Cortico-muscular and cortico-cortical coherence changes resulting from Perampanel treatment in patients with cortical myoclonus. Issue 5 (May 2021)

• Record Type: Journal Article
• Authors: Franceschetti, S.; Visani, E.; Rossi Sebastiano, D.; Duran, D.; Granata, T.; Solazzi, R.; Varotto, G.; Canafoglia, L.; Panzica, F.
• Is Part Of: Clinical neurophysiology. Volume 132:Issue 5(2021)
• Page Start: 1057
• Page End: 1063
• Publication Date: 2021-05
• Subjects: Myoclonus -- MEG -- cortico-muscular coherence (CMC) -- Cortico-cortical connectivity -- Perampanel -- Progressive myoclonus epilepsy (PME); Neurophysiology -- Periodicals; Electroencephalography -- Periodicals; Electromyography -- Periodicals; Neurology -- Periodicals; 612.8
• DOI: 10.1016/j.clinph.2021.01.018
• Languages: English
• ISSNs: 1388-2457

Abstract

Highlights: In patients with progressive myoclonus epilepsy, cortico-muscular coherence significantly decreased during Perampanel treatment. Out-degree and betweenness centrality increased on contralateral motor cortex during Perampanel treatment. The improvement of the myoclonus induced by Perampanel resulted from restored leadership of the contralateral motor cortex. Abstract: Objective: To investigate the mechanisms by which Perampanel (PER) reduces the severity of action myoclonus, we studied on MEG signals the changes occurring in cortico-muscular coherence (CMC) and cortico-cortical connectivity in patients with progressive myoclonus epilepsies. Methods: The subjects performed an isometric extension of the hand; CMC and cortico-cortical connectivity were assessed using autoregressive models and generalized partial-directed coherence. The contralateral (Co) sensors showing average CMC values >0.7 of the maximum (set to 1) were grouped as central (C) regions of interest (ROI), while adjacent sensors showing CMC values >0.3 were grouped as Surrounding (Sr) ROIs. Results: Under PER treatment, CMC decreased on Co C and Sr ROIs, but also on homologous ipsilateral (Ip) ROIs; out-degrees and betweenness centrality increased in Co ROIs and decreased in Ip ROIs. The flow from Ip to Co ROIs and from activated muscles to Ip C ROI decreased. Conclusion: The improvement of myoclonus corresponded to decreased CMC and recovered leadership of the cortical regions directly involved in the motor task, with a reduced interference of ipsilateral areas. Significance: Our study highlights on mechanisms suitable to treating myoclonus and suggests the role of a reduced local synchronization together a better control of distant synaptic effects.