Spatial filtering versus anchoring accounts of brightness/lightness perception in staircase and simultaneous brightness/lightness contrast stimuli.
J. Cataliotti and A. Gilchrist (1995) reported that, consistent with anchoring theory, the lightness of a black step in a reflectance staircase was not altered by moving a white step from a remote to an adjacent location. Recently, E. Economou, S. Zdravkovic, and A. Gilchrist (2007) reported data supporting three additional predictions of the anchoring model (A. Gilchrist et al., 1999): 1) equiluminant incremental targets in staircase simultaneous lightness contrast stimuli appeared equally light; 2) the simultaneous lightness contrast effect was due mainly to the lightening of the target on the black surround; and 3) the strength of lightness induction was greatest for darker targets. We investigated similar stimuli using brightness/lightness matching and found, contrary to these reports, that: 1) the relative position of the steps in a luminance staircase significantly influenced their brightness/lightness; 2) equiluminant incremental targets in staircase simultaneous brightness/lightness contrast stimuli did not all appear equally bright/light; 3) an asymmetry due to a greater brightening/lightening of the target on the black surround was not general; and 4) darker targets produced larger effects only when plotted on a log scale. In addition, the ODOG model (B. Blakeslee & M. E. McCourt, 1999) did an excellent job of accounting for brightness/lightness matching in these stimuli.
Blakeslee
Barbara
B
Center for Visual Neuroscience, Department of Psychology, North Dakota State University, Fargo, ND 58108-6050, USA. barbara.blakeslee@ndsu.edu
Reetz
Daniel
D
McCourt
Mark E
ME
D015350:Contrast Sensitivity / Q000502:physiology*; D005556:Form Perception / Q000502:physiology; D006801:Humans; D008029:Lighting; D010775:Photic Stimulation; D011601:Psychophysics; D012160:Retina / Q000502:physiology*; D014796:Visual Perception / Q000502:physiology*