Abstract：Magnetoencephalography (MEG) , as a new technology for non-invasive acquisition of brain signals, can accurately reflect the neural activity of the brain, however, traditional MEG equipment requires low-temperature superconducting environment and high operation and maintenance costs, which limit the development of this technology. Optically pumped magnetometer is a new type of magnetic field strength detection device that has many advantages including relatively low cost, high signal-to-noise ratio, no need for cryogenic liquid helium cooling, and are expected to promote MEG technology to wider applications. Based on the concept of MEG, this paper introduced the implementation principle of the optical-pump magnetometer-magnetic encephalography system from a technical point of view, clarifies the naming confusions that are existing in the system, and summarized the application and research progress of the system from several aspects including neural speech decoding, MEG source reconstruction, functional neuroimaging, brain-computer interface, and clinical assistance, meanwhile, summarized the unique advantages of the new MEG system. The potential application of this technology in the future was prospected, and the possible problems in the current research were analyzed and discussed.
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