At birth, myelin coverage is relatively sparse myelination moves in a wave, first coating the white matter in the cerebral cortex nearest the nape of the neck and gradually moving forward, finally coating the frontal lobes in our mid to late 20s. In the brain, myelin is laid down by cells called oligodendrocytes. In fact, myelinated nerves can carry impulses up to 100 times faster than non-myelinated fibers. In myelinated nerves, rather than an impulse traveling along the length of the cell as it does in gray matter, it can to leap from node to node, increasing the velocity of conduction.Īs the primary messenger service of the brain, myelination allows white matter to pass notes between distant regions at breakneck speed. Myelin coats the surface of all the nerve cells, leaving small gaps – also known as the nodes of Ranvier – every millimeter or so. Share on Pinterest Myelinated axon compared with demyelinated axon.
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