Resting-State Network Analysis Reveals Altered Functional Brain Connectivity in Essential Tremor.

ABSTRACT

INTRODUCTION: Essential tremor (ET) comprises motor and non-motor related features, while the current neuro-pathogenetic basis is still insufficient to explain the etiologies of ET. While cerebellum associated circuits have been discovered, the large-scale cerebral network connectivity in ET remains unclear. This study aimed to characterize the ET in terms of functional connectivity as well as network. We hypothesized that the resting-state network within cerebrum could be altered in ET patients. METHODS: Resting-state functional MRI (fMRI) was used to evaluate the inter- and intra-network connectivity as well as the functional activity in ET and normal control. Correlation analysis was performed to explore the relationship between resting-state network metrics and tremor features. RESULTS: Comparison of inter-network connectivity indicated a decreased connectivity between default mode network and ventral attention network in ET group (P<0.05). Differences in functional activity (assessed by amplitude of low frequency fluctuation, ALFF) were found in several brain regions participating in various resting-state networks (P<0.05). ET group generally have higher degree centrality over normal control. Correlation analysis has revealed that tremor features are associated with inter-network connectivity (|r|=0.135-0.506), ALFF (|r|=0.313-0.766), and degree centrality (|r|=0.523-0.710). CONCLUSION: Alterations in the cerebral network of ET was detected by using resting-state fMRI, demonstrating a potentially useful approach to explore the cerebral alterations in ET.