A new phenomenon of color vision is described. An observer, viewing only a uniform physical field, finds that his perceptual field suddenly becomes broken up into areas (called pattern and background) that exhibit two very different colors. The pattern arises suddenly, and lasts only a few sec. It has an irregular, blotchy shape and may be 45° or more in width (becoming smaller in successive experiments and finally remaining absent entirely).
The creation of the pattern depends on the spectral energy distribution (not the color) of the physical field. Wavelengths near 570 mµ and 470 mµ play crucial and antithetical roles.
The color of the pattern depends on the spectral distribution of the physical field being viewed currently. The color is neither similar to nor complementary to that of the background or any preceding field.
To tie together the wealth of observations as to color, duration, and sequence effects of the patterns, one may postulate that the perceptual field-of-view is governed (as regards yellowness/blueness ratio only) by hundreds of radiation-actuated switches arranged in parallel. Each switch is of three-position type, and can produce normal yellowness/blueness ratio, extremely high (anomalous) ratio, or extremely low (anomalous) ratio. By referring to the postulated design of the switch, an investigator can predict the results of nearly any pertinent experiment.
WILLIAM A. SHURCLIFF, "New Visual Phenomenon: The Greenish-Yellow Blotch," J. Opt. Soc. Am. 49, 1041-1041 (1959)