Pattern-contingent color aftereffects on noninduced patterns

Mystery of the anti-McCollough effect

“…Some displays work reliably in pairs, but not when presented singly for all subjects (e.g., yellowish red-vertical and yellowish green-horizontal; Stromeyer, 1969). In addition, a single color-orientation pair sometimes will produce an effect on the noninduced orientation (e.g., Allan & Siegel, 1991), but sometimes will not (e.g., Humphrey, Dodwell, & Emerson, 1989). For instance, when a red-vertical pairing alternated with a dark screen produces a greenish afterimage on vertical lines, it may or may not produce the so-called indirect effect, a reddish aftereffect on the noninduced horizontal lines.…”

The indirect McCollough effect: An examination of an associative account

“…Wolfe and Roorda (1990) also found an IME when they alternated a chromatic induction grating with a black field. Humphrey et al (1989;see also Dodwell & Humphrey, 1990) explained the IME by proposing that orientation coding acts in an opponent manner somewhat analogous to that of color. Thus, when a subject fixates on a grating at a certain orientation, neural mechanisms that respond maximally to that orientation become fatigued, as do mechanisms that code for color after prolonged exposure to a particular color.…”

“…In this case, subjects reported not only that concentric circle patterns appeared green and horizontal gratings appeared red, but also that radial line patterns appeared red and vertical gratings appeared green. Humphrey et al (1989) followed up on their 1985 findings and found a significant IME when they alternated a single colored pattern with a homogeneous field of a complementary Copyright 1998 Psychonomic Society, Inc.…”

“…When the grating is removed, the opponent process serves to create a relative increase in signals from mechanisms that respond maximally to a grating at an orthogonal orientation, thus creating an antagonistic rebound at the orthogonal orientation (Grossberg, 1980). Humphrey et al (1989) contended that this orthogonal rebound is paired with the complementary colored homogeneous field that is alternated with the chromatic grating and could serve as the basis of the IME induction. Humphrey et al (1989) also proposed that the IME could result from the hypothesized antagonistic rebound being paired with a colored afterimage.…”

“…Humphrey et al (1989) contended that this orthogonal rebound is paired with the complementary colored homogeneous field that is alternated with the chromatic grating and could serve as the basis of the IME induction. Humphrey et al (1989) also proposed that the IME could result from the hypothesized antagonistic rebound being paired with a colored afterimage. Others (e.g., Murch & Hirsh, 1972) have found that afterimages can serve as the colored stimulus to support an ME.…”