Comparison of finite element method and finite difference method for solving eletroencephalogram forward problem

Finite element method (FEM) and finite difference method (FDM) were compared for resolution of 3D isotropic eletroencephalogram forward problem, from the point of view of computational accuracy, efficiency and complexity. Three-concentric-sphere model and current dipole were used to simulate the head volume conductor and brain electrical activity, respectively. The effects of dipole eccentricity and grid model size on the solution accuracy and efficiency were addressed. Simulation indicates that the numerical accuracy of FEM is more sensitive to tangential dipoles, while FDM is more sensitive to radial dipoles, and FEM provides similar computational efficiency as FDM for equivalent number of elements. The reconstruction of grid model for FEM is more complex than for FDM, especially to reconstruct the realistic head model.