SEX-DIFFERENCES IN PERFORMANCE IN THE MORRIS WATER MAZE AND THE EFFECTS OF INITIAL NONSTATIONARY HIDDEN PLATFORM TRAINING

Sex differences in rats' performance on a stationary hidden-platform t ask (spatial task) in the Morris water maze and the effects of initial nonstationary hidden platform training (NSP training) were examined. The NSP training was designed to familiarize rats with the general req uirements of the water-maze task without providing spatial information . NSP training led to faster acquisition and improved retention of the subsequent spatial task in both males and females. There was a sex di fference favoring males on acquisition and retention of the spatial ta sk only in rats that had not received previous NSP training. Moreover, there was an apparent reversed sex difference favoring females on som e measures of spatial performance in NSP-trained rats. These results s uggest that performance on the water-maze task, including the expressi on of sex differences, can be altered by previous familiarization with nonspatial aspects of the task.