Dyadic Green’s Function Studies for the Three-shell Head Model

In this work, we employ analytical expressions for the calculation of the dyadic Green’s function (DGF) of the isotropic three-shell head model, due to an infinitesimal electric dipole located in the internal core that corresponds to the brain. We compute the electric field obtained from this DGF and compare and validate our analytical results with HFSS commercial software when the dipole is inside a single sphere. Then, we numerically examine the behavior of the electric field due to the placement of the dipole inside a three-shell spherical head model. Finally, we discuss how the isotropic model can be extended to the more complicated anisotropic one by considering a volume integral equation approach.