Cerebellar Dentate Connectivity Across Adulthood: A Large-Scale Resting State Functional Connectivity Investigation

Abstract

Cerebellar contributions to behavior in advanced age are of great interest and importance, given its role in motor and cognitive performance. There are differences and declines in cerebellar structure in advanced age, and cerebellar resting state connectivity is decreased. However, the work on this area to date has focused on the cerebellar cortex. The deep cerebellar nuclei provide the primary cerebellar inputs and outputs to the cortex, as well as the spinal and vestibular systems. In both human and non-human primate models, dentate networks can be dissociated such that dorsal region is associated with the motor cortex, while the ventral aspect is associated with the prefrontal cortex. However, whether or not dentato-thalamo-cortical networks differ across adulthood remains unknown. Here, using a large adult sample (n=591) from the Cambridge Center for Ageing and Neuroscience, we investigated dentate connectivity across adulthood. First, we replicated past work showing dissociable resting state networks in the dorsal and ventral aspects of the dentate. Second, in both seeds, we demonstrated connectivity decreases with age, indicating that connectivity differences extend beyond the cerebellar cortex. This expands our understanding of cerebellar circuitry in advanced age, and further underscores the potential importance of this structure in age-related performance differences.

Reduced cerebello-cerebral functional connectivity correlates with disease severity and impaired white matter integrity in Friedreich ataxia

“…Three bilateral cerebellar cortical regions-of-interest (ROI) were defined for each participant: (i) anterior lobe (lobules I-V), (ii) superior posterior lobe (lobules VI-VII) and (iii) inferior posterior lobe (lobules VIII-IX). Two dentate nucleus ROIs were additionally defined using 2 mm radial spheres centred on MNI coordinates defined by previous literature [29,36]: (i) dorsal seed: x = 12, y = − 57, z = − 30 and (ii) ventral seed: x = 17, y = − 65, z = − 35. The dentate seeds were defined in the right hemisphere only.…”