Sulpiride infused into the nucleus accumbens posttraining impairs memory of spatial water maze training.

A variety of nucleus accumbens (NA) manipulations induce deficits in spatial learning and memory tasks. It is not known, however, if these deficits reflect influences on memory or on other processes affecting performance. The experiments in this article were undertaken to examine the involvement of the NA in memory consolidation in a spatial task. Rats were given 1 training session in a spatial water maze immediately followed by intra-NA infusions of sulpiride or saline vehicle. A probe test 2 days later revealed an impairing effect of sulpiride on several retention measures. Sulpiride infused into the NA either 2 hr posttraining in the spatial task or immediately posttraining in a cued water maze task did not affect retention performance. These findings suggest that the impairing effects of immediate posttraining sulpiride in the spatial task are due to interference with spatial water maze-specific consolidation processes involving the NA.