Abstract
Purpose
In this paper, we investigated the influence of orientation and activation area of extended cortical current sources upon the solutions of magnetoencephalography (MEG) inverse problems.
Methods
Extensive simulation studies were performed with artificial MEG datasets generated using a realistic head geometry model.
Results
Our simulation studies demonstrated that as the source activation area was extended beyond a threshold level, the radial component of cortical sources was weakened and thus the accuracy of MEG inverse problem was enhanced.
Conclusions
These are important findings suggesting that one may not need to be concerned too much about the insensitivity of MEG to radial sources in many practical MEG measurements.
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Choi, JH., Luan, F., Kim, MH. et al. Influence of orientation and area of the extended cortical current source on the magnetoencephalography (MEG) inverse problem. Biomed. Eng. Lett. 2, 124–128 (2012). https://doi.org/10.1007/s13534-012-0061-z
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DOI: https://doi.org/10.1007/s13534-012-0061-z