unmyelinated fiber


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unmyelinated fiber

(ŭn-mī′ə-lĭ-nā′tĭd)
n.
Any of the nerve fibers that lack a fatty myelin sheath but like other nerve fibers are enveloped by a sheath of Schwann cells.

unmyelinated fiber

A nerve fiber that lacks a myelin sheath, although a neurilemma may be present in the peripheral nervous system.
See also: fiber
References in periodicals archive ?
The sinusoidal waveform of the alternating current excites different subpopulations of nerve fibers as a function of frequency: 2,000 Hz, large myelinated fibers; 250 Hz, small myelinated fibers; and 5 Hz, small unmyelinated fibers.
In multiple sclerosis, "DT-MRI is the only technique that highlights some unmyelinated fibers, where conventional techniques don't allow you to see them," Dr.
The mice exhibited a significant reduction in tremors and neural symptoms posttransplant, and the investigators detected remyelination of previously unmyelinated fibers.