Neocortical Simulation for Epilepsy Surgery Guidance: Localization and Intervention
New surgical and localization techniques allow for precise and personalized evaluation and treatment of intractable epilepsies. These techniques include the use of subdural and depth electrodes for localization, and the potential use for cell-targeted stimulation using optogenetics as part of treatment. Computer modeling of seizures, also individualized to the patient, will be important in order to make full use of the potential of these new techniques. This is because epilepsy is a complex dynamical disease involving multiple scales across both time and space. These complex dynamics make prediction extremely difficult. Cause and effect are not cleanly separable, as multiple embedded causal loops allow for many scales of unintended consequence. We demonstrate here a small model of sensory neocortex which can be used to look at the effects of microablations or microstimulation. We show that ablations in this network can either prevent spread or prevent occurrence of the seizure. In this example, focal electrical stimulation was not able to terminate a seizure but selective stimulation of inhibitory cells, a future possibility through use of optogenetics, was efficacious.
KeywordsEpilepsy Neurosurgery Medial temporal lobe Computer simulation Neurodynamics Seizures Neocortex Pyramidal cells Optogenetics Electroencephalography Personalized medicine Microstimulation
Research supported by NIH R01MH086638 and DARPA N66001-10-C-2008.
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