Influence of tissue conductivity anisotropy on EEG/MEG field and return current computation in a realistic head model: A simulation and visualization study using high-resolution finite element modeling

被引:318
作者
Wolters, CH
Anwander, A
Tricoche, X
Weinstein, D
Koch, MA
MacLeod, RS
机构
[1] Univ Munster, Inst Biomagnetismus & Biosignalanalyse, D-48149 Munster, Germany
[2] Univ Utah, Sci Comp & Imaging Inst, Salt Lake City, UT 84112 USA
[3] Max Planck Inst Human Cognit & Brain Sci, D-04103 Leipzig, Germany
[4] Univ Hamburg, Med Ctr, Dept Syst Neurosci, D-20246 Hamburg, Germany
[5] Univ Utah, Nora Eccles Harrison Cardiovasc Res & Training In, CVRTI, Dept Bioengn, Salt Lake City, UT 84112 USA
关键词
EEG; MEG; source reconstruction; tissue conductivity anisotropy; CSF; forward problem; finite element method; return current; visualization;
D O I
10.1016/j.neuroimage.2005.10.014
中图分类号
Q189 [神经科学];
学科分类号
071006 ;
摘要
To achieve a deeper understanding of the brain, scientists, and clinicians use electroencephalography (EEG) and magnetoencephalography (MEG) inverse methods to reconstruct sources in the cortical sheet of the human brain. The influence of structural and electrical anisotropy in both the skull and the white matter on the EEG and MEG source reconstruction is not well understood. In this paper, we report on a study of the sensitivity to tissue anisotropy of the EEG/MEG forward problem for deep and superficial neocortical sources with differing orientation components in an anatomically accurate model of the human head. The goal of the study was to gain insight into the effect of anisotropy of skull and white matter conductivity through the visualization of field distributions, isopotential surfaces, and return current flow and through statistical error measures. One implicit premise of the study is that factors that affect the accuracy of the forward solution will have at least as strong an influence over solutions to the associated inverse problem. Major findings of the study include (1) anisotropic white matter conductivity, causes return currents to flow in directions parallel to the white matter fiber tracts; (2) skull anisotropy has a smearing effect on the forward potential computation; and (3) the deeper a source lies and the more it is surrounded by anisotropic tissue, the larger the influence of this anisotropy on the resulting electric and magnetic fields. Therefore, for the EEG, the presence of tissue anisotropy both for the skull and white matter compartment substantially compromises the forward potential computation and as a consequence, the inverse source reconstruction. in contrast, for the MEG, only the anisotropy of the white matter compartment has a significant effect. Finally, return currents with high amplitudes were found in the highly conducting cerebrospinal fluid compartment, underscoring the need for accurate modeling of this space. (c) 2005 Elsevier Inc. All rights reserved.
引用
收藏
页码:813 / 826
页数:14
相关论文
共 59 条
[1]   Conductivities of three-layer live human skull [J].
Akhtari, M ;
Bryant, HC ;
Marnelak, AN ;
Flynn, ER ;
Heller, L ;
Shih, JJ ;
Mandelkern, M ;
Matlachov, A ;
Ranken, DM ;
Best, ED ;
DiMauro, MA ;
Lee, RR ;
Sutherling, WW .
BRAIN TOPOGRAPHY, 2002, 14 (03) :151-167
[2]  
ANWANDER A, NEUROFEM 2000 2005 P
[3]  
Anwander A., 2002, P 13 INT C BIOM, P679
[4]  
ANWANDER A, IN PRESS INFLUENCE R
[5]   MR DIFFUSION TENSOR SPECTROSCOPY AND IMAGING [J].
BASSER, PJ ;
MATTIELLO, J ;
LEBIHAN, D .
BIOPHYSICAL JOURNAL, 1994, 66 (01) :259-267
[6]  
Basser PJ, 1996, J MAGN RESON SER B, V111, P209, DOI [10.1006/jmrb.1996.0086, 10.1016/j.jmr.2011.09.022]
[7]   ESTIMATION OF THE EFFECTIVE SELF-DIFFUSION TENSOR FROM THE NMR SPIN-ECHO [J].
BASSER, PJ ;
MATTIELLO, J ;
LEBIHAN, D .
JOURNAL OF MAGNETIC RESONANCE SERIES B, 1994, 103 (03) :247-254
[8]   The electrical conductivity of human cerebrospinal fluid at body temperature [J].
Baumann, SB ;
Wozny, DR ;
Kelly, SK ;
Meno, FM .
IEEE TRANSACTIONS ON BIOMEDICAL ENGINEERING, 1997, 44 (03) :220-223
[9]  
*BIOPSE, 2002, PROBL SOLV ENV MOD S
[10]  
Bruno P, 2004, P 26 ANN INT C IEEE