Hyperactive Cerebellum in Alzheimer’s Disease

Motivation: Cerebellar involvement in Alzheimer’s disease (AD) has not been studied to the extent that cortical neuropathological changes have been. Historical and recent histopathological literature demonstrates cerebellar AD pathology while functional investigations have demonstrated disrupted intrinsic cortical – cerebellar connectivity in AD. Goal(s): Investigate metabolic activity and functional connectivity of the cerebellum with the default mode network, dorsal attention network, and primary olfactory cortex. Approach: Characterizing the cerebellum’s metabolic activity using 18F-fluorodeoxyglucose positron data from the Alzheimer’s Disease Neuroimaging Initiative. Results: In contrast to known parietal and temporal lobe FDG hypo-metabolism in AD, significant FDG hyper-metabolism was found in the cerebellum. Impact: Results show that resting state functional connectivity of cerebellar regions (that show hyper FDG metabolic activity) is impaired across brain-wide networks. Future work focusing on inhibitory control of the cerebellum as a potential pathway of AD pathogenesis is warranted.