Differential Contributions of Ventral Striatum Subregions to the Motivational and Hedonic Components of the Affective Processing of Reward.

The ventral striatum is implicated in the affective processing of reward, which can be divided into a motivational and a hedonic component. Here, we examined whether these two components rely on distinct neural substrates within the ventral striatum in humans (11 females and 13 males). We used a high-resolution fMRI protocol targeting the ventral striatum combined with a pavlovian-instrumental task and a hedonic reactivity task. Both tasks involved an olfactory reward, thereby allowing us to measure pavlovian-triggered motivation and sensory pleasure for the same reward within the same participants. Our findings show that different subregions of the ventral striatum are dissociable in their contributions to the motivational versus the hedonic component of the affective processing of reward. Parsing the neural mechanisms of the interplay between pavlovian incentive and hedonic processes may have important implications for understanding compulsive reward-seeking behaviors such as addiction, binge eating, or gambling.