Neuroprosthetic Applications of Electrical Stimulation

Abstract

Neural prostheses are a developing technology that use electrical activation of the nervous system to restore function to individuals with neurological impairment. Neural prostheses function by electrical initiation of action potentials in nerve fibers that carry the signal to an endpoint where chemical neurotransmitters are released, either to affect an end organ or another neuron. Thus, in principle, any end organ under neural control is a candidate 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 release 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. Neural prostheses restore function and provide greater independence to individuals with disability.

Decision for reconstructive interventions of the upper limb in individuals with tetraplegia: the effect of treatment characteristics

“…12,13 In the development, application and evaluation of new techniques, the opinion of the public and/ or patients is increasingly considered to be very important. This is emphasized by the fact that studies show differences in clinician and consumer preferences with respect to health outcome and non-health outcome factors of therapeutic interventions.…”

Development of an extraocular retinal prosthesis: Evaluation of stimulation parameters in the cat

“…Because of the greater distance between extraocular electrodes and the target neurons in the retina compared with intraocular implants, larger electrodes and higher stimulus currents will be necessary in such a prosthesis. 23,24 Therefore, extraocular stimulation will lead to the development of a lower resolution visual prosthesis than may be possible with smaller intraocularly placed electrodes. However, it is hoped that if a prosthesis can be developed with enough electrodes to produce distinct phosphene sensations, then such a device may be able to function as a useful electronic travel aid for the rehabilitation of blind patients.…”

Surface stimulation of the brain with a prototype array for a visual cortex prosthesis

“…1 Successful applications of neuroprosthetic technology are well known in clinical medicine and include the use of cochlear implants for deafness, 2 cardiac pacemakers for arrhythmias, 3 and the use of muscular stimulation in paralysis. 4 These three common indications for electrical stimulation in modern medical practice illustrate the ability of neural prostheses to restore useful function in disorders of sensory, autonomic, and motor systems. 5 The next frontier in neural prosthesis research is to develop a medical device to restore visual perceptions to irreversibly blind patients, which is functionally useful, and clinically acceptable.…”