Medial prefrontal cortex lesions cause deficits in a variable-goal location task but not in object exploration

The role of the medial prefrontal cortex (PFC) in goal-directed behavior wa s examined in rats with aspiration lesions. In Experiment 1, PFC lesions re sulted in an impaired ability to relearn the location of a behaviorally def ined goal arm of a plus-maze after it was moved from an initially fixed pos ition. Lesioned rats also exhibited a significantly greater degree of perse veration compared with control animals. Experiment 2 was an object explorat ion task in which rats had to respond to a change in the layout of the envi ronment. PFC-lesioned rats performed identically to controls, therefore dem onstrating that the deficits observed in Experiment 1 did not result from a deficit in the ability to explore the environment. The results are discuss ed in terms of several competing, but not mutually exclusive explanations o f the role of the PFC in navigation and spatial representation.