adjective
- lacking a myelin sheath around nerve fibers
Usage: medical; biological
Examples
- Unmyelinated nerve fibers conduct impulses more slowly than myelinated ones.
- Pain signals are often carried by unmyelinated C fibers.
- The autonomic nervous system contains many unmyelinated axons.
- Unmyelinated neurons appear gray in brain tissue.
- Multiple sclerosis damages the myelin sheath, leaving previously myelinated fibers unmyelinated.
- Small diameter unmyelinated fibers are responsible for dull, aching pain.