myelin sheath

American  

noun

Anatomy.

1. a wrapping of myelin around certain nerve axons, serving as an electrical insulator that speeds nerve impulses to muscles and other effectors.

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Etymology

Origin of myelin sheath

First recorded in 1895–1900

Example Sentences

Demyelination is the process in which the myelin sheath -- a protective, insulating layer surrounding nerve fibers in the brain and spinal cord -- is damaged or destroyed.

From Science Daily

Oligodendrocytes, the cells that produce myelin to insulate nerve fibers, expressed fewer genes required for maintaining and regenerating the myelin sheath.

From Science Daily

The research showed that MS first targets the myelin sheath.

From Science Daily

In MS, the immune system mistakenly attacks the myelin sheath, a protective layer that insulates nerve fibers.

From Science Daily

However, EBV infection has been linked to several diseases, including MS: an incurable, chronic autoimmune disease that causes the body's immune system to attack the myelin sheath of neurons in the brain and nervous system.

From Science Daily