Filling-in afterimage colors between the lines.

It is known that when a colored surface is viewed for some time and a blank screen is presented afterwards, an afterimage can be perceived in the complementary color. Color appearances in afterimages are due to adaptation of retinal cones and they are especially vivid when contours, presented after the adapting image, coincide with the blurred edges of the afterimage [1]. We report here that one and the same colored stimulus can induce multiple, differently colored afterimages, and that colored afterimages can also be perceived at regions that were not adapted to color. The observed filling-in of afterimage colors strongly depends on contours presented after the colored stimulus, revealing color-contour interactions that resemble filling-in of 'real' colors.