Episodic memory decline in aging is usually explained by cortico-hippocampal dysfunction, but the cerebellum may also shape memory performance through its interactions with association cortex. We examined task-evoked cerebellar organization and cerebellar–cerebral interactions in fMRI during episodic memory in a large cohort of cognitively normal older adults with follow-up.

We identified three cerebellar networks with distinct memory relevance: a bilateral lobule VI / Crus I mnemonic-monitoring network, a right Crus I/II default-mode-aligned network and a right lobule VIIb/VIIIa evidence-evaluation network. Their dynamic functional connectivities with cerebral cortex differentiated memory-performance groups and predicted longitudinal slowing in retrieval.

These findings suggest that memory resilience in older adults depends on preserved temporal coordination between specialized cerebellar networks and distributed cortical systems.