Reward processing in the human brain. Insights from fMRI

Reward processing engages diverse brain regions, including multiple prefrontal regions and the basal ganglia (particularly the multifaceted striatum). Corticostriatal circuits are involved in computation of subjective value for experienced rewards, leading to a valuation signal that can be used to guide future decisions via reinforcement-learning mechanisms. In recent years, an explosion of neuroimaging research has replicated and extended findings from a rich body of animal literature on basic brain reward systems to probe how such systems are modulated by more complex processes that typically influence goal-directed behavior in human society. The goal of this chapter is to discuss the integration of neuroimaging studies of reward processing, with emphasis on cortical-striatal circuits involved in goal-directed behavior and the valuation of reward-related information. Neuroimaging research highlights functional subdivisions within components of this corticostriatal circuitry. Reward processing can be modulated by a number of additional factors, including magnitude of reward, risk, time, and social context. Furthermore, the chapter highlights how cortical-striatal circuits and valuation signals can be modulated by the presence of more complex factors such as risk, time, and social context. Important directions for future research include the study of the complex modulation of reward processing by social factors, as well as processing of aversive information that can also modulate behavior.