McCollough effects: Experimental findings and theoretical accounts.

Abstract

McCollough effects, a group of visual contingent aftereffects involving color and contour, have been the subject of a recent body of literature. While a number of investigations have simply reported variations of the original phenomenon, others have closely examined characteristics of these effects and the conditions under which they can be optimally produced. Indications that their spatial specificity is similar to that of single cortical cells investigated electrophysiologically in animals have inspired several models; however, the extraordinary persistence of the effects is difficult to explain at a single-unit level. -Findings which suggest that McCollough effects have characteristics like those of learned responses may help to resolve this paradox.

Orientation-contingent tactual size aftereffects

“…McCollough suggested that color-coded orientation-specific edge detectors might account for the observed contingent aftereffect-and, indeed, a few such detectors were later found in the visual cortex of the monkey (Hubel & Wiesel, 1968). Nevertheless, McCollough's explanation has been criticized on several grounds (Harris & Gibson, 1968;Murch, 1972Murch, , 1976Skowbo, Timney, Gentry, & Morant, 1975). …”

Stereopsis and binocular rivalry.

“…It is not clear why this aftereffect should behave in an atypical fashion, though, as noted above, color is often the exception to simple rules of binocular vision. In this specific case, it is probably significant that most color-contingent aftereffects do not show normal IOT (e.g., Skowbo, Timney, Gentry, & Morant, 1975;White, Petry, Riggs, & Miller, 1978). Mack and Chitayat (1970) also adapted each eye to different stimuli.…”

Scotopic and photopic thresholds : a dependent variable for the McCollough effect

“…Following brief (5 sec) and prolonged (15 sec) adaptation to horizontally or vertically lined grids paired with varying background colors, Timney, Gentry, Skowbo and Morant (1975) measured luminance thresholds for test fields of identical or differing orientation and wavelength. After inspection trials, observers were required to manually adjust a neutral density wedge until such time that the subjective colors were just apparent on the test target.…”

“…Objections have also been raised regarding the efficacy of certain color-cancellation procedures. Although Teft and Clark (1968) proposed to measure changes in test pattern orientation, Skowbo et al (1975) commented that what was actually being measured was bandwidth; the range of spatial frequencies over which the effect remained visible.…”

“…Since that time, a multitude of variations on the original experiment nstrating the effect have been reported (see for reviews Harris, 1980;Skowbo, 1984; Skowbo, Timney, Gentry and Morant, 1975), and although it has I been established repeatedly that the color-contingent aftereffects are 1rather simple to evoke, finding a way to adequately quantify them has uch more challenging and difficult task (Skowbo et al, 1975).…”