Altered dynamic functional connectivity of motor cerebellar with sensorimotor network and default mode network in Juvenile Myoclonic Epilepsy

Abstract

Abstract Background To investigate the role of dynamic functional connectivity (dFC) of motor cerebellar motor cerebellar-cortical circuitry in juvenile myoclonic epilepsy (JME). Methods The motor cerebellum is divided into five lobules (I–V, VI, VIIb, VIIIa, and VIIIb). We adopted the resting-state EEG-fMRI and the sliding-window approach to explore the dFC of motor cerebellum with SMN and DMN between30 JME patients compared with thirty sex-and age-matched health controls (HCs). Moreover, the relationship between the dFC variability and clinical variables (disease duration, age at disease onset, and frequency score of myoclonic seizures) were also investigated in JME group. Results Compared to HCs, the JME group presented increased dFC between the motor cerebellum with sensorimotor network(SMN)and default mode network (DMN). Specifically, connectivity between lobule Ⅶb and right precentral gyrus and left inferior parietal lobule (IPL); between lobule Ⅷa and right middle frontal gyrus (MFG) and left IPL; and between lobule Ⅷb and left MFG, bilateral superior parietal gyrus (SPG), and left precuneus. In addition, within the JME group, the strength of dFC between lobule Ⅷb and left precuneus was negatively (r=-0.424, p = 0.025, Bonferroni correction) related with the frequency score of myoclonic seizures. Conclusion JME presents altered dFC variability in motor cerebellum with SMN and DMN, and the strength of dFC between lobule Ⅷb and left precuneus is associated with the severity of JME. These results may provide novel information about the dynamic and wide involvement of the motor cerebellum in the pathophysiology of JME, specifically, the motor cerebellum is involved in motor symptoms.