Surround configuration and cone dark adaptation

Parafoveal cone dark adaptation curves were recorded following bleaches of various spatial configurations. Bleaching patterns having a contour in the neighborhood of the test stimulus gave dark adaptation curves similar to those after uniform bleaching patterns. This is evidence against an explanation of the sensitization observed in cone dark adaptation in terms of central perceptual interference or masking of the test spot by nearby contours, and suggests that the total amount of surround light, and not its spatial distribution, is what is important.