title: How does vagal nerve stimulation (VNS) change EEG brain functional connectivity?
abstract: An effect of vagal nerve stimulation (VNS) on cortical synchronization has been postulated but remains to be verified. In this study we investigated the impact of VNS on functional connectivity (Fc) using direct intracerebral recordings (stereotactic EEG, SEEG). Five patients with epilepsy who underwent SEEG recordings during ongoing VNS therapy were investigated. Interdependencies between twenty-six selected bipolar SEEG channels were estimated by nonlinear regression analysis during ON and OF periods of stimulation. In comparison with OFF periods, the ON periods disclosed higher values for four patients (P1, P3, P4, P5) and lower values for one patient (P2). From thresholded graphs, we observed increased connections between several brain regions in P1 and P5 and decreased connections in P2. Finally, the only decreased Fc occurring during VNS corresponded to the responder patient, suggesting that therapeutic impact might be related to this mechanism.
authors: Aix Marseille Université, Institut de Neurosciences des Systèmes, Marseille, F-13005, France; AP-HM, Hôpital de la Timone, Service de Neurophysiologie Clinique, Marseille, F-13005, France. Electronic address: fabrice.bartolomei@ap-hm.fr.
authors: Fabrice
authors: F
authors: Bartolomei
authors: Aix Marseille Université, Institut de Neurosciences des Systèmes, Marseille, F-13005, France; AP-HM, Hôpital de la Timone, Service de Neurophysiologie Clinique, Marseille, F-13005, France.
authors: Francesca
authors: F
authors: Bonini
authors: Aix Marseille Université, Institut de Neurosciences des Systèmes, Marseille, F-13005, France.
authors: Elsa
authors: E
authors: Vidal
authors: Aix Marseille Université, Institut de Neurosciences des Systèmes, Marseille, F-13005, France; AP-HM, Hôpital de la Timone, Service de Neurophysiologie Clinique, Marseille, F-13005, France.
authors: Agnes
authors: A
authors: Trébuchon
authors: Aix Marseille Université, Institut de Neurosciences des Systèmes, Marseille, F-13005, France; AP-HM, Hôpital de la Timone, Service de Neurophysiologie Clinique, Marseille, F-13005, France.
authors: Stanislas
authors: S
authors: Lagarde
authors: Aix Marseille Université, Institut de Neurosciences des Systèmes, Marseille, F-13005, France.
authors: Isabelle
authors: I
authors: Lambert
authors: Aix Marseille Université, Institut de Neurosciences des Systèmes, Marseille, F-13005, France; AP-HM, Hôpital de la Timone, Service de Neurophysiologie Clinique, Marseille, F-13005, France.
authors: Aileen
authors: A
authors: McGonigal
authors: AP-HM, Hôpital de la Timone, Service de Neurochirurgie Pédiatrique, Marseille, F-13005, France.
authors: Didier
authors: D
authors: Scavarda
authors: AP-HM, Hôpital de la Timone, Service de Neurochirurgie Fonctionnelle, Marseille, F-13005, France.
authors: Romain
authors: R
authors: Carron
authors: Aix Marseille Université, Institut de Neurosciences des Systèmes, Marseille, F-13005, France.
authors: Christian G
authors: CG
authors: Benar
mesh_terms: D000328:Adult; D001921:Brain / Q000503:physiopathology*; D002648:Child; D003344:Cortical Synchronization / Q000502:physiology; D000069279:Drug Resistant Epilepsy / Q000503:physiopathology / Q000601:surgery; D000069280:Electrocorticography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009434:Neural Pathways / Q000502:physiology; D017711:Nonlinear Dynamics; D012044:Regression Analysis; D012815:Signal Processing, Computer-Assisted; D055536:Vagus Nerve Stimulation; D055815:Young Adult
keywords: EEG; Focal epilepsy; Functional connectivity; Stimulation; Synchrony; Vagus nerve