Response Curve of the Yellow Receptors of the Human Fovea

Abstract

THE micro-stimulation apparatus¹ has been used recently for studying the shapes of the response curves of some of the receptors which take part in human foveal colour vision. It will be remembered that Granit found evidence for seven kinds of ‘modulator’ in the retinæ of such animals as frogs, snakes and rats, which had maximum responses at the following approximate wave-lengths: 6000, 5800, 5400, 5200, 5000, 4600 and 4400 angströms. All these had narrow response curves. In the cat, on the other hand, the response curves appeared to be wider, having legs which were farther apart. Particularly was this the case with the ‘modulators’ produced from ‘dominators’ after the retina had been exposed to red, to green, or to blue lights.