脑白质非均质电导率特性对脑电正问题影响的仿真研究

Effects investigation of white matter inhomogeneous conductivity on EEG forward solutions

通过在真实头模型上进行仿真研究,采用有限差分法求解人脑深部灰质和浅处皮层上的脑电源在头皮表面产生的电位分布,分别讨论了两种不同的白质组织非均质电导率特性对脑电正问题的影响.仿真研究结果表明,脑电源在大脑中的位置越深,头皮电位分布受脑白质非均质的影响越大.脑白质电导率各向异性非均质对头皮电位分布具有一定的影响.

The present simulation work was accomplished through the realistic head volume conductor with two kinds of inhomogeneous and anisotropic White Matter （WM） conductivities estimated by the volume constraint method. The finite difference method （FDM） was used to estimate the current dipole, which was used to simulate the brain electrical activity with varying locations and orientations within the Gray Matter （GM） of the cortex. The influence of the three different WM conductivities characteristics on the electroencephalogram （EEG） forward problem was studied based on the simulation results. The deeper the dipole was located, the larger the imposed effect was. The anisotropic conductivity of WM may have some effects on the scalp EEG.