Fig. 2.

Representation of the node and internode regions. A: the three tapering designs of the axons and the myelin around the nodes of Ranvier used in this study. B: the cylindrical capacitor model for the internode. The axon fiber consists of the axon (the inner core) with diameter D_axon, the membrane with thickness Δ_mem, and a layer of myelin of thickness Δ_myelin generating the outer cylinder. The fiber diameter D_fiber is then determined by D_fiber = D_axon + 2 Δ_mem + 2 Δ_myelin ≈ D_axon + 2 Δ_myelin.