Cerebellar dentate nucleus functional connectivity with cerebral cortex in Alzheimer's disease and memory: a seed-based approach

Alzheimer Disease (AD) is a chronic neurodegenerative disorder characterized by specific patterns of grey and white matter damage and cognitive/behavioral manifestations. The cerebellum has also been implicated in the pathophysiology of AD. Since the cerebellum is known to have strong functional connectivity (FC) with associative cerebral cortex regions, it is possible to hypothesize that it is incorporated into intrinsic FC networks relevant to cognitive manifestation of Alzheimer disease. In the present study the cerebellar Dentate Nucleus (DN), the largest cerebellar nucleus and the major output channel to cerebral cortex, was chosen as the regions of interest to test potential cerebello-cerebral FC alterations and correlations with patients’ memory impairment in a group of AD patients. Compared to controls, AD patients showed an increase in FC between the DN and regions of the lateral temporal lobe. This study demonstrates that lower memory performances in AD may be related to altered FC within specific cerebello-cortical functional modules, thus suggesting the cerebellar contribution to AD pathophysiology and typical memory dysfunctions.