Electromagnetic Modeling of Brain Waves based on Full-wave Analysis

Document Type : Original Article

Authors

1 Faculty of Electrical and Computer Engineering, Babol Institute of Technology, Babol, Iran

2 Faculty of Physics, Babol Institute of Technology, Babol, Iran,

Abstract

In this paper by electromagnetic modeling of neurons in brain, the brain waves have been derived in a full-wave way. Now, in all clinics and research centers, traditionally, it has been done by using the quasi-static approximation of the Maxwell equation in electromagnetic. However, the error rate resulting from the approximation has not been studied upon the final results. This issue becomes more noticeable due to increasing the sensitivity of today's modern sensors. In this paper, first, with an overview of the basics of applying quasi-static approximation in the analysis brain waves, ambiguities about the suitability of this approximation are presented and the necessity of full-wave solution of the problem is expressed. Then, in the simplest form, the electromagnetic fields aroused from a current dipole where is located in the center of a sphere with known conductivity is written in terms of Bessel and Hankel function expansion; and the problem has been solved in a full-wave way by using of scattering theories in electromagnetic. Finally, the curve of relative difference measure (RDM) between quasi-static and full-wave solution has been drawn in terms of frequency conductivity. One of the important achievements of full-wave modeling is enriching the information resulted from EEG and MEG and consequently extracting more accurate patterns from brain activities.

Keywords


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