Abstract

The visual system requires error-correcting mechanisms that can cope with internal changes (e.g., cell death, lens yellowing). An error correcting mechanism might examine the statistical properties of the visual input and recalibrate if the input is inconsistent with normal visual stimulation.¹ For example, on average, color and orientation are uncorrelated in natural stimuli. A correlation might indicate a change internal to the visual system (e.g., damage to one input to an orientationally-tuned, color opponent mechanism). In a standard McCollough effect (McE) paradigm, Ss adapt to red vertical and green horizontal stimuli, making white verticals appear greenish and white horizontals appear reddish. Adaptation to red vertical alone also produces a McE; however, adaptation to red vertical and red horizontal produces little or no McE. In all three cases, orientationally-selective color mechanisms are strongly stimulated and one might expect similar effects of adaptation. However, in the last there is no correlation between color and orientation and no stimulus for error-correction. These restrictions on the McE act to prevent erroneous recalibration under normal viewing conditions.²

© 1990 Optical Society of America