PRENATAL EXPOSURE TO ETHANOL DISRUPTS SPATIAL MEMORY - EFFECT OF THE TRAINING-TESTING DELAY PERIOD

The present study investigated how variations in the period of delay b etween training and testing in the Morris water maze task affect the u se of spatial memory in adult rats that were prenatally exposed to eth anol. Previous results utilizing the Morris water maze task have shown that prenatal, or early postnatal, exposure to ethanol produces defic its in the use of spatial memory, a type of memory that is dependent o n an intact hippocampus. However, in these prior studies the delay per iod between the training of animals and the testing of spatial memory is typically fixed at only 1 day. In the current study, which utilized a revised training procedure within the Morris water maze task, the p eriod of delay between training and testing was altered such that it w as either 1 day or 3 days. Following the 3-day delay, different levels of prenatal exposure to ethanol impaired the use of spatial memory. I n contrast, following the 1-day delay, prenatal exposure to ethanol fa iled to impair the us, of spatial memory. The present study thus shows that prenatal exposure to ethanol differentially affects spatial memo ry in the Morris water maze task depending on the period of delay betw een training and testing. (C) 1998 Elsevier Science Inc.