Environmental control of ECS-produced retrograde amnesia in goldfish

Abstract

The retrograde amnestic effect of ECS can be enhanced by exposing the goldfish to the intertrial environment for 25 mm just prior to administration of the ECS. As the interval between training and the ECS is increased, the amnesm produced by the environment-ECS interaction takes longer to develop. The environment-dependent effects of ECS relate to those of other amnestic agents which have previously been described. Amnesia Memory consolidation Shock avoidance Conditioning goldfish Electroconvulsive shock

Effects of electroconvulsive shock and puromycin on operant responding in goldfish

“…Aversive effects of a single ECS, as typically used in experiments on the amnestic effects of ECS in the laboratory rat have been described [21]. Stimulus effects of amnestic agents could be responsible for environment-dependent amnesia in goldfish [7]. The present demonstration that a single ECS treatment has behavioral effects which can be attributed to the stimulus properties of the treatment supports this possibility.…”

“…But we cannot rule out the possibility that the interference represents a memory loss. Memory activated during a session might be vulnerable to interference by an immediate postsession ECS [7,13,22]. We propose, however, that the present results show two effects of ECS neither of which entails a loss of memory.…”

“…The behavioral effects of ECS and tail shock, however, may not be identical. For instance, a tail shock does not duplicate the amnesic effect of ECS in goldfish [7].…”

“…A series of experiments with goldfish has shown, however, that the amnesia produced by ECS and puromycin depends not only on the time elapsed since the learning experience, but also on the stimulus environment of the animal just prior to treatment [4,7,11 ]. In fact, retention deficits can be produced long after memory storage is presumably complete if the appropriate environmental conditions are instituted before treatment.…”

Branchial ventilation rates of cataleptic goldfish (Carassius auratus) and the effects of light and electric shock

“…reported that ECS can produce retrograde amnesia of classically conditioned inhibition of ventilation rates (opercula beats) in cataleptic goldfish. Prior experiments in noncataleptic fish showed that ECS can induce amnesia of an active avoidance response [1,2]. That ECS can block retention of automatic and behavioral responses suggested that both types of responses could be mediated by common memory processes.…”