These effects are accompanied by neural adaptations in the occipital lobe of the brain that function similar to color balance adjustments in photography. These adaptations attempt to keep vision consistent in dynamic lighting. Viewing a uniform background while these adaptations are still occurring will allow an individual to see the afterimage because localized areas of vision are still being processed by the brain using adaptations that are no longer needed. The Young-Helmholtz trichromatic theory of color vision postulated that there were three types of photoreceptors in the eye, each sensitive to a particular range of visible light: short-wavelength cones, medium-wavelength cones, and long-wavelength cones. Trichromatic theory, however, can not explain all afterimage phenomena. Specifically, afterimages are the complementary hue of the adapting stimulus, and trichromatic theory fails to account for this fact.The failure of trichromatic theory to account for afterimages indicates the need for an opponent-process theory such as that articulated by Ewald Hering (1878) and further developed by Hurvich and Jameson (1957). The opponent process theory states that the human visual system interprets color information by processing signals from cones and rods in an antagonistic manner. The opponent color theory suggests that there are three opponent channels: red versus green, blue versus yellow, and black versus white. Responses to one color of an opponent channel are antagonistic to those of the other color. Therefore, a green image will produce a magenta afterimage. The green color fatigues the green photoreceptors, so they produce a weaker signal.
The "afterimage on empty shape" effect is related to a class of effects referred to as contrast effects.In this effect, an empty (white) shape is presented on a colored background for several seconds. When the background color disappears (becomes white), an illusionary color similar to the original background is perceived within the shape. The mechanism of the effect is still unclear, and may be produced by one or two of the following mechanisms:

During the presentation of the empty shape on a colored background, the colored background induces an illusory complementary color ("induced color") inside the empty shape. After the disappearance of the colored background an afterimage of the "induced color" might appear inside the "empty shape". Thus, the expected color of the shape will be complementary to the "induced color", and therefore similar to the color of the original background. After the disappearance of the colored background, an afterimage of the background is induced. This induced color has a complementary color to that of the original background. It is possible that this background afterimage induces simultaneous contrast on the "empty shape". Simultaneous contrast is a psychophysical phenomenon of the change in the appearance of a color (or an achromatic stimulus) caused by the presence of a surrounding average color (or luminance).