Letter | Published:

Moving magnetoencephalography towards real-world applications with a wearable system

Nature volume 555, pages 657661 (29 March 2018) | Download Citation

Abstract

Imaging human brain function with techniques such as magnetoencephalography1 typically requires a subject to perform tasks while their head remains still within a restrictive scanner. This artificial environment makes the technique inaccessible to many people, and limits the experimental questions that can be addressed. For example, it has been difficult to apply neuroimaging to investigation of the neural substrates of cognitive development in babies and children, or to study processes in adults that require unconstrained head movement (such as spatial navigation). Here we describe a magnetoencephalography system that can be worn like a helmet, allowing free and natural movement during scanning. This is possible owing to the integration of quantum sensors2,3, which do not rely on superconducting technology, with a system for nulling background magnetic fields. We demonstrate human electrophysiological measurement at millisecond resolution while subjects make natural movements, including head nodding, stretching, drinking and playing a ball game. Our results compare well to those of the current state-of-the-art, even when subjects make large head movements. The system opens up new possibilities for scanning any subject or patient group, with myriad applications such as characterization of the neurodevelopmental connectome, imaging subjects moving naturally in a virtual environment and investigating the pathophysiology of movement disorders.

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Acknowledgements

This study was funded by a Wellcome Collaborative Award in Science (203257/Z/16/Z and 203257/B/16/Z) awarded to G.R.B., R.B. and M.J.B. We also acknowledge the UK Quantum Technology Hub for Sensors and Metrology, funded by the Engineering and Physical Sciences Research Council (EP/M013294/1). We acknowledge Medical Research Council Grants (MR/K005464/1 and MR/M006301/1). The Wellcome Centre for Human Neuroimaging is supported by core funding from Wellcome (203147/Z/16/Z). OPM sensor development at QuSpin was supported by National Institutes of Health grants R44HD074495 and R44MH110288. The scanner-casts were designed and manufactured by M. Lim at Chalk Studios.

Author information

Author notes

    • Elena Boto
    • , Niall Holmes
    • , James Leggett
    •  & Gillian Roberts

    These authors contributed equally to this work.

    • Gareth R. Barnes
    • , Richard Bowtell
    •  & Matthew J. Brookes

    These authors jointly supervised this work.

Affiliations

  1. Sir Peter Mansfield Imaging Centre, School of Physics and Astronomy, University of Nottingham, University Park, Nottingham NG7 2RD, UK

    • Elena Boto
    • , Niall Holmes
    • , James Leggett
    • , Gillian Roberts
    • , Karen J. Mullinger
    • , Richard Bowtell
    •  & Matthew J. Brookes
  2. QuSpin Inc., 331 South 104th Street, Suite 130, Louisville, Colorado 80027, USA

    • Vishal Shah
  3. Wellcome Centre for Human Neuroimaging, UCL Institute of Neurology, University College London, 12 Queen Square, London WC1N 3BG, UK

    • Sofie S. Meyer
    • , Leonardo Duque Muñoz
    • , Tim M. Tierney
    • , Sven Bestmann
    •  & Gareth R. Barnes
  4. Institute of Cognitive Neuroscience, University College London, 17–19 Queen Square, London WC1N 3AZ, UK

    • Sofie S. Meyer
  5. Centre for Human Brain Health, School of Psychology, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK

    • Karen J. Mullinger
  6. Sobell Department for Motor Neuroscience and Movement Disorders, UCL Institute of Neurology, University College London, Queen Square House, Queen Square, London WC1N 3BG, UK

    • Sven Bestmann

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Contributions

E.B.: system design and fabrication, data collection, data analysis, data interpretation, writing paper. N.H.: system design and fabrication, data collection, data analysis, data interpretation, writing paper. J.L.: system design and fabrication, data collection, data analysis, data interpretation, writing paper. G.R.: system design and fabrication, data collection, data analysis, data interpretation, writing paper. V.S.: system design and fabrication. S.S.M.: data interpretation, writing paper. L.D.M.: data interpretation, writing paper. K.J.M.: data collection, data analysis, data interpretation, writing paper. T.M.T.: data interpretation, writing paper. S.B.: data collection, data interpretation, writing paper. G.R.B.: conceptualization, system design and fabrication, data interpretation, writing paper. R.B.: conceptualization, system design and fabrication, data collection, data analysis, data interpretation, writing paper. M.J.B.: conceptualization, system design and fabrication, data collection, data analysis, data interpretation, writing paper.

Competing interests

V.S. is the founding director of QuSpin, the commercial entity selling OPM magnetometers. QuSpin built the sensors used here and advised on the system design and operation, but played no part in the subsequent measurements or data analysis. This work was funded by a Wellcome award which involves a collaboration agreement with QuSpin.

Corresponding author

Correspondence to Matthew J. Brookes.

Reviewer Information Nature thanks S. Baillet and R. Leahy for their contribution to the peer review of this work.

Publisher's note: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Extended data

Supplementary information

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  1. 1.

    Life Sciences Reporting Summary

  2. 2.

    Supplementary Information

    This file contains: Trial-by-trial analysis of data; Spatiotemporal resolution and orientation robustness analysis; Evoked response analysis; Methods for OPM calibration to account for background fields; Discussion of the field nulling coil system; OPM MEG versus EEG comparison; Example applications in the measurement of brain connectivity; Simulation and experimental measurements of crosstalk between OPM sensors; Reduction of interference from muscle artifacts and Supplementary equipment schematics.

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DOI

https://doi.org/10.1038/nature26147

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