Effects of anti-seizure medications on resting-state functional networks in juvenile myoclonic epilepsy: An EEG microstate analysis

Objective

Juvenile myoclonic epilepsy (JME) is associated with large-scale brain network dysfunction. This study aims to investigate how anti-seizure medication (ASM) treatment alters resting-state functional networks in JME patients through resting-state EEG microstate analysis.

Methods

Ninety-six subjects participated in this study: 24 healthy controls (HC), 29 newly diagnosed JME patients who had not started ASMs therapy (JME-NM), and 43 JME patients on ASMs treatment with effective seizure control (JME-M). EEG data were collected for 10 min while participants were awake and resting with their eyes closed, using a standard 19-channel recording system. EEG topographies were categorized into four microstate classes (A, B, C, D), and parameters such as mean duration, occurrence rate, time coverage, and transition probabilities between microstates were computed and compared among the three groups. Advanced statistical methods were employed to ensure the robustness and validity of the findings.

Results

Significant alterations in EEG microstate characteristics were observed in untreated JME patients (JME-NM) compared to both healthy controls and treated patients. Microstate B had a markedly reduced mean duration in the JME-NM group, while microstate A displayed an increased occurrence rate and greater time coverage. Transition probabilities between specific microstates, such as from A to C, A to D, and B to C, were also significantly different in the JME-NM group. The normalization of these parameters in the JME-M group suggests that ASMs effectively stabilize altered brain networks, potentially mitigating the pathophysiological disruptions associated with JME.

Conclusion

This study demonstrates that ASMs effectively normalize disruptions in sensory-motor and visual networks in JME patients. EEG microstate analysis provides a dynamic view of brain network alterations and offers potential as a biomarker for the diagnosis and monitoring of JME, as well as for evaluating treatment response. These findings advance our understanding of the neurophysiological mechanisms underlying JME.