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An efficient algorithm for computing multishell spherical volume conductor models in EEG dipole source localization.

M Sun
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Abstract

Computationally localizing electrical current sources of the electroencephalographic signal requires a volume conductor model which relates theoretical scalp potentials to the dipolar source located within the modeled brain. The commonly used multishell spherical model provides this source-potential relationship using a sum of infinite series whose computation is difficult. This paper provides a closed-form approximation to this sum based on an optimal fitting to the weights of the Legendre polynomials. The second-order (third-order) approximation algorithm, implemented by a provided C-routine, requires only 100 (140) floating point operations to compute a single scalp potential in response to an arbitrary current dipole located within a four-shell spherical volume conductor model. This cost of computation represents only 6.3% (8.9%) of that required by the direct method. The relative mean square error, measured by using 20,000 random dipoles distributed within the modeled brain, in only 0.29% (0.066%).

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AlgorithmsBrainComputer SimulationCosts and Cost AnalysisElectroencephalographyElectrophysiologyHeadHumansModels, NeurologicalScalpJournal ArticleResearch Support, Non-U.S. Gov't

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BibTeXRIS

M Sun. 1997. An efficient algorithm for computing multishell spherical volume conductor models in EEG dipole source localization.. https://doi.org/10.1109/10.649996

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