Solving the EEG Forward Problem by FDM and FEM

In this paper, the finite element method (FEM) and the finite difference method (FDM) were compared for the resolution of the 3D isotropic EEG forward problem, from the point of view of computational complexity and accuracy. The effects of dipole eccentricity and grid model size on solution accuracy and efficiency are addressed in the simulations. The present simulation study indicates that the numerical accuracy of FEM is more sensitive to tangential dipoles, while FDM is more sensitive to radial dipoles, and the FEM provides similar computational efficiency as FDM for equivalent number of elements. But the reconstruction of grid model for FEM is more complex than for FDM, especially to reconstruct the realistic head model.