The future of MEG: Improved task-related responses using optically-pumped magnetometers compared to a conventional system

Abstract Optically-pumped magnetometers (OPMs) offer a new wearable means to measure magnetoencephalography (MEG) signals, with many advantages compared to conventional systems. However, OPMs are an emerging technology, thus characterizing and replicating MEG recordings is essential. Using OPM and cryogenic MEG, this study investigated evoked responses, oscillatory power, and functional connectivity during emotion processing in 21 adults, to establish replicability across the two technologies. Five participants with dental fixtures were included to assess the validity of OPM recordings in those with irremovable metal. Replicable task-related evoked responses were observed in both modalities, with the OPMs demonstrating higher peak amplitude and improved signal-to-noise. Similar patterns of oscillatory power to faces were observed in both systems. Increased connectivity was found in cryogenic versus OPM MEG in an occipital and parietal anchored network. Notably, high quality OPM data were retained in participants with metallic fixtures, from whom no useable data was collected using cryogenic MEG.