Altered Structural and Functional Connectivity of Juvenile Myoclonic Epilepsy: An fMRI Study

Abstract

The aim of this study was to investigate the structural and functional connectivity (FC) of juvenile myoclonic epilepsy (JME) using resting state functional magnetic resonance imaging (rs-fMRI). High-resolution T1-weighted magnetic resonance imaging (MRI) and rs-fMRI data were collected in 25 patients with JME and in 24 control subjects. A FC analysis was subsequently performed, with seeding at the regions that demonstrated between-group differences in gray matter volume (GMV). Then, the observed structural and FCs were associated with the clinical manifestations. The decreased GMV regions were found in the bilateral anterior cerebellum, the right orbital superior frontal gyrus, the left middle temporal gyrus, the left putamen, the right hippocampus, the bilateral caudate, and the right thalamus. The changed FCs were mainly observed in the motor-related areas and the cognitive-related areas. The significant findings of this study revealed an important role for the cerebellum in motor control and cognitive regulation in JME patients, which also have an effect on the activity of the occipital lobe. In addition, the changed FCs were related to the clinical features of JME patients. The current observations may contribute to the understanding of the pathogenesis of JME.

Reconfiguration of dynamic large‐scale brain network functional connectivity in generalized tonic–clonic seizures

“…But no significant result was found in network level. This result was similar with the previous studies (T. Yang et al, ; Zhong et al, ), and might suggest that the static FC reflects one side of specific alteration in patients with GTCS. Meanwhile, the findings strengthened the necessity of FC temporal variability in company with static FC analysis to explore the dysfunction in IGE.…”

“…Our previous resting state FC study (Jia et al, ) and a study by Song et al () found significantly decreased FC within the default mode network (DMN) in GTCS compared with that in healthy controls (HC), suggesting that abnormal connectivity in DMN might be associated with the impaired consciousness in GTCS. In addition, disrupted interconnections in the DMN, dorsal attention network (DAN), sensorimotor network (SMN), visual network (VN) and auditory network (AN) were observed in IGE, suggesting neural correlates of deficits of self‐process and cognitive function in patients (Li et al, ; Li et al, ; Wang et al, ; Zhong et al, ). Up to now, many fMRI studies have provided evidence to support the stationary alteration of FC in patients with GTCS during fMRI scanning.…”

Dysfunctional white‐matter networks in medicated and unmedicated benign epilepsy with centrotemporal spikes

“…To date, DTI has been widely used to characterize the structural architecture of the white matter; however, it is unsuitable for the detection of the neural activity and brain functions inside the white matter. Functional magnetic resonance imaging (fMRI) based on blood oxygen level‐dependent (BOLD) signals is an effective technique to uncover the neural activity and relevant functions of the gray matter in neuropsychology and clinical neurological diseases (Chen, Liu, et al, ; Dong et al, ; Duan et al, ; Jia et al, ; Zhong et al, ). Recently, greater attention focused on the detection of neural activation and functional organization in the white matter by using the fMRI (Ding et al, ; Fabri & Polonara, ; Fabri, Polonara, Mascioli, Salvolini, & Manzoni, ; Gawryluk, Mazerolle, Brewer, Beyea, & D'Arcy, ; Gawryluk, Mazerolle, & D'Arcy, ; Jiang, Luo, Li, Li, et al, ; Marussich, Lu, Wen, & Liu, ; Peer, Nitzan, Bick, Levin, & Arzyt, ).…”

Altered dynamic effective connectivity of the default mode network in newly diagnosed drug-naïve juvenile myoclonic epilepsy

“…With advances in functional magnetic resonance imaging (fMRI) techniques, researchers have made significant progress in understanding the pathogenesis of JME ( Baykan and Wolf, 2017 , Wolf et al, 2015 ). There has been ample evidence of disrupted brain networks, including thalamo-cortical, fronto-insula, default modal, basal ganglia, sensorimotor networks, etc., in JME patients ( Dong et al, 2016 , Gleichgerrcht et al, 2015 , Lee and Park, 2019 , O'Muircheartaigh et al, 2012 , Paulus et al, 2015 , Wang et al, 2019 , Zhong et al, 2018 ). However, studying the dysfunctions of brain networks in patients who have been treated with AEDs makes it difficult to differentiate brain changes caused by the disease itself from a potential prominent changes caused by AEDs.…”

“…Functional disruption of the DMN have been recently revealed in patients with JME. For example, patients with JME showed decreased functional interactions between the PCC and MPFC ( McGill et al, 2012 ); the coupling of spontaneous fluctuation and functional connectivity (FC) in posterior regions of the DMN was altered in patients and associated with clinical symptoms during seizures ( Jia et al, 2018 ); aberrant FC in hippocampus was also involved in the cognitive dysregulation of JME ( Zhong et al, 2018 ). Taken together, these findings suggested that the DMN is prominently affected in patients with JME ( Parsons et al, 2020 ), and a specific investigation targeting DMN may lead new insights to revealing the pathogenesis of JME at the early phase of this disorder.…”