Numerical approaches for dipole modeling in finite element method based source analysis
نویسندگان
چکیده
In EEG/MEG source analysis, a mathematical dipole is widely used as the “atomic” structure of the primary current distribution. When using realistic finite element models for the forward problem, the current dipole introduces a singularity on the right-hand side of the governing differential equation that has to be treated specifically. We evaluated and compared three different numerical approaches, a subtraction method, a direct approach using partial integration and a direct approach using the principle of Saint Venant. Evaluation and comparison were carried out in a fourlayer sphere model using quasi-analytical formulas. © 2007 Elsevier B.V. All rights reserved.
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