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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Zhai, Y., Yao, D. A Radial-Basis Function Based Surface Laplacian Estimate for a Realistic Head Model. Brain Topogr 17, 55–62 (2004). https://doi.org/10.1023/B:BRAT.0000047337.25591.32
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DOI: https://doi.org/10.1023/B:BRAT.0000047337.25591.32