The electrophysiological activities in the human body generate electric and magnetic fields that can be measured noninvasively by electrodes on the skin, or even, not requiring any contact, by magnetometers. This includes the measurement of electrical activity of brain, heart, muscles and nerves that can be measured in vivo and allows to analyze functional processes with high temporal resolution. To measure these extremely small magnetic biosignals, traditionally highly sensitive superconducting quantum-interference devices have been used, together with advanced magnetic shields. Recently, they have been complemented in usability by a new class of sensors, optically pumped magnetometers (OPMs). These quantum sensors offer a high sensitivity without requiring cryogenic temperatures, allowing the design of small and flexible sensors for clinical applications. In this letter, we describe the advantages of these upcoming OPMs in two exemplary applications that were recently carried out at Physikalisch-Technische Bundesanstalt (PTB): (1) magnetocardiography (MCG) recorded during exercise and (2) auditory-evoked fields registered by magnetoencephalography.
Funding source: European Metrology Programme for Innovation and Research (EMPIR)10.13039/100014132
Award Identifier / Grant number: 15HLT03 EARS II
The authors are indebted to Lutz Trahms for long lasting support and collaboration.
Author contribution: All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.
Research funding: Financial support from the European Metrology Research Programme (EMPIR, “Health” program, grant no. 15HLT03 EARS II) is gratefully acknowledged. The EMPIR is jointly funded by the EMPIR participating countries within EURAMET and the European Union.
Conflict of interest statement: The authors declare no conflicts of interest regarding this article.
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