Electromyography and clinical neurophysiology
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Electromyogr Clin Neurophysiol · Jan 1990
Comparative StudyElectrotonic potentials of myelinated nerve fibers.
The extracellular electrotonic potentials of a single myelinated nerve fiber in a volume conductor of infinite extent were studied. The spatial distribution of the transmembrane electrotonic potential was obtained by integrating the system of differential equations constituting the model of the activation of a myelinated nerve fiber. The stimulus was step-like. ⋯ The spatial distribution of the extracellular potentials at various radial distances in the conducting medium was calculated using the line source model. Up to a certain radial distance the discontinuous structure of the myelinated fiber is reflected in the oscillatory nature of the extracellular potentials, while further in the volume conductor the potentials are smooth. The magnitude of the radial decline of the extracellular potentials were compared for myelinated fibers of various internodal distances.