long standing interest in stage-theories of human color vision, little thought had been given to the processing of the output of traditional opponent mechanisms until Krauskopf et al (1986a,b) presented the first experiments to address this issue. The original evidence for post-opponent mechanisms came from the habituating effect of prolonged simultaneous stimulation of the two chromatic cardinal mechanisms of Krauskopf et al (1982). Under the hypothesis that prolonged stimulation leads to independent "fatigue" of the two mechanisms, the effect of habituation should be greatest along one or the other of the cardinal directions, irrespective of the habituating color direction. This hypothesis was rejected because the maximum effect was always in the habituating direction. Krauskopf et al (1986a) suggested that the results were compatible with habituation within multiple higher order mechanisms.

© 1992 Optical Society of America