The orbitofrontal cortex and reward

The primate orbitofrontal cortex contains the secondary taste cortex, in wh ich the reward value of taste is represented. It also contains the secondar y and tertiary olfactory cortical areas, in which information about the ide ntity and also about the reward value of odors is represented. The orbitofr ontal cortex also receives information about the sight of objects and faces from the temporal lobe cortical visual areas, and neurons in it learn and reverse the visual stimulus to which they respond when the association of t he visual stimulus with a primary reinforcing stimulus (such as a taste rew ard) is reversed. However, the orbitofrontal cortex is involved in represen ting negative reinforcers (punishers) too, such as aversive taste, and in r apid stimulus-reinforcement association learning for both positive and nega tive primary reinforcers. In complementary neuroimaging studies in humans i t is being found that areas of the orbitofrontal cortex (land connected sub genual cingulate cortex) are activated by pleasant touch, by painful touch, by rewarding and aversive taste, and by odor. Damage to the orbitofrontal cortex in humans can impair the learning and reversal of stimulus-reinforce ment associations, and thus the correction of behavioral responses when the se are no longer appropriate because previous reinforcement contingencies c hange. This evidence thus shows that the orbitofrontal cortex is involved i n decoding and representing some primary reinforcers such as taste and touc h: in learning and reversing associations of visual and other stimuli to th ese primary reinforcers: and in controlling and correcting reward-related a nd punishment-related behavior, and thus in emotion.