(redirected from nerve stimulator)
Also found in: Dictionary, Thesaurus, Medical, Legal.


see nervous systemnervous system,
network of specialized tissue that controls actions and reactions of the body and its adjustment to the environment. Virtually all members of the animal kingdom have at least a rudimentary nervous system.
..... Click the link for more information.



the cordlike association of nerve tissues that links the brain and nerve ganglia by innervation to the other organs and tissues of the body.

A nerve primarily consists of nerve fibers. In vertebrates many nerves converge to form a bundle that is surrounded by a connective tissue sheath, the perineurium; the thin interstitial layers of connective tissue that separate the individual fibers deep within the bundle constitute the endoneurium. Finally, the entire nerve trunk, comprising several bundles, is covered by an additional sheath, the epineurium.

Nerves can be sensory (also called afferent or centripetal) or motor (also called efferent or centrifugal). Some nerves, for example, those innervating the skeletal muscles, mainly include myelinated, or medullated, fibers; others, for example, the sympathetic nerves, largely consist of unmyelinated, or unmedullated, fibers.

In reptiles, birds, mammals, and man 12 pairs of cranial nerves branch from the brain: the olfactory (cranial nerve I), the optic (cranial nerve II), the oculomotor (cranial nerve III), the trochlear (cranial nerve IV), the trigeminal (cranial nerve V), the abducent (cranial nerve VI), the facial (cranial nerve VII), the acoustic (cranial nerve VIII), the glossopharyngeal (cranial nerve IX), the vagus (cranial nerve X), the accessory (cranial nerve XI), and the hypoglossal (cranial nerve XII). Only the first ten pairs are present in fish and amphibians.

In man there are 31 pairs of spinal nerves: eight cervical, 12 thoracic, five lumbar, five sacral, and one coccygeal. Each pair innervates the effectors and receptors of a certain part of the body. The spinal nerves branch from the spinal cord into two roots—the posterior, or sensory, and the anterior, or motor. Both roots then combine to form a common trunk that consists of both sensory and motor fibers.

Several adjacent nerves can be combined into nerve plexuses, where an exchange of fibers between different nerves can take place. Three large plexuses are distinguished: the cervical, the brachial, and the lumbosacral. Each nerve plexus is the origin of several pairs of nerves; for example, the sacral portion of the lumbosacral plexus gives rise to the sciatic nerves.

Nerves that originate in the ganglia, trunks, and plexuses of the autonomic nervous system constitute a specific group. The optic nerve is remarkable for its large number of fibers; there are more than 1 million in the human optic nerve. Usually, however, there are 103 -104 fibers in a nerve. In invertebrates certain nerves are known to consist of only a few fibers. The peripheral nervous system in animals and man consists of aggregations of nerves.



A bundle of nerve fibers or processes held together by connective tissue.


Any one of the ribs of a groined vault, but esp. a rib which forms one of the sides of a compartment of the groining.


1. any of the cordlike bundles of fibres that conduct sensory or motor impulses between the brain or spinal cord and another part of the body
2. a large vein in a leaf
3. any of the veins of an insect's wing
References in periodicals archive ?
The cost comparison of infraclacicular brachial plexus block by nerve stimulator and ultrasound guidance.
Caption: Implanted vagus nerve stimulators send electricity from a generator in the chest to the nerve in the neck.
Davies and Mcglade also favoured the use of nerve stimulator as a reliable technique for nerve locali- sation in their study of one hundred sciatic nerve blocks: a comparison of localisation techniques.
Most patients who have had a vagus nerve stimulator choose to continue therapy--that is about 71% choose to have their battery replaced rather than turning off or removing the device.
All blocks were performed according to standard procedure using a short beveled 22G, 100mm sheathed needle, with a nerve stimulator guided technique (B Braun, Stimuplex, Germany).
Sometimes the antidepressant drugs work in concert with the stimulator, but it appears to us that when people get better, it is the vagus nerve stimulator that is doing the heavy lifting," Conway explained.
patients who have a vagus nerve stimulator placed experience a significant reduction in seizure frequency and severity, and medication regimens can be significantly decreased.
Currently, the market is limited because only one device is on the market, the vagus nerve stimulator made by Cyberonics Inc.
Approved by the Food and Drug Administration for acute and chronic pain in 2006, the PST is a battery-powered controlled nerve stimulator that weighs about 7 g and is fastened behind the ear by an adhesive backing.
A class-action shareholders' suit has been filed against Houston, TX-based Cyberonics contending that the company misrepresented and failed to disclose information about the FDA's approval of the Vagus Nerve Stimulator CONS) device for the treatment of depression.
You are probably referring to the vagus nerve stimulator (VNS)--a treatment option sometimes called a "pacemaker for the brain.
The purpose of this manuscript is to introduce the vagus nerve stimulator as a new option for patients with uncontrolled seizures thus enhancing their quality of life.