Tonic dopamine and biases in value learning linked through a biologically inspired reinforcement learning model.

ABSTRACT: A hallmark of various psychiatric disorders is biased future predictions. Here we examined the mechanisms for biased value learning using reinforcement learning models incorporating recent findings on synaptic plasticity and opponent circuit mechanisms in the basal ganglia. We show that variations in tonic dopamine can alter the balance between learning from positive and negative reward prediction errors, leading to biased value predictions. This bias arises from the sigmoidal shapes of the dose-occupancy curves and distinct affinities of D1- and D2-type dopamine receptors: changes in tonic dopamine differentially alters the slope of the dose-occupancy curves of these receptors, thus sensitivities, at baseline dopamine concentrations. We show that this mechanism can explain biased value le

SUBMITTER: Romero Pinto S 

PROVIDER: S-EPMC12350682 | biostudies-literature | 2025 Aug

REPOSITORIES: biostudies-literature