Non-Invasive Functional-Brain-Imaging with an OPM-based Magnetoencephalography System

Autoři: Amir Borna aff001;  Tony R. Carter aff001;  Anthony P. Colombo aff001;  Yuan-Yu Jau aff001;  Jim McKay aff002;  Michael Weisend aff003;  Samu Taulu aff004;  Julia M. Stephen aff005;  Peter D. D. Schwindt aff001
Působiště autorů: Sandia National Laboratories, Albuquerque, NM, United States of America aff001;  Candoo Systems Inc., Coquitlam, BC, Canada aff002;  StimScience, Inc., Berkeley, CA, United States of America aff003;  University of Washington Seattle, Seattle, WA, United States of America aff004;  The Mind Research Network and Lovelace Biomedical and Environmental Research Institute, Albuquerque, NM, United States of America aff005
Vyšlo v časopise: PLoS ONE 15(1)
Kategorie: Research Article


A non-invasive functional-brain-imaging system based on optically-pumped-magnetometers (OPM) is presented. The OPM-based magnetoencephalography (MEG) system features 20 OPM channels conforming to the subject’s scalp. We have conducted two MEG experiments on three subjects: assessment of somatosensory evoked magnetic field (SEF) and auditory evoked magnetic field (AEF) using our OPM-based MEG system and a commercial MEG system based on superconducting quantum interference devices (SQUIDs). We cross validated the robustness of our system by calculating the distance between the location of the equivalent current dipole (ECD) yielded by our OPM-based MEG system and the ECD location calculated by the commercial SQUID-based MEG system. We achieved sub-centimeter accuracy for both SEF and AEF responses in all three subjects. Due to the proximity (12 mm) of the OPM channels to the scalp, it is anticipated that future OPM-based MEG systems will offer enhanced spatial resolution as they will capture finer spatial features compared to traditional MEG systems employing SQUIDs.

Klíčová slova:

Head – Lasers – Magnetic fields – Magnetic resonance imaging – Magnetoencephalography – Magnetometers – Scalp – Vapors


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