Striatal dopamine pulses follow a temporal discounting spectrum

Abstract

The striatum is critical for making decisions based on predictions of future reward. These predictions can be updated by brief pulses of dopamine, encoding reward prediction errors. However, it is unclear how this mechanism handles the need to generate predictions over multiple time horizons: from seconds or less (if singing a song) to potentially hours or more (if hunting for food). Here we monitor and model dopamine pulses across distinct striatal subregions, and find that these reflect predictions over distinct temporal scales. Dopamine dynamics systematically accelerated from ventral to dorsal-medial to dorsallateral striatum, in the tempo of their spontaneous fluctuations, their integration of prior rewards, and their discounting of future rewards. In this way parallel striatal circuits can achieve a more comprehensive set of value computations, to guide a broad range of reward-related behaviors.