Numerical Estimation on the Threshold of Nerve Excitation Phenomena by the Application of Current with Multiple Frequencies based on Frankenhaeuser-Huxley Model

Abstract

International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines describes addition equation for electrical stimulation, relevant for frequencies up to 10 MHz, with respect to simultaneous exposure to magnetic fields with multiple frequencies. However, there is no literature which estimated the threshold of electromagnetic field exposure of multiple frequencies. Therefore, the purpose of this article is to estimate the threshold of nerve excitation caused by the application of current with multiple frequencies. In this article, combinations of two kinds of frequencies f 1 and f 2 were investigated for the applying current. The Frankenhaeuser-Huxley model was employed to analyze nerve excitation effects. The ratios of the applied current value to the threshold current value were kept at the same value for each frequency f 1

MorphoSONIC: A morphologically structured intramembrane cavitation model reveals fiber-specific neuromodulation by ultrasound

“…Our myelinated axon model was based on the spatially-extended nonlinear node (SENN) model developed by Reilly et al. (1985) , which underlies a range of low-frequency exposure safety standards (prevention of undesired neurostimulation) and has been extensively used in previous studies on the excitability of myelinated nerve fibers by electrical fields for various applications, including neurostimulation of somatosensory and autonomic nerves ( Gupta et al., 2020 ; Neufeld et al., 2016 ; Samoudi et al., 2017 ), modulation of nerve excitability by multi-frequency and high-frequency currents ( Makino et al., 2020 ; Zhao et al., 2015 ), and minimization of nerve excitation during electroporation procedures ( Mercadal et al., 2017 ). This model represents myelinated axons as a set of nodes with active membrane dynamics based on the Frankenhaeuser-Huxley equations for a Xenopus Ranvier node ( Frankenhaeuser and Huxley, 1964 ) including fast sodium (I Na ), delayed-rectifier potassium (I Kd ), non-specific delayed (I P ) and non-specific leakage (I Leak ) currents, connected by intracellular resistors representing the myelinated internodes ( Figures 1 A and 1B).…”