Myelin is an insulating layer, or sheath that forms around nerves, including those in the brain and spinal cord. It is made up of protein and fatty substances. This myelin sheath allows electrical impulses to transmit quickly and efficiently along the nerve cells. If myelin is damaged, these impulses slow down.

Why is myelination important?

Myelin enables nerve cells to transmit information faster and allows for more complex brain processes. The myelination process is vitally important to healthy central nervous system functioning.

Why is it important for neurons to have a myelin sheath?

Myelin can greatly increase the speed of electrical impulses in neurons because it insulates the axon and assembles voltage-gated sodium channel clusters at discrete nodes along its length. Myelin damage causes several neurological diseases, such as multiple sclerosis.