Tracking the Hemodynamic Responses to Reward and Punishment in the Striatum

TLDR

The basal ganglia are a key component of reward processing circuitry, yet human studies have not yet characterized their response to isolated rewards as has been done in animal models. The study aimed to identify brain areas activated by reward presentation using an event‑related fMRI paradigm. Participants performed a card‑value guessing task with monetary incentives, receiving reward, punishment, or neutral feedback while fMRI recorded brain activity. The dorsal and ventral striatum showed differential activation, with reward feedback sustaining activity above baseline and punishment feedback reducing it below baseline.

Abstract

Research suggests that the basal ganglia complex is a major component of the neural circuitry that mediates reward-related processing. However, human studies have not yet characterized the response of the basal ganglia to an isolated reward, as has been done in animals. We developed an event-related functional magnetic resonance imaging paradigm to identify brain areas that are activated after presentation of a reward. Subjects guessed whether the value of a card was higher or lower than the number 5, with monetary rewards as an incentive for correct guesses. They received reward, punishment, or neutral feedback on different trials. Regions in the dorsal and ventral striatum were activated by the paradigm, showing differential responses to reward and punishment. Activation was sustained following a reward feedback, but decreased below baseline following a punishment feedback.