DEEI, University of Trieste, Via A. Valerio 10, 34127 Trieste, Italy.
Comput Intell Neurosci. 2010;2010:972060. doi: 10.1155/2010/972060. Epub 2010 Feb 14.
The accuracy of forward models for electroencephalography (EEG) partly depends on head tissues geometry and strongly affects the reliability of the source reconstruction process, but it is not yet clear which brain regions are more sensitive to the choice of different model geometry. In this paper we compare different spherical and realistic head modeling techniques in estimating EEG forward solutions from current dipole sources distributed on a standard cortical space reconstructed from Montreal Neurological Institute (MNI) MRI data. Computer simulations are presented for three different four-shell head models, two with realistic geometry, either surface-based (BEM) or volume-based (FDM), and the corresponding sensor-fitted spherical-shaped model. Point Spread Function (PSF) and Lead Field (LF) cross-correlation analyses were performed for 26 symmetric dipole sources to quantitatively assess models' accuracy in EEG source reconstruction. Realistic geometry turns out to be a relevant factor of improvement, particularly important when considering sources placed in the temporal or in the occipital cortex.
脑电图（EEG）正向模型的准确性部分取决于头部组织的几何形状，并且强烈影响源重建过程的可靠性，但目前尚不清楚哪些脑区对不同模型几何形状的选择更为敏感。在本文中，我们比较了不同的球形和真实头部建模技术，这些技术用于从分布在基于蒙特利尔神经学研究所（MNI）MRI 数据重建的标准皮质空间上的电流偶极子源估算 EEG 正向解。为三个不同的四壳头部模型（两个具有真实几何形状，基于表面（BEM）或基于体积（FDM））和相应的传感器拟合球形模型展示了计算机模拟。点扩散函数（PSF）和导联场（LF）的互相关分析针对 26 个对称偶极子源进行，以定量评估模型在 EEG 源重建中的准确性。真实的几何形状是改进的一个相关因素，特别是在考虑放置在颞叶或枕叶皮质的源时更为重要。
