Permanence of a long temporal gradient of retrograde amnesia induced by electroconvulsive shock

Abstract

Electroconvulsive shock (ECS) was administered to mice 10 sec, 120 sec, and 3 h after training in a passive avoidance task. Subgroups were retested at 24 h, 48 h, 72 h, 1 week, and 4 weeks. A temporal gradient of retrograde amnesia was produced, with ECS still being effective even when given 3 h after training. The gradient was maintained over all retest times. No evidence of recovery could be detected.