Anterograde and retrograde effects of electroconvulsive shock and of puromycin on memory formation in the goldfish.

Electroconvulsive shock [ECS] or puromycin administered prior to training did not significantly impair acquisition of shock-avoidance in goldfish. Significant retention deficits are observed on retraining 72 hr later in groups of fish that received ECS 2.5, 1 or 0.5 hr before training as well as in groups that received ECS 0, 4 or 24 hr after training. Puromycin produces significant retention deficits on retraining when given 24, 16, 8, 4 or 0 hr prior to, or 0 or 0.25 hr following training. A temporal course of development of the retention deficit that has been seen with puromycin was not observed with ECS as the deficit was maximal at the earliest trainretrain interval examined. ECS administered before both training and retraining did not relieve the deficit. Since performance was not diminished in fish retrained just after ECS, it appears that this proactive effect of ECS reflects disruption of memory rather than state-dependent learning.