Primary Color - Psychological Primaries

Psychological Primaries

Main article: Opponent process. See also: Natural Color System, Unique hues

The opponent process is a color theory that states that the human visual system interprets information about color by processing signals from cones and rods in an antagonistic manner. The three types of cones have some overlap in the wavelengths of light to which they respond, so it is more efficient for the visual system to record differences between the responses of cones, rather than each type of cone's individual response. 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. The particular colors considered by an observer to be uniquely representative of the concepts red, yellow, green, blue, white, and black might be called "psychological primary colors", because any other color can be described in terms of some combination of these.