The periaxonal space in myelinated axons is conductive (~50 ohm cm). Together with a rapidly charging myelin sheath and relatively sealed paranodes, periaxonal conduction shapes the saltating voltage profiles of transaxonal (Vm), transmyelin (Vmy) and transfibre (Vmym) potentials. This model exemplifies double cable saltatory conduction across both time and space, and is the same cell (#6) as seen in Movie S4 of Cohen et al. 2020. This model version allows one to visualize and manipulate the controlling parameters of a propagating action potential. Further notes: The corresponding potentials in NEURON to those named above are v, vext (or vext[0]) and v+vext, respectively. The loaded biophysical parameters were those optimized for this cell (Cohen et al. 2020).
Model Type: Axon; Channel/Receptor; Dendrite; Extracellular; Glia; Neuron or other electrically excitable cell
Cell Type(s): Neocortex L5/6 pyramidal GLU cell; Myelinated neuron
Currents: Ca pump; I Calcium; I h; I K,Ca; I K,leak; I L high threshold; I T low threshold; I M; I Na,p; I Na,t; I Sodium; I Potassium
Model Concept(s): Action Potentials; Active Dendrites; Axonal Action Potentials; Conductance distributions; Conductances estimation; Detailed Neuronal Models; Electrotonus; Extracellular Fields; Membrane Properties; Multiple sclerosis; Parameter sensitivity; Double cable
Simulation Environment: NEURON
Implementer(s): Cohen, Charles CH [c.cohen at gmx.com]; Kole, Maarten [m.kole at nin.knaw.nl]
References:
Cohen CCH et al. (2020). Saltatory Conduction along Myelinated Axons Involves a Periaxonal Nanocircuit Cell.