Visualization of Magnetoencephalographic Data Using Minimum Current Estimates

doi:10.1006/nimg.1999.0454

NeuroImage

Volume 10, Issue 2, August 1999, Pages 173-180

https://doi.org/10.1006/nimg.1999.0454 Get rights and content

Abstract

The locations of active brain areas can be estimated from the magnetic field the neural current sources produce. In this work we study a visualization method of magnetoencephalographic data that is based on minimum ℓ¹-norm estimates. The method can represent several local or distributed sources and does not need explicit a priori information. We evaluated the performance of the method using simulation studies. In a situation resembling typical magnetoencephalographic measurement, the mean estimated source strength exceeded baseline level up to 2 cm from the simulated point-like source. The method can also visualize several sources, activated simultaneously or in a sequence, which we demonstrated by analyzing magnetic responses associated with sensory stimulation and a picture naming task.

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Regular ArticleVisualization of Magnetoencephalographic Data Using Minimum Current Estimates

Abstract

Electroenceph. Clin. Neurophysiol.

Int. J. Psychophysiol.

Neurosci. Lett.

A 122-channel SQUID instrument for investigating the magnetic signals from the human brain

Phys. Scripta

On minimal ℓp-norm solutions of the biomagnetic inverse problem

IEEE Trans. Biomed. Eng.

Somatically evoked magnetic fields of the human brain

Science

Spatio-temporal localization of cortical word repetition effects in a size judgment task using combined fMRI/MEG

NeuroImage

Improved localization of cortical activity by combining EEG and MEG with MRI cortical surface reconstruction: A linear approach

J. Cogn. Neurosci.

A random dipole model for spontaneous brain activity

IEEE Trans. Biomed. Eng.

Activation of the human posterior parietal cortex by median nerve stimulation

Exp. Brain Res.