THE INFLUENCE OF DEPICTED ILLUMINATION ON BRIGHTNESS

The striking illusions produced by simultaneous brightness contrast ge nerally are attributed to the center-surround receptive field organiza tion of lower order neurons in the primary visual pathway. Here we sho w that the apparent brightness of test objects can be either increased or decreased in a predictable manner depending on how light and shado w are portrayed in the scene. This evidence suggests that perceptions of brightness are generated empirically by experience with luminance r elationships, an idea whose implications we pursue in the accompanying paper.