Physiological Stimulators: From Electric Fish to Programmable Implants

The application of electricity to the human body for medical purposes probably predates written history. Less venerable, but far more practical, is the delivery of electricity to internal cellular structures from signal generators placed within the body. The human cardiovascular system and the central nervous system were the filrst to benefit from commercially available implantable stimulators. The list of target structures, however, is expanding rapidly; and the number of medical indications for this kind of treatment is growing even faster. We are moving swiftly into an era in which the site-specific applications of well-defined electrical stimuli under very sophisticated noninvasive control will be the treatment of choice for a great many disorders, both physical and mental.