DURATION OF RETROGRADE AMNESIA AS A FUNCTION OF ELECTROCONVULSIVE SHOCK INTENSITY

Effects of different ECS intensities on the duration of retrograde amnesia in rats following single trial avoidance learning in a step-down situation were studied. High intensity ECS produced an amnesia which lasted throughout the longest retention interval tested (48 hr). Low intensity ECS only produced a temporary amnesia. Retention was depressed at 1 hr following footshock, but had returned 23 hr later. The effectiveness of ECS appears to depend not only on the time of administration following learning, but on the intensity of the interference. © 1969.