Myelin is a concentrically laminated membrane structure surrounding an axon around which lamellae (or cellular protrusions) repeat radially at a period of about 12 nm (Waxman, Kocsis & Stys 1995 ...

The speed of the action potential isn't constant, they assert, but modulated by changes in the size of the nano-pearls, which in turn are caused by mechanical changes in the axon's membrane and ...