Delineation of cerebrocerebellar networks with MRI measures of functional and structural connectivity

Abstract

In humans, resting-state functional connectivity MRI (fcMRI) allows precise in vivo delineation of the neocerebellum’s participation in well-segregated, nonmotor intrinsic connectivity networks (ICNs). These data reveal that the neocerebellum participates in several ICNs, including the default mode network (lobule IX), the salience network (lobule VI), and the right and left executive networks (crus I and II). Additionally, fcMRI permits an anatomical parcellation of the neocerebellum based on its specific functional links with the associative cortex. Lobules V, VII, IX, and especially crus I and II constitute a supramodal cognitive zone specifically interconnected with prefrontal, parietal, and cingulate neocortices. Structural connectivity using DTI-based tractography complements fcMRI data and confirms anatomical connections between the dentate nucleus, thalamus, and associative cortices. Taken together, these results support the theory that specific neocerebellar subregions are key nodes in parallel, multisynaptic, closed-loop circuits involved in executive, mnemonic, and affective functions.