【摘要】 从算法的精度、效率和复杂性3个方面对三维各向同性脑电正问题求解中的有限元法(FEM)和有限差分法(FDM)进行了比较,分别采用三层同心球模型和偶极子源模拟具有3种组织的头和大脑活动神经元,研究了头模型的网格细化程度、对称性和偶极子源方向、偏心率对有限差分法和有限元法精度和效率的影响.仿真计算结果表明,有限元法的精度易受切向偶极子的影响,而有限差分法的精度易受径向偶极子的影响,在相同的网格细化程度下,两种算法需要同样的耗机时间;由于有限元法精度易受网格模型对称性的影响,有限差分法的真实头模型网格构建比有限元法简单、直观.更多还原

【Abstract】 Finite element method(FEM) and finite difference method(FDM) were compared for resolution of 3D isotropic eletroencephalogram forward problem,from the point of view of computational accuracy,efficiency and complexity.Three-concentric-sphere model and current dipole were used to simulate the head volume conductor and brain electrical activity,respectively.The effects of dipole eccentricity and grid model size on the solution accuracy and efficiency were addressed.Simulation indicates that the numerical accuracy of FEM is more sensitive to tangential dipoles,while FDM is more sensitive to radial dipoles,and FEM provides similar computational efficiency as FDM for equivalent number of elements.The reconstruction of grid model for FEM is more complex than for FDM,especially to reconstruct the realistic head model.更多还原