Dipole Localization Errors Due to Not Incorporating Anisotropic Conductivities in Realistic Headmodels
نویسنده
چکیده
Many source localization methods neglect the anisotropic conductivity of brain tissues, although it has a big influence on the localization problem. In this study, we evaluated the dipole localization error due to neglecting the anisotropic properties of the conductivity in a realistic head model (built from T1 and diffusion tensor MRI) calculated using a FDM method. Results show that the mean dipole localization was on average 9.3 mm. Moreover the large errors were found te be at the edge of the soft brain tissues. We therefore conclude that the incorporation of anisotropic conductivity is necessary for an accurate localization of the dipole.
منابع مشابه
A finite difference method with reciprocity used to incorporate anisotropy in electroencephalogram dipole source localization.
Many implementations of electroencephalogram (EEG) dipole source localization neglect the anisotropical conductivities inherent to brain tissues, such as the skull and white matter anisotropy. An examination of dipole localization errors is made in EEG source analysis, due to not incorporating the anisotropic properties of the conductivity of the skull and white matter. First, simulations were ...
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