{D}-Cycloserine: Effects on Long-term Retention of a Conditioned Response and on Memory for Contextual Attributes

Publication Title

Neurobiology of Learning and Memory

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d-Cycloserine(DCS), memory, saline subjects, stimulus attributes


Cognitive Psychology | Psychology


{D}-Cycloserine (DCS), a partial agonist of the glycine recognition site of the N-methyl-D-aspartate (NMDA) receptor, has beneficial effects on learning and memory. In order to investigate its potential to influence learning and memory of both the response and the stimulus attributes of training, 20 male rats were trained in 1-trial inhibitory avoidance task following an acute intraperitoneal/ly (ip) injection of DCs or an equal volume of saline. Memory for stimulus attributes was measured through testing involving a context shift paradigm, in which Ss are tested in either the environment of training or a different one. Good memory for the contextual attributes of training is indicated by poor performance in the alternate context. Retention was assessed either 1, 7, or 14 days after training. At 1 day, Saline Ss were affected by a change in context, while DCS Ss were not. In Ss tested 1 week following training, Saline Ss were no longer affected by a change in context, in that they performed the avoidance response in both contexts. Finally, Saline Ss demonstrated the context shift rebound at 14 days, while DCS Ss per formed equivalently in both contexts. Taken together, these data suggest that DCS may enhance retention of fear and slow the forgetting of stimulus attributes.