Why is a myelinated axon so much faster? The signal does not crawl along every inch. It leaps from node to node and skips the insulated stretches. Watch two signals race.
Two axons, one signal each
Conduction speedmyelin makes it leap
Two ways to send a signalLook at the unmyelinated axon on top. The signal must rebuild itself at every point, so it is slow. Now look at the myelinated axon below. The signal only rebuilds at the bare nodes of Ranvier. It jumps over the stretches covered in myelin. This is saltatory conduction. It is faster, and it uses less energy.
📷 Reference image
A real labeled figure to compare with the interactive above.
Saltatory Conduction — OpenStax, CC BY 4.0 (via Wikimedia Commons)
