Myelinated vs Unmyelinated
Upper — Myelinated
Myelin sheath (insulator)
Node of Ranvier (ion channels)
Dipole (+/−) jumps between nodes
Lower — Unmyelinated
Dipole propagates continuously
Dipole
Extracellular field (viridis)
The action potential creates a current dipole at the wavefront. In myelinated
fibres this dipole jumps (saltatory conduction) between Nodes of Ranvier.
In unmyelinated fibres it propagates continuously along the membrane.