Complex discharge‐affecting networks in juvenile myoclonic epilepsy: A simultaneous EEG‐fMRI study

Abstract

Juvenile myoclonic epilepsy (JME) is a common subtype of idiopathic generalized epilepsies (IGEs) and is characterized by myoclonic jerks, tonic-clonic seizures and infrequent absence seizures. The network notion has been proposed to better characterize epilepsy. However, many issues remain not fully understood in JME, such as the associations between discharge-affecting networks and the relationships among resting-state networks. In this project, eigenspace maximal information canonical correlation analysis (emiCCA) and functional network connectivity (FNC) analysis were applied to simultaneous EEG-fMRI data from JME patients. The main findings of our study are as follows: discharge-affecting networks comprising the default model (DMN), self-reference (SRN), basal ganglia (BGN) and frontal networks have linear and nonlinear relationships with epileptic discharge information in JME patients; the DMN, SRN and BGN have dense/specific associations with discharge-affecting networks as well as resting-state networks; and compared with controls, significantly increased FNCs between the salience network (SN) and resting-state networks are found in JME patients. These findings suggest that the BGN, DMN and SRN may play intermediary roles in the modulation and propagation of epileptic discharges. These roles further tend to disturb the switching function of the SN in JME patients. We also postulate that emiCCA and FNC analysis may provide a potential analysis platform to provide insights into our understanding of the pathophysiological mechanism of epilepsy subtypes such as JME. Hum Brain Mapp 37:3515-3529, 2016. © 2016 Wiley Periodicals, Inc.

Unravelling the brain networks driving spike‐wave discharges in genetic generalized epilepsy—common patterns and individual differences

“…We observed activity increases in the SN in 58% of patients. Network studies in GGE patients corroborate this finding in demonstrating altered connectivity within the SN and between this and other RSNs, such as DMN and DAN . This might indicate altered processing of salient information in GGE patients and might be associated with attentional dysfunction during absence seizures.…”

MATLAB Toolboxes for Reference Electrode Standardization Technique (REST) of Scalp EEG

“…So far, superior performance of REST reference has been proved in various studies such as ERPs (Tian and Yao, 2013 ; Liu et al, 2015 ; Yang et al, 2017 ) and EEG network analyses (Qin et al, 2010 ; Chella et al, 2016 ; Lei and Liao, 2017 ). The REST is likely to represent a promising EEG standardization technique for various areas of research, such as epilepsy (Li et al, 2009 ; Kugiumtzis and Kimiskidis, 2015 ; Dong et al, 2016 ; Kimiskidis et al, 2017 ), depressive disorder (Khodayari-Rostamabad et al, 2013 ) and BCIs (He et al, 2013 ; Yin et al, 2016 ) etc. In addition, it has been argued that the performance of REST reference may be influenced by the electrode density and head model; however, several studies have showed that REST can reduce the potential bias introduced by other references for many of EEG channels ranging from 16 to 128 and for different accuracy levels of the head model (Zhai and Yao, 2004 ; Liu et al, 2015 ; Chella et al, 2016 ).…”

Disrupted Coupling Between the Spontaneous Fluctuation and Functional Connectivity in Idiopathic Generalized Epilepsy

“…Thus, the altered coupling in motor-related intrinsic networks might imply multi-levels abnormality related to motor function in IGE. In addition, the cerebellum may be associated with the regulation of epileptic discharges in IGE ( 8 ). In previous EEG-fMRI studies, patients with IGE showed significant activation related to GSWDs in the cerebellum ( 6 , 34 ).…”