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Updated: Aug 16, 2026

Mapping Cortical Dynamics Using Simultaneous MEG/EEG and Anatomically-constrained Minimum-norm Estimates: an Auditory Attention Example
Published on: October 24, 2012
Magnetic source images determined by a lead-field analysis: the unique minimum-norm least-squares estimation
J Z Wang1, S J Williamson, L Kaufman
1Neuromagnetism Laboratory, Department of Physics, New York University, NY 10003.
Abstract:
The minimum norm least-squares approach based on lead field theory provides a unique inverse solution for a magnetic source image that is the best estimate in the least-squares sense. This has been applied to determine the source current distribution when the primary current is confined to a surface or set of surfaces. In model simulations of cortical activity of the human brain, the magnetic field pattern across the scalp is interpreted with prior knowledge of anatomy to yield a unique magnetic source image across a portion of cerebral cortex, without resort to an explicit source model.
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