Magnetoencephalography with optically pumped magnetometers (OPM-MEG): studying brain activity in neurological patients while standing

<h3></h3> Gait and balance disturbances play an important role in the quality of life, morbidity and mortality of patients with neurological diseases. The critical limitation of neuroimaging studies of gait and balance disorders, so far, has been the required decubitus position. OPM-MEG is a technological advance in magnetoencephalography (MEG) that offers improved signal sensitivity and spatial resolution, especially for cortical networks. Crucially for study of gait and balance, OPM-MEG allows scanning whilst participants stand and move. Here, as a proof of principle that this novel technology can be used in patients, we deployed a novel 192- channel OPM-MEG system (with unique triaxial design and a novel matrix coil) to study 7 patients with multiple sclerosis and 11 controls performing motor and visual tasks while sitting and standing. All patients were able to undertake the recordings, and analysis generated accurate localisation of neuronal processes. Results show, for the first time, that it is feasible to study brain function with high spatial resolution in patients with neurological diseases while standing up. We posit that OPM-MEG will become a useful instrument to study focal, regional and distributed network dysfunction in conditions that affect gait, whereas other imaging modalities cannot be considered for such naturalistic tasks.