PREFRONTAL CORTEX AND WORKING-MEMORY FOR SPATIAL RESPONSE, SPATIAL LOCATION, AND VISUAL OBJECT INFORMATION IN THE RAT

In the first experiment, rats were trained on a working memory task fo r a spatial response {right-left turn} information using a delayed mat ching-to-sample procedure. Following lesions of the medial prefrontal cortex (MPF), which includes anterior cingulate and medial precentral cortex, there was a profound working memory deficit even at the shorte st delay In the second experiment, rats were trained on a working memo ry task for spatial location information using a delayed matching-to-s ample procedure. Following lesions of the MPF. there was only a mild w orking memory deficit, whereas following dorsal hippocampal lesions th ere was a profound working memory deficit even at the shortest delay. In the third experiment, rats were trained on a working memory task fo r visual object information using a delayed nonmatching-to-sample proc edure. Following lesions of the MPF, there were no working memory defi cits, whereas following lesions of the prelimbic and infralimbic corte x there was a profound working memory deficit even at the shortest del ay. The results suggest that different neural subregions of the prefro ntal cortex mediate working memory for specific attribute information.