Koles Z J
Department of Biomedical Engineering, University of Alberta, Edmonton, Canada.
Electroencephalogr Clin Neurophysiol. 1998 Feb;106(2):127-37. doi: 10.1016/s0013-4694(97)00115-6.
The concepts underlying the quantitative localization of the sources of the EEG inside the brain are reviewed along with the current and emerging approaches to the problem. The concepts mentioned include monopolar and dipolar source models and head models ranging from the spherical to the more realistic based on boundary and finite elements. The forward and inverse problems in electroencephalography are discussed, including the non-uniqueness of the inverse problem. The approaches to the solution of the inverse problem described include single and multiple time-slice localization, equivalent dipole localization and the weighted minimum norm. The multiple time-slice localization approach is highlighted as probably the best available at this time and is discussed in terms of the spatiotemporal model of the EEG. The effect of noise corruption, artifacts and the number of recording electrodes on the accuracy of source localization is also mentioned. It is suggested that the main appeal of the minimum norm is that it does not assume a model for the sources and provides an estimate of the current density everywhere in the three dimensional volume of the head.
本文回顾了脑电信号源在脑内定量定位的基本概念，以及针对该问题的现有和新兴方法。所提及的概念包括单极和偶极源模型，以及从球形到基于边界和有限元的更逼真的头部模型。文中讨论了脑电图中的正问题和逆问题，包括逆问题的非唯一性。所描述的逆问题解决方案包括单时间切片和多时间切片定位、等效偶极子定位以及加权最小范数法。多时间切片定位方法被强调为目前可能最好的方法，并根据脑电图的时空模型进行了讨论。文中还提到了噪声干扰、伪迹和记录电极数量对源定位准确性的影响。研究表明，最小范数法的主要吸引力在于它不假设源模型，并能对头三维体积内的电流密度进行估计。
