Most of the materials have nearly constant electromagnetic characteristics at low frequencies. Nonetheless, biological tissues are not the same; they are highly dispersive, even at low frequencies. Cable theory is the most famous method for analyzing nerves though a common mistake when studying the model is to consider a constant parameter versus frequency. This issue is discussed in the present article, and the analysis of how to model the dispersion in the cable model is proposed and explained. The proposed dispersive model can predict the behavior of excitable cells versus stimulations with single frequency or wide band signals. In this article, the nondestructive external stimulation by a coil is modeled and computed by finite difference method to survey the dispersion impact. Also, 5% to 80% difference is shown between the results of dispersive and nondispersive models in the 5 Hz to 4 kHz investigation. The disagreement expresses the dispersion notability. The proposed dispersive method assists in accurate device design and signal form optimization. Noise analysis is also achieved by this model, unlike the conventional models, which is essential in the analysis of single neurons or central nervous system, EEG and MEG records.
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