Influence of white matter inhomogeneous anisotropy on EEG forward computing

In this paper, we model the human head using the Volume and Wang's constraint methods, and study the inhomogeneous anisotropic conductivity for white matter (WM) using finite element method (FEM). To represent the WM accurately, the conductivity ratio approximation (CRA) and statistical conductivity approximation (SCA) techniques are applied to assign inhomogeneous anisotropic conductivity. This model is evaluated and compared with a homogeneous isotropic model and a homogeneous anisotropic model. The results show that the effects of inhomogeneous anisotropic conductivity ofWM on the scalp EEG are significant.