Neuroprosthetic applications of electrical stimulation

Neural prostheses are a developing technology that use electrical activatio n of the nervous system to restore function to individuals with neurologica l impairment. Neural prostheses function by electrical initiation of action potentials in nerve fibers that carry the signal to an endpoint where chem ical neurotransmitters are released, either to affect an end organ or anoth er neuron. Thus, in principle, any end organ under neural control is a cand idate for neural prosthetic control. Applications have included stimulation in both the sensory and motor systems and range in scope from experimental trials with single individuals to commercially available devices. Outcomes of motor system neural prostheses include restoration of hand grasp and re lease in quadriplegia, restoration of standing and stepping in paraplegia, restoration of bladder function (continence, micturition) following spinal cord injury, and electrophrenic respiration in high-level quadriplegia. Neu ral prostheses restore function and pro,ide greater independence to individ uals with disability.