Design of locally arranged sensor arrays in wearable OPM-MEG based on sensor volume constraints

• Published in: Measurement : journal of the International Measurement Confederation 2024-04, Vol.229, p.114373, Article 114373
• Main Authors: Wang, Wenli, Cao, Fuzhi, An, Nan, Li, Wen, Xu, Weinan, Wang, Chunhui, Gao, Zhenfeng, Yu, Dexin, Gao, Yang, Ning, Xiaolin
• Format: Article
• Language: English
• Subjects: Flexible helmet; Locally arranged sensor array; Magnetoencephalography; OPM-MEG; Source localization
• ISSN: 0263-2241; 1873-412X
• DOI: 10.1016/j.measurement.2024.114373

•A LASAs design method based on sensor volume constraints is proposed.•LASAs can reduce source localization errors and concentrate the localization range of the target source region.•A wearable OPM-MEG system based on LASAs is constructed.•Customizing LASAs available for different measurement requirements. Optically pumped magnetometers-based magnetoencephalography (OPM-MEG) has a more flexible sensor configuration. This implies that OPM-MEG can be customized as locally arranged sensor arrays (LASAs) when the number of sensors is limited. Currently, various methods are proposed to optimize LASA for accurately estimating source currents. However, the sensor volume, as a practical constraint in the construction of an OPM-MEG system, was not taken into account during the design of sensor arrays. In this study, we proposed a sensor-array design method for LASAs that considers the physical size of OPM sensors, with the array sensitivity metrics serving as the optimization objective. To illustrate the effectiveness of the proposed method, several LASAs covering typical brain functional regions were designed and tested in both simulations and practical OPM-MEG experiments. The results indicated that the designed LASAs under sensor volume constraints demonstrated reduced source localization errors and focused localization range for the target source area.