Temporary occlusion of the central retinal artery in rhesus monkeys changes the oscillatory potentials and the b-wave amplitude in electroretinogram and the slow oscillations in electrooculogram. Reduction of the amplitudes of the oscillatory potentials is the earliest sign that can be observed. The cone-dependent b-wave is more sensitive than the rod-dependent b-wave. The earliest change in EOG is an alteration of the time course of the light induced slow oscillation. The peak latency is prolonged and return to baseline is delayed.