The roles of pattern orthogonality and color contrast in the generation of pattern-contingent color aftereffects

Contingent color aftereffects: Reassessing old conclusions

“…As in the previous five experiments in this report, the CCAEs were assessed using the method ofconstant stimuli. The method ofconstant stimuli has been shown to be more sensitive in revealing the presence of CCAEs than the color-naming procedure used by Humphrey et al (1985;see Allan et aI., 1991;Humphrey, Herbert, et aI., 1994;Humphrey, Skowbo, et aI., 1994).…”

“…Humphrey et al (1985) attempted to induce orientation CCAEs by alternating presentations of same-color patterns (e.g., green-horizontal and green-vertical). They reported orientation CCAEs after complementarily colored induction but not after same-color induction.…”

“…The assessment figures used by Humphrey et al (1985) were composites consisting of various arrangements of the induction (and also noninduction) patterns. Such composite assessment figures allow for simultaneous color contrast during assessment (see Stromeyer, 1984).…”

“…Experiment 6 was designed to investigate further the presence of orientation CCAEs after same-color induction. In an attempt to enhance the establishment of the CCAEs, the induction time was increased from the 10 min used in Humphrey et al (1985) to 15 min. As in the previous five experiments in this report, the CCAEs were assessed using the method ofconstant stimuli.…”

“…Broerse and Grimbeek (1994) and , in contrast, suggested that the induced aftereffects are retinotopic, and that forms constructed of the same orientation components do not elicit spatiotopic CCAEs. Humphrey, Dodwell, and Emerson (1985) attempted to induce orientation CCAEs with orthogonal grids of the same color (same-color induction) rather than ofcomplementary colors. They reported that after same-color induction (e.g., green-horizontal and green-vertical), CCAEs were not induced on either grid orientation.…”