Magnetoencephalography

Magnetoencephalography
Name	Magnetoencephalography
Uses	Functional neuroimaging
Inventor	David Cohen
Year	1968
Fields	Neurology; Neuroscience; Cognitive science

Magnetoencephalography Magnetoencephalography is a noninvasive functional neuroimaging technique that records magnetic fields produced by neuronal currents, offering millisecond temporal resolution for brain dynamics. Developed from advances in superconducting sensors and signal processing, it complements techniques associated with Louis Pasteur, Marie Curie, Leonardo da Vinci, Max Planck and institutions such as Massachusetts Institute of Technology, University of California, Berkeley, Harvard University, University College London and Karolinska Institutet. Clinical and research centers including Mayo Clinic, Johns Hopkins Hospital, Stanford University, University of Oxford and University of Toronto have established notable programs integrating this modality.

Introduction

The method maps neuronal activity by detecting extracranial magnetic fields using arrays of superconducting quantum interference devices pioneered by researchers connected to David Cohen, James L. McGaugh, Roger Sperry, Paul G. Allen, and laboratories at Bell Labs, Brookhaven National Laboratory, Los Alamos National Laboratory, Max Planck Society and Los Alamos National Laboratory. Applications span investigations at centers like National Institutes of Health, Wellcome Trust Centre for Neuroimaging, Karolinska University Hospital, Routine Hospital, Seoul National University Hospital and collaborations with teams from European Space Agency, National Aeronautics and Space Administration, Chinese Academy of Sciences, Riken, and Swiss Federal Institute of Technology Zurich.

History and development

Early magnetic measurements trace to work influenced by figures such as Hans Christian Ørsted, Michael Faraday, James Clerk Maxwell, Heinrich Hertz, Nikola Tesla, Ernest Rutherford and laboratory environments like CERN, Los Alamos National Laboratory, Rutherford Appleton Laboratory, Riken Center, Lawrence Livermore National Laboratory and Stanford Linear Accelerator Center. The first human recordings emerged in settings associated with David Cohen and subsequent instrumentation advances involved collaborations with companies and institutions including BTG plc, Siemens, Elekta, General Electric, Philips, IBM, Hitachi, Nippon Telegraph and Telephone, Tokyo Institute of Technology, Imperial College London, University of Cambridge, Columbia University, Yale University and University of Chicago.

Principles and instrumentation

Detection relies on neurophysiological currents in cortical pyramidal neurons and on magnetic sensing technologies developed alongside breakthroughs linked to Brian Josephson, John Bardeen, Walter Brattain, Leo Esaki, Herbert Kroemer and manufacturing by firms connected to Fujitsu, NEC Corporation, Hitachi, Elekta and Siemens Healthcare. Core instruments combine helmet-shaped sensor arrays with magnetically shielded rooms built by engineering teams from Honeywell, Thales Group, Lockheed Martin, Raytheon Technologies and materials science input from DuPont, 3M, Boeing and General Dynamics. Sensor technologies include low-temperature SQUIDs influenced by work at Bell Labs, and emerging optically pumped magnetometers with research from National Institute of Standards and Technology, University of Tokyo, Peking University, ETH Zurich and University of California, San Diego.

Data acquisition and analysis

Acquisition protocols are standardized in clinical centers such as Mayo Clinic, Cleveland Clinic, Massachusetts General Hospital, Sheffield Teaching Hospitals, Karolinska University Hospital and computational pipelines draw on algorithms and frameworks developed by groups at MIT, Google DeepMind, Facebook AI Research, Microsoft Research, University of Cambridge, University College London and Princeton University. Analysis uses inverse problem solutions, beamforming, source localization and time–frequency decomposition methods with software toolboxes originating from FMRIB Centre, SPM (software), FieldTrip, MNE-Python, EEGLAB, AFNI, Neuroimaging Informatics Tools and Resources Clearinghouse and collaborations with teams at Centre National de la Recherche Scientifique, Max Planck Institute for Human Cognitive and Brain Sciences, Riken Brain Science Institute, Weizmann Institute of Science and Australian National University.

Clinical and research applications

Clinically, it informs pre-surgical mapping, epilepsy localization and language lateralization at centers such as Cleveland Clinic, Johns Hopkins Hospital, Mayo Clinic, Mount Sinai Health System, Toronto Western Hospital, Guy's and St Thomas' NHS Foundation Trust and research into cognition, perception, memory and attention conducted by investigators tied to Stanford University, University of California, Berkeley, Princeton University, Harvard University, Yale University, University of Oxford, Columbia University, University of Pennsylvania, Brown University and Duke University. Studies linking patient cohorts from National Institutes of Health projects, European Research Council grants, Wellcome Trust fellowships and partnerships with National Health Service hospitals have explored development, psychiatric conditions and neurodegenerative disorders with collaboration from Alzheimer's Association, Michael J. Fox Foundation, Parkinson's UK, American Epilepsy Society, International League Against Epilepsy, World Health Organization and United Nations Educational, Scientific and Cultural Organization.

Advantages, limitations, and safety

Advantages are emphasized in reports from National Institutes of Health, Wellcome Trust, US Food and Drug Administration, European Medicines Agency, World Health Organization and research units at Massachusetts General Hospital and Johns Hopkins Hospital for temporal precision and direct neuronal sensitivity, while limitations include sensitivity to superficial sources and shielding requirements discussed by engineers at Thales Group, Siemens, Elekta and material scientists at DuPont, 3M and Tokyo Institute of Technology. Safety and regulatory considerations are overseen by agencies including US Food and Drug Administration, European Medicines Agency, Health Canada, Australian Therapeutic Goods Administration and institutional review boards at Harvard Medical School, University of Toronto Faculty of Medicine, Karolinska Institutet and Oxford University Hospitals NHS Foundation Trust.

Future directions and innovations

Future work involves portable and optically pumped magnetometer systems developed at NIST, Imperial College London, University of Maryland, University of California, Berkeley and Riken, integration with multimodal platforms at Stanford Neurosciences Institute, McGovern Institute for Brain Research, Wellcome Centre for Human Neuroimaging, Allen Institute for Brain Science and AI-driven analysis from DeepMind, OpenAI, IBM Research and Microsoft Research. Large-scale projects and consortia including Human Brain Project, BRAIN Initiative, European Research Council, Horizon 2020 and collaborations with Gates Foundation, Chan Zuckerberg Initiative, WHO and NIH BRAIN Initiative aim to expand accessibility, standardization and translational impact.

Category:Neuroimaging