Topological reorganization of functional hubs in patients with Parkinson's disease with freezing of gait

Abstract Resting-state functional MRI (rs-fMRI) studies in Parkinson’s disease (PD) patients with freezing of gait (FOG) have implicated dysfunctional connectivity over multiple resting-state networks. While these findings provided information related to the aberrant or altered regional functional connectivity, whether these alterations have any effect on topological reorganization in PD-FOG patients is incompletely understood. In this study, we use rs-fMRI data and graph theoretical approaches to explore the reorganization of resting-state network topology in PD-FOG when compared to those without FOG (PD-nFOG). We found that the PD-FOG patients showed global topological reorganization accompanied by a reduction in efficiency and network strength. There was also a noticeable reorganization of ‘hub’ regions and significantly reduced rich-club connectivity in PD-FOG. Overall our findings demonstrate a widespread topological reorganization in PD-FOG which may further assist in improving our understanding of functional network disturbances associated with PD-FOG.