Information Theoretic Aspects of Color Signal Processing in the Visual System

Since its inception, information theory has been a major conceptual element of modern communication theory. It has also served to focus thinking about signal processing in the nervous system. Here, it is applied to provide a logical mathematical rationale for early color signal processing by the visual system. The analysis is made within the context of the relevant visual physiology, which includes photon absorption, photopigment isomerization and regeneration, translation of isomerization rate into membrane potential, and the opponent colors transformation. Results from information and communication theory are used to detail how the information obtained by the photoreceptor array of the retina could most efficiently be processed in the context of the known physiologic limitations. The resulting model is applied to an analysis of some of the classic experiments of color vision, including those of increment threshold and hue cancellation, and provides an explanation for the opponent nature of color vision.