A high-resolution anisotropic finite-volume head model for EEG source analysis.

摘要

Source analysis of the electroencephalogram (EEG) provides a noninvasive method of localizing electrical/functional activity of the brain and is particularly important in the diagnosis of certain neurological disorders such as epilepsy. This research focuses on improving the accuracy of EEG source analysis by developing a high-resolution finite-volume head model that accounts for anisotropic conductivities of the human head. The numerical accuracy of the finite volume method (FVM) formulation is evaluated, with the analytical solution for a spherical head serving as the "gold standard" of comparison. The FVM formulation is shown to produce accurate results, but severe anisotropy appears to be a problem at the current head model resolution. Additionally, the effect of anisotropy on EEG source analysis is investigated using realistic head model geometries and conductivities obtained from magnetic resonance images. It is determined that anisotropy should not be ignored since a significant amount of source localization error can occur.