Neural correlates to action and rewards in the rat posterior cingulate cortex

To investigate the involvement of the posterior cingulate cortex in reward-based learned actions, we examined its neuronal activities in rats that were trained in a delayed stimulus-response association task. Of the 344 neurons recorded, 178 responded during licking a spout to acquire rewards (a sucrose solution or intracranial self-stimulation). Of these 178 reward-responsive neurons, 80 responded exclusively during licking to acquire sucrose solution, and 20 during licking to acquire intracranial self-stimulation, with 37 of these 100 neurons displaying differential correlation to individual licking on the basis of the reward type. The present results and comparison with previous studies on the anterior cingulate cortex suggest that the posterior cingulate cortex is involved in the monitoring or storage of action-reward outcome association. NeuroReport 16:949-953 (c) 2005 Lippincott Williams & Wilkins.