PHYSIOLOGICAL INDUCTION IN HUMAN RETINA AS BASIS OF COLOR AND BRIGHTNESS CONTRAST

Abstract

From studies on the change in electrical excitability of the eye following a brief illumination, time constants characteristic of the basic retinal processes were detd. It was found that there were 3 kinds of processes in the fovea of trichromats, and the processes were named R, G, and B according to their time constants. The spectral loci of the processes R, G and B showed maxima at 590 m[mu], 550 rn[mu], and 460 m[mu], respectively. In the periphery of the retina, a new process, Y, with its maximum in the yellow part of the spectrum was found. The order of dominance of these processes, as measured by their maximum magnitudes, was as follows: G>R >B in the fovea, Y> B>G>R at 15[degree] from the fovea, B>Y>G>R at 25[degree] and 35[degree] from the fovea. At the fovea of color-blind subjects only 2 kinds of processes were found, of which one showed the same spectral sensitivity as the B process in trichromats, but the other was found to be different according to the kind of color-blindness.