Distributed Population Coding and Memory Consolidation in the Cerebellar Cortex and Dentate Nucleus.

The cerebellum contributes to associative learning, yet how cortical and nuclear populations interact during memory formation remains unclear. We recorded single neurons from Purkinje cells (PCs) in Crus I/II and from the dentate nucleus (DN) in monkeys learning a visuomotor association. Both populations encoded the association in a temporally distributed manner spanning stimulus onset to movement. Once learning was consolidated, DN population activity preceded that of PCs, suggesting a progressive transfer of information from the cerebellar cortex to the nuclei, where long-term memory traces are stabilized. Spike-time analyses revealed that temporal regularity and bursts provide coding dimensions independent of firing rate and dynamically modulated across learning. These temporal features likely facilitate plasticity during acquisition and stabilize network dynamics after consolidation. Together, the results identify the dentate nucleus as an active site of memory consolidation and highlight distributed, ensemble-level mechanisms underlying cerebellar learning and predictive control.