Retinal induction in various regions of human retina.

Abstract

By the method of electro-stimulation, retinal induction was measured at various parts of the human retina. 1. The magnitude of retinal induction was found greatest at about 10° from the fovea. This fact might be correlated with the psychological fact that color contrast can most easily be perceived in the para-foveal region of the retina. 2. Red and green lights were found more effective in producing retinal induction than yellow and blue lights. 3. In measurements of retinal induction two photic stimuli are used, i.e., a colored light preceding a white test light. The intensity of retinal induction was shown to be independent of the intensity and the duration of the white test light, but determined by those of the inducing colored light. This law holds good for both foveal and peripheral vision. The authors are indebted to Prof. K. Motokawa for his invaluable advice and encouragement.