RETINAL MECHANISMS FOR CHROMATIC AND ACHROMATIC VISION

Certain results of our recent studies on what we call the graded photopic response (g.p.r.) of the retina have been presented elsewhere.' However, that presentation was limited to a description of the electrophysiological experiments and their results. Our purpose here is to discuss these results in relation to other similar studies2-ls and to attempt to fit them into the framework of present knowledge of experimental human and animal psychology. This paper first describes the general characteristics of the g.p.r., and then discusses a number of observations in neurophysiological terms. Experimental animal psychology studies on the performance of the visual system of