Lightweight and wearable magnetoencephalography system based on spatially-grid constrained coils and compact magnetically shielded room

• Published in: NeuroImage (Orlando, Fla.) Fla.), 2024-10, Vol.300, p.120842, Article 120842
• Main Authors: Dou, Shuai, Liu, Xikai, Deng, Ya, Chen, Yimin, Song, Pengfei, Wen, Tong, Han, Bangcheng
• Format: Article
• Language: English
• Subjects: Active–passive coupling magnetic shielding strategy; Induced brain magnetic signals measurement; Magnetic fields; Magnetoencephalography; Motor task performance; Neurodevelopmental disorders; Neuroimaging; Occipital lobe; Spatially-grid constrained coil; Ultra-high space utilization ratio
• ISSN: 1053-8119; 1095-9572; 1095-9572
• DOI: 10.1016/j.neuroimage.2024.120842

Magnetoencephalography based on optically pumped magnetometers can passively detect the ultra-weak brain magnetic field signals, which has significant clinical application prospects for the diagnosis and treatment of cerebral disorders. This paper proposes a brain magnetic signal measurement method on the basis of the active–passive coupling magnetic shielding strategy and helmet-mounted detection array, which has lower cost and comparable performance over the existing ones. We first utilized the spatially-grid constrained coils and biplanar coils with proportion–integration–differentiation controller with tracking differentiator to ensure a near-zero and stable magnetic field environment with large uniform region. Subsequently, we implemented the brain magnetic signal measurement with the subject randomly moving fingers through tapping a keyboard and with the condition of opening and closing the eyes. Effectively induced brain magnetic signals were detected at the motor functional area and occipital lobe area in the two experiments, respectively. The proposed method will contribute to the development of functional brain imaging. •The active–passive coupling magnetic shielding system is designed to create a large uniform region near-zero magnetic field environment.•A method for the design and simplification of the spatially-grid constrained coils is proposed.•The induced brain magnetic signals at the motor functional area and occipital lobe area were successfully detected.•The proposed method will contribute to the development of lightweight wearable MEG system and functional brain imaging.