A: Drawings showing the extension of the ventral hippocampal damage induced by neonatal ibotenic acid observed in adulthood. Gray and dark areas indicate maximal and minimal extents of damage, respectively. B: Coronal Nissl stained sections showing the ventral hippocampus of a sham rat (top, Sham) and a typical neonatal ventral hippocampal lesion (bottom, NVHL), characterized by cell loss (thick arrows), and enlarged ventricles (asterisks).