Minimum-Norm Source Estimation in MEG with Temporal Information
Sunao Iwaki, S. Ueno · Journal of the Magnetics Society of Japan · 1998
The weighted minimum-norm estimation (wMNE) is a popular method for obtaining the current distribution in the human brain from magnetic field measurement (magnetoencephalography: MEG) if detailed information about the generator profile is not available. However, because the conventional wMNE method deals only with instantaneous distribution of MEG data, the reconstructed current can be seriously distorted when the method is applied to noisy data. To reduce the distortion of the reconstructed current, a method is proposed for including temporal information from MEG data in the wMNE method, using MUSIC-like pre-scanning. Computer simulations of the proposed method and a comparison with the conventional wMNE method were performed. The results demonstrate that the proposed method is more effective than the conventional wMNE method for reconstructing the current distribution from noisy data.