Improved accuracy of MEG localization in the temporal region with inclusion of volume current effects

Abstract
We studied the magnetic field maps generated by six dipoles in the temporal region of a plastic skull filled with conducting gel. The data were processed with two mathematical models. One, using Biot-Savart's law, considered only the magnetic field generated by a localized current dipole, and the other considered a dipole in a sphere and included volume current effects. The contribution of volume current effects to the MEG maps was significant. The localizing capability of MEG improved from an average distance of 2.9 cm to 0.9 cm when volume current effects were considered.