Disruption of the connections between the mediodorsal and sulcal prefrontal cortices alters the associability of rewarding medial cortical stimulation to place and taste stimuli in rats.

This study involved 2 tests of conditioned reward with self-stimulation (SS) of the prefrontal cortex. In Experiment 1, rats were tested for a conditioned taste preference (CTP) induced by pairing a novel flavor with SS of the medial prefrontal cortex (MC). Normal rats displayed a CTP. Rats with bilateral cuts of the connections between the MC and sulcal prefrontal cortex (SC) did not show a CTP. In Experiment 2, similar cuts had no effect on the ability of SC SS to promote a CTP, showing that the cuts spare the ability to learn a CTP. In Experiment 3, rats were tested for a conditioned place preference by pairing MC SS with environmental cues. Lesioned rats, but not intact rats, had a CPP. Results suggest the presence of prepotent relations, dependent on intrinsic prefrontal connections, between the rewarding effects of prefrontal stimulation and distinct sensorimotor domains.