F. Edelvik, B. Andersson, S. Jakobsson, S. Larsson,
M. Persson, and Y. Shirvany 

An improved method for dipole modeling in EEG-based source
localization

submitted to World Congress of Medical Physics and Biomedical
Engineering, 2009.


Abstract.  

The inverse problem in EEG-based source localization is to determine
the location of the brain sources that are responsible for the
measured potentials at the scalp electrodes.  The brain sources are
usually modeled as current dipoles which lead to a singularity in the
right-hand side of the governing Poisson's equation. Subtraction
methods have been proposed as a remedy and in this paper an improved
subtraction method for modeling the dipoles is presented. The accuracy
is demonstrated for radial and tangential sources in layered sphere
models and is to the best of the authors' knowledge superior to
previous methods for superficial sources. An additional advantage is
that it produces a right hand side with few non-zeros which is
beneficial for efficient solution of the inverse problem.

Keywords: epilepsy; EEG; finite element method; source reconstruction