Riitta Hari a , * , Sylvain Baillet b , Gareth Barnes c , Richard Burgess d , Nina Forss e , Joachim Gross f , g , Matti Hämäläinen h , i , j , Ole Jensen k , Ryusuke Kakigi l , François Mauguière m , Nobukatzu Nakasato n , Aina Puce o , Gian-Luca Romani p , Alfons Schnitzler q , Samu Taulu r , s
1 August 2018
AEF, auditory evoked field, BOLD, blood-level oxygen dependent, CKC, corticokinematic coherence, CMC, cortex–muscle coherence, DCM, dynamic causal modeling, EEG, electroencephalography, ECD, equivalent current dipole, ECoG, electrocorticography, fMRI, functional magnetic resonance imaging, HE, hepatic encephalopathy, IAP, intracarotid amobarbital procedure, ICA, independent component analysis, IES, intracutaneous epidermal electrical stimulation, ISI, interstimulus interval, MEG, magnetoencephalography, MNE, minimum norm estimate, MRI, magnetic resonance imaging, MUSIC, multiple signal classification, SEF, somatosensory evoked field, SNR, signal-to-noise ratio, SQUID, superconducting quantum interference device, SSS, signal-space separation, STN, subthalamic nucleus, TMS, transcranial magnetic stimulation, tSSS, temporo-spatial signal space separation, VEF, visual evoked field, Magnetoencephalography, Electroencephalography, Clinical neurophysiology, Evoked and event-related responses, Transient and steady-state responses, Spontaneous brain activity, Neural oscillations, Analysis and interpretation, Artifacts, Source modeling, Epilepsy, Preoperative evaluation, Stroke, Pain, Traumatic brain injury, Parkinson’s disease, Hepatic encephalopathy, Alzheimer’s disease and dementia, Neuropsychiatric disorders, Brain maturation and development, Dyslexia, Guidelines
Magnetoencephalography (MEG) records weak magnetic fields outside the human head and thereby provides millisecond-accurate information about neuronal currents supporting human brain function. MEG and electroencephalography (EEG) are closely related complementary methods and should be interpreted together whenever possible.
This manuscript covers the basic physical and physiological principles of MEG and discusses the main aspects of state-of-the-art MEG data analysis. We provide guidelines for best practices of patient preparation, stimulus presentation, MEG data collection and analysis, as well as for MEG interpretation in routine clinical examinations.
In 2017, about 200 whole-scalp MEG devices were in operation worldwide, many of them located in clinical environments. Yet, the established clinical indications for MEG examinations remain few, mainly restricted to the diagnostics of epilepsy and to preoperative functional evaluation of neurosurgical patients. We are confident that the extensive ongoing basic MEG research indicates potential for the evaluation of neurological and psychiatric syndromes, developmental disorders, and the integrity of cortical brain networks after stroke. Basic and clinical research is, thus, paving way for new clinical applications to be identified by an increasing number of practitioners of MEG.