The Cerebellar Functional Connectivity In Patients With Generalized Tonic-clonic Seizures

Generalized tonic-clonic seizures(GTCS)is one of the most common epilepsy in idiopathic generalized epilepsy(IGE)which performs generalized muscular stiffness,uncontrollable muscle contraction and loss of consciousness with generalized spike and wave discharges(GSWD)among 2.5 to 5Hz.Due to the patients with GTCS may break out anytime and anywhere with uncontrollable,they always live and work in dangerous.The mortality rate of patients is also higher than the normal which makes patients under an unhealthy state in physicality and mentality.The neurophysiological mechanisms of GTCS are unclear still now,but with the development of technology,researchers use variety methods and angles to explore the principles of GTCS.The methods conclude electroencephalogram(EEG),magnetoencephalogram(MEG),functional magnetic resonance imaging(fMRI),diffusion tensor imaging(DTI),magnetic resonance spectroscopy(MRS)and angles conclude gray matter,white matter or specific areas.Recently,cerebellar plays an important role in GTCS.To research the brain function,especially the cerebellar function in patients with GTCS at multiple angles,we have studied them mainly from three aspects.In this study,we selected 18 GTCS patients and 20 normal controls as the control group,used their resting-state and task fMRI data to study.First,we studied the difference in brain regions of patients under the activation of a hand motor task.Compared patients and controls,we found that the crus2 was in active increasedly in patients.It may be a compensatory effect on motor function impairment in patients.The postcentral gyrus was in deactive during the task in patients.It may be the patients’ uncontrolled clonic attacks had affected their primary sensory perception which made them less capable of sensory ability.Then we started from the network level to study the connectivity.We selected 14 network components from the resting-state and the task fMRI with independent component analysis(ICA)to measure the functional connectivity and the functional network connectivity.We found the functional connectivity of the sensorimotor network such as the cerebellum network had abnormalities in both the resting state and the task.The functional connectivity between cerebellum network and other networks also had abnormalities during the task.It suggested us that cerebellum may have decreased efficiency of exercise information processing and appeared the inhibition of cerebellar in patients.Meanwhile we found there were abnormalities in the cognitive network among patients which may relate to patients’ loss of awareness.The general decline functional connectivity of intra-networks under the task among patients may also be related to the impairment of the ability when patients do a task.In the last part of this research we studied the differences between the network and their mapped sub-regions of cerebellum from the voxel level.We used mask to extract the cerebellum,calculated the functional connectivity of each voxel in the cerebellum to all the voxels across the whole brain,analyzed 12 network components by ICA,regressed with a regression model and reconstructed to cerebellum in the end.Compared with the normal controls,we found the values of FPN and BGN mapped cerebellar sub-regions were negative among patients which indicated that the patients had a missing or reduced map in this area.These results may be related to the loss of awareness,abnormal discharge or clonic attacks.In this study,we researched the patients from resting-state to task,from activation of task and network level to voxel level.The result shown that there were differences in cerebellum of patients no matter in the activation of task,network level or voxel level corresponded to the network function partition.We hoped that the study can provide more information to help us learn the physiological and pathological mechanism about GTCS from wide horizons.