OPPOSITE EFFECTS DEPENDING ON LEARNING AND MEMORY DEMANDS IN DORSOMEDIAL PREFRONTAL CORTEX LESIONED RATS PERFORMING AN OLFACTORY TASK

In this study, the functional properties of the dorsomedial prefrontal cortex (dmPFC) of the rat were examined in two olfactory tasks. In a successive cue olfactory discrimination task, dmPFC lesioned animals i mproved performance across sessions more rapidly than operated control animals. In an olfactory task using fixed interval training, animals with similar lesions were impaired. Both effects, although opposite, c an be explained by a temporal processing deficit. The present results seem to indicate that the dmPFC is required for timing, classified as part of non-declarative memory. As reference memory improved in the le sioned animals, the finding is that the dmPFC supports non-declarative memory and thus interacts with declarative memory in the long-term fo rmation of the associations between a particular stimulus (olfactory c ue) and particular responses.