Topic: action-gradient

Task acquisition in the brain relies on both reward-based and error-based learning (RBL, EBL), yet how the brain brings these two learning signals together remains elusive. Here, we build on the traditional view that dopamine (DA) projections within the basal ganglia (BG) drive RBL via reinforcement learning, while the cerebellum (CB) supports EBL via supervised learning. In doing so, we introduce a novel learning framework that combines DA-driven RBL with CB-driven EBL. Specifically, we reformulate the traditional RBL and EBL synaptic weight updates in terms of a shared ‘action-gradient’ spac