OpenMEEG for M/EEG forward modeling: a comparison study

Neuroimaging with magneto and electroencephalography (M/EEG) requires to compute the forward problem. It consists in predicting what is measured by MEG or EEG sensors due to a configuration of current generators within the head. When considering realistic head models, the equations derived from Maxwell equations can only be solved numerically. The Boundary Element Method is a standard approach to address this problem. However, different mathematical and computational variants exist within this class of BEM solvers. At least two BEM formulations exist for M/EEG forward modeling (Geselowitz, 1967 and Kybic et al., 2005). Also implementation details vary between the different software packages (e.g. the precision of the numerical integrations). In order to investigate the influence of such differences, we have conducted a numerical experiment that evaluates the precision of 4 different freely available BEM solvers. Results show that OpenMEEG outperforms the alternative software packages.