Electrical neurostimulation for chronic pain: on selective relay of sensory neural activities in myelinated nerve fibers

摘要

Chronic pain affects about 100 million adults in the US. Despite their greatneed, neuropharmacology and neurostimulation therapies for chronic pain havebeen associated with suboptimal efficacy and limited long-term success, astheir mechanisms of action are unclear. Yet current computational models ofpain transmission suffer from several limitations. In particular, dorsal columnmodels do not include the fundamental underlying sensory activity traveling inthese nerve fibers. We developed a (simple) simulation test bed of electricalneurostimulation of myelinated nerve fibers with underlying sensory activity.This paper reports our findings so far. Interactions between stimulation-evokedand underlying activities are mainly due to collisions of action potentials andlosses of excitability due to the refractory period following an actionpotential. In addition, intuitively, the reliability of sensory activitydecreases as the stimulation frequency increases. This first step opens thedoor to a better understanding of pain transmission and its modulation byneurostimulation therapies.