The Mechanism of Spatial Induction in the Retina

Abstract

By the method of electrostimulation, the time course of development of indirect retinal induction was investigated. Indirect induction is a physiological correlate of simultaneous contrast.
1. Indirect induction appears with a latent period of 60 msec. in the immediate neighborhood of the retinal part illuminated by colored light.
2. The intensity of indirect induction increases with the lapse of time after removal of colored light, and reaches a constant level in about 300 msec.
3. At various distances from the area illuminated by colored light, development of indirect induction was measured, and it was found that the development is delayed in proportion to the distance. From this relation the velocity of spread of indirect induction was determined. The velocity was found to be 1.69mm./sec. in the retina in complete agreement with the value determined by Motokawa with another method.