Slide 4

Characteristics of contrast adaptation in the visual cortex. The top left peristimulus histogram illustrates adaptation to a high contrast visual stimulus presented to the right eye. Adaptation to this stimulus also results in adaptation in the response in the left eye, even though this eye was not stimulated. In the right traces, the reverse is demonstrated. This result supports the proposal that contrast adaptation occurs in the cerebral cortex. The bottom graphs illustrate the contrast response function for a typical cortical cell before (left) and after (right, filled in circles) presentation of a high contrast stimulus. Note that adaptation to high contrast causes a rightward shift in the contrast response function curve, and a small compression.

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These results are from the following papers:

Maffei, L., Fiorentini, A., Bisti, S. (1973) Neural correlate of perceptual adaptation to gratings. Science 182: 1036-1038.

Sclar, G., Lennie, P., DePriest, D.D. (1989) Contrast adaptation in striate cortex of macaque. Vision Res. 29: 747-755.