Prediction of immediate and future rewards differentially recruits cortico-basal ganglia loops

Tanaka, S.C. et al. (August 2004). Prediction of immediate and future rewards differentially recruits cortico-basal ganglia loops. Nature Neuroscience, Volume 7, Number 8, 887-893.

Curiously, lesions in the nucleus accumbens in rats result in a tendency to choose small immediate rewards over larger future rewards. And low activity in the central serotonergic system is also associated with impulsive behavior in humans. This article argues that the lateral orbit-frontal cortex (OFC) takes on the role of predicting immediate rewards, while the dorsolateral prefrontal cortex (dlPFC), dorsal pre-motor cortex (dMC), and inferior parietal cortex (IPC) are involved in prediction of future outcomes. Therefore, different sub-loops of the cortico-basal ganglia network are specialized for reward prediction at different time scales. The last piece of the puzzle, the dorsal raphe nucleus, is thought to use serotonin influence to control the effective time scale of reward prediction, allowing flexible selection of a relevant time-scale appropriate for the task at the time of decision-making.