An Improved Solver for the M/EEG Forward Problem

Noninvasive investigation of the brain activity via electroencephalography (EEG) and magnetoencephalography (MEG) involves a typical inverse problem whose solution process requires an accurate and fast forward solver. We propose the Method of Fundamental Solutions (MFS) as a truly meshfree alternative to the Boundary Element Method (BEM) for solving the M/EEG forward problem. The solution of the forward problem is obtained, via the Method of Particular Solutions (MPS), by numerically solving a set of coupled boundary value problems for the 3D Laplace equation. Numerical accuracy and computational load are investigated for spherical geometries and comparisons with a state-of-the-art BEM solver shows that the proposed method is competitive.