Biophysical Model of Cortical Network Activity and the Influence of Electrical Stimulation
Technical Report,15 Aug 2012,14 Aug 2015
Johns Hopkins University Baltimore United States
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We examined the effects of subdural electrical stimulation on a high-density network consisting of several populations of multicompartment cell types. The results can be summarized as follows 1 Electrical stimulation mainly affects and activates axon initial and the most distal axonal segments in neurons. The most distal axonal segments are locations where presynaptic action potentials can originate regardless of the state of the axon initial segment i.e. depolarization, hyperpolarization 2 The effect of dendritic arbor structure on the axonal activation threshold is most prominent in the case of multipolar neurons with large-diameter basalapical dendrites that are oriented parallel to the electric field lines. 3 The timing of presynaptic terminal activation in neurons subjected to electrical stimulation is not solely determined by the axonal delay i.e. orthodromic propagation but rather depends on the details of the applied stimulation field, axonal branching structure and axon orientation in respect to the electrode position. 4 A single stimulation pulse causes a sequence of action potentials ectopically generated in axons, which in turn produce a temporal variation in the timing of postsynaptic neurons activation.