Multiple representations of belief states and action values in corticobasal ganglia loops.

Reward-related neural activities have been found in a variety of cortical and subcortical areas by neurophysiological and neuroimaging experiments. Here we present a unified view on how three subloops of the corticobasal ganglia network are involved in reward prediction and action selection using different types of information. The motor/premotor-posterior striatum loop is specialized for action-based value representation and movement selection. The orbitofrontal-ventral striatum loop is specialized for object-based value representation and target selection. The lateral prefrontal-anterior striatum loop is specialized for context-based value representation and context estimation. Furthermore, the medial prefrontal cortex (MPFC) coordinates these multiple value representations and actions at different levels of hierarchy by monitoring the error in predictions.