Finite element modeling of current dipoles using direct and subtraction methods for EEG forward problem

Purpose - The resolution of electroencephalography (EEG) forward problem by the finite element method (FEM) involves the modeling of current dipoles with the singularities. The purpose of the paper is to investigate the accuracy issue of the two alternative methods, the direct method and the subtraction method for the modeling of current dipoles. Design/methodology/approach - Finite element modeling of current dipoles using the direct method and the alternative implementations of the subtraction method. Findings - The accuracy and the performance of different methods are compared through a four-layer spherical head model with available analytical solution. Results show that the subtraction method involving only the surface integrals provides the best accuracy. Originality/value - The subtraction method removes the difficulty of modeling the singularity of current dipoles but the accuracy depends on the implementation.