Bilateral Effects on Retinal Shielding Pigments During Monocular Photic Stimulation in the Crayfish, Procambarus

Abstract

Bilateral light adaptation of distal retinal shielding pigments was observed a few minutes after 60 min of sustained photic stimulation (2.69 Cd/m2) of a single eyestalk of the dark-adapted crayfish. Pigment migration was observed in intact animals as a diminution of eye glow area and electroretinogram amplitude, and was confirmed in sectioned material. The effect upon the contralateral eye was abolished by surgical bisection of the cerebral ganglion. It is suggested that the mechanism involved in the bilateral effect may be responsible for the mutual entrainment of ERG circadian rhythms of both eyes.