A radial-basis function based surface Laplacian estimate for a realistic head model.

Yiran Zhai; Dezhong Yao

doi:10.1023/b:brat.0000047337.25591.32

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A radial-basis function based surface Laplacian estimate for a realistic head model.

Yiran Zhai·Dezhong Yao

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Abstract

Scalp surface Laplacian (SL) is widely used to enhance spatial resolution and sensitivity for electroencephalograph (EEG) recordings. In this paper, a radial-basis function (RBF) based surface Laplacian (RBFL) estimate is proposed for realistic head model, in which RBF is used as basis function to interpolate the surface of a head model and the surface potentials. The efficiency of RBFL was confirmed through a comparative study to the global realistic geometry spline Laplacian (GSL) with both simulation studies and human visual evoked potential. The simulations include both feasibility in a 3-concentric sphere head model and influence of head model noise and potential noise, effects of border source and sources separation distance in a realistic head model. All the comparisons show RBFL can provide comparatively better results than GSL and hence RBFL provide another efficient method for high-resolution EEG mapping.

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Algorithms Artifacts Brain Brain Mapping Electroencephalography Evoked Potentials, Visual Feasibility Studies Head Models, Anatomic Models, Neurological Normal Distribution Photic Stimulation Reaction Time Comparative Study Journal Article Research Support, Non-U.S. Gov't

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Yiran Zhai, Dezhong Yao. 2004. A radial-basis function based surface Laplacian estimate for a realistic head model.. https://doi.org/10.1023/b%3Abrat.0000047337.25591.32

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