Development of realistic head models for electromagnetic source imaging of the human brain

Akahn, Z.
Acar, C.E.
Gençer, Nevzat Güneri
In this work, a methodology is developed to solve the forward problem of electromagnetic source imaging using realistic head models. For this purpose, first segmentation of the 3 dimensional MR head images is performed. Then triangular, quadratic meshes are formed for the interfaces of the tissues. Thus, realistic meshes, representing scalp, skull, CSF, brain and eye tissues, are formed. At least 2000 nodes for the scalp and 5000 for the cortex are needed to obtain reasonable geometrical approximation. Solution of the forward problem using our previous Boundary Element Method (BEM) formulation with quadratic elements remains to be made.


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Akalm, Z; Gençer, Nevzat Güneri (2003-09-21)
In this study, the forward problem of electrical source imaging (ESI) is solved using the Boundary Element method (BEM) with realistic head models. The realistic model consists of scalp, skull, CSF, brain and eyes. To get more accurate results quadratic elements are used in the meshes-and a new method is proposed for the generation of the quadratic mesh. An accelerated method is proposed for the solution of the potential field.
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Solution of the Electro-Magnetic Source Imaging (EMSI) problem requires an accurate representation of the head using a numerical model. Some of the errors in source estimation are due to the differences between this model and the actual head. This study investigates the effects of conductivity perturbations, that is, changing the conductivity of a small region by a small amount, on the EEG and MEG measurements. By computing the change in measurements for perturbations throughout the volume, it is possible t...
Citation Formats
Z. Akahn, C. E. Acar, and N. G. Gençer, “Development of realistic head models for electromagnetic source imaging of the human brain,” 2002, Accessed: 00, 2020. [Online]. Available: