Dual credit assignment processes underlie dopamine signals in a complex spatial environment.

ABSTRACT: Dopamine in the nucleus accumbens helps motivate behavior based on expectations of future reward ("values"). These values need to be updated by experience: after receiving reward, the choices that led to reward should be assigned greater value. There are multiple theoretical proposals for how this credit assignment could be achieved, but the specific algorithms that generate updated dopamine signals remain uncertain. We monitored accumbens dopamine as freely behaving rats foraged for rewards in a complex, changing environment. We observed brief pulses of dopamine both when rats received reward (scaling with prediction error), and when they encountered novel path opportunities. Furthermore, dopamine ramped up as rats ran towards reward ports, in proportion to the value at each location. By

SUBMITTER: Krausz TA 

PROVIDER: S-EPMC10054934 | biostudies-literature | 2023 Mar

REPOSITORIES: biostudies-literature