preganglionic fibers

(redirected from Preganglionic sympathetic)

pre·gan·gli·on·ic fi·bers

a fiber the cell body of which is located in an autonomic nucleus in the spinal cord or brainstem and the axon of which terminates in an autonomic (motor) ganglion; found in nerves conveying sympathetic or parasympathetic fibers.
References in periodicals archive ?
Preganglionic sympathetic fibers originate in the first and second thoracic segments and synapse in the cervical sympathetic ganglia.
Preganglionic sympathetic fibers originate in the first and second thoracic spinal nerves, synapse in the superior cervical ganglion with postganglionic sympathetic fibers, and travel along the external carotid artery and the facial artery to the sweat glands.