Modeling noninvasive neurostimulation in epilepsy as stochastic interference in brain networks.
Noninvasive brain stimulation is one of very few potential therapies for medically refractory epilepsy. However, its efficacy remains suboptimal and its therapeutic value has not been consistently assessed. This is in part due to the nonoptimized spatio-temporal application of stimulation protocols for seizure prevention or arrest, and incomplete knowledge of the neurodynamics of seizure evolution. Through simulations, this study investigated electroencephalography (EEG)-guided, stochastic interference with aberrantly coordinated neuronal networks, to prevent seizure onset or interrupt a propagating partial seizure, and prevent it from spreading to large areas of the brain. Brain stimulation was modeled as additive white or band-limited noise, and simulations using real EEGs and data generated from a network of integrate-and-fire neuronal ensembles were used to quantify spatio-temporal noise effects. It was shown that additive stochastic signals (noise) may destructively interfere with network dynamics and decrease or abolish synchronization associated with progressively coupled networks. Furthermore, stimulation parameters, particularly amplitude and spatio-temporal application, may be optimized based on patient-specific neurodynamics estimated directly from noninvasive EEGs.
Department of Radiology and Clinical Research Center, Children’s Hospital Boston and Harvard Medical School, Boston, MA 02115, USA. caterina@mit.edu
Catherine
C
Stamoulis
Bernard S
BS
Chang
D000818:Animals; D001683:Biological Clocks / Q000528:radiation effects*; D001921:Brain / Q000503:physiopathology* / Q000528:radiation effects; D001931:Brain Mapping / Q000379:methods; D003198:Computer Simulation; D004827:Epilepsy / Q000175:diagnosis / Q000503:physiopathology* / Q000517:prevention & control*; D006801:Humans; D008959:Models, Neurological; D015233:Models, Statistical; D009415:Nerve Net / Q000503:physiopathology* / Q000528:radiation effects; D011829:Radiation Dosage; D013269:Stochastic Processes; D050781:Transcranial Magnetic Stimulation / Q000379:methods*