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Publisher Summary This chapter discusses a direct comparison of prefrontal cortex (PFC) and hippocampal area (HPC) by presenting selected results of a series of recent experiments pertaining possible dissociable roles of PFC and HPC in a variety of rat models of learning, memory, and attention. Data pertaining to the involvement of the PFC and the HPC in different cognitive processes in rats shows that indeed both the PFC and the HPC of the rat are essential brain structures for learning, memory, and attention processes. However, even though lesions of these structures have been shown to disrupt performance of similar if not the same behavioral paradigms, this is not to say that their roles in these processes are similar; both qualitative and quantitative differences in lesion effects can be obtained with direct comparisons, using adequate behavioral procedures. Results of such comparisons show that lesions of the HPC disrupt spatial learning, working memory and selective attention, whereas lesions of the PFC disrupt working memory, behavioral flexibility, and sustained attention.

Publisher Summary This chapter describes the role of the prefrontal cortex of the rat in learning and decision making. Depending on the authors reviews of prefrontal cortex (PFC) functions in rats have provided lists of behavioral deficiencies following damage of the PFC. They include deficient performance in various delay-type tasks, spatial tasks, inhibition, attention, along with abnormalities in social behavior. When rats with PFC damage are examined for their spatial learning skills in a Morris water maze, no impairments in spatial learning could be detected; however, when the task was changed from an allocentric one to a visual-cued one, rats with damage of the medial PFC were initially impaired. It is assumed that with prefrontal damage, it was more difficult to shift between tasks with different task demands. Evidence supporting this assumption has been obtained, when rats are trained either in a cheeseboard task, or a visual-cued version of that task. Transient inactivation of the medial PFC did not interfere with task acquisition. However, such an inactivation impaired learning when the rats were switched from one version of the task to the other one. It is tempting to relate these findings with the well-known deficiencies described in humans with PFC damage.