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. 2014 Mar;17(Suppl 1):S107-12.
doi: 10.4103/0972-2327.128676.

Magnetoencephalography: Basic principles

Sanjay P Singh  1
Affiliations

Magnetoencephalography: Basic principles

Sanjay P Singh. Ann Indian Acad Neurol. 2014 Mar.

Abstract

Magnetoencephalography (MEG) is the measurement of the magnetic field generated by the electrical activity of neurons. It is usually combined with a magnetic resonance imaging to get what is called magnetic source imaging. The technology that has helped record these minute magnetic fields is super-conducting quantum interference detector which is like a highly sensitive magnetic field meter. To attenuate the external magnetic noise the MEG is housed inside a magnetically shielded room. The actual sensors recording magnetic fields are magnetometers and/or gradiometers. MEG fields pass through the head without any distortion. This is a significant advantage of MEG over electroencephalography. MEG provides a high spatial and temporal resolution. The recording and identification information should be according to the American Clinical Magnetoencephalography Society guidelines published in 2011. MEG currently has two approved indications in the United States, one is for pre-operative brain mapping and the other is for use in epilepsy surgery. MEG studies have shown functional brain tissue inside brain tumors.

Keywords: Cortical mapping; epilepsy; magnetic source imaging; magnetoencephalography.

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Conflict of interest statement

Conflict of Interest: Nil

Figures

Figure 1
Figure 1
Magnetoencephalography
Figure 2
Figure 2
Magnetoencephalography equipment (Hamalainen et al. Rev Mod Phys 1993)
Figure 3
Figure 3
Magnetoencephalography recording
Figure 4a and b
Figure 4a and b
Magnetic source imaging – Combining magnetoencephalography with magnetic resonance imaging
See this image and copyright information in PMC

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