A wearable functional-brain-imaging system with full-head coverage and enhanced spatiotemporal-resolution to study complex neural circuits in human subjects

一种可穿戴的功能性大脑成像系统，具有全头部覆盖和增强的时空分辨率，用于研究人类受试者的复杂神经回路

• 批准号: 10697355
• 负责人: Peter D. D. Schwindt
• 金额: $ 102.56万
• 依托单位: SANDIA CORP-SANDIA NATIONAL LABORATORIES
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-09-21 至 2025-05-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10697355
• 关键词: Adult; Auditory area; Brain; Brain imaging; Brain region; Calibration; Cerebellum; Child; Communication; Compensation; Complex; Computer software; Cortical Column; Development; Discrimination; Electroencephalography; Electronics; Environment; Epilepsy; Evaluation; Frequencies; Functional Magnetic Resonance Imaging; Goals; Grant; Head; Helmet; Human; Image; Individual; Lasers; Location; Magnetism; Magnetoencephalography; Maps; Measurement; Measures; Methods; Modeling; Monitor; Morphologic artifacts; Movement; Neurons; Neurosciences; Noise; Optics; Performance; Persons; Physics; Positioning Attribute; Premature Infant; Pump; Resolution; Rest; Saccades; Sampling; Scalp structure; Shapes; Signal Transduction; Somatosensory Cortex; Source; Structure; Subject Headings; Support System; System; Techniques; Technology; Temperature; Time; United States National Institutes of Health; Validation; Visual Cortex; advanced system; aged; clinical application; cortex mapping; cost; cranium; cryogenics; data acquisition; density; design; experimental study; human subject; imaging approach; imaging modality; imaging system; improved; magnetic field; millimeter; millisecond; neural; neural circuit; neuroimaging; neuronal circuitry; operation; prototype; scale up; sensor; signal processing; simulation; spatiotemporal; superconducting quantum interference device; temporal measurement; tool; usability; vector

PROJECT SUMMARY/ABSTRACT To develop maps at multiple scales of neuronal circuits in the human brain and study the brain dynamics, there is a need for non-invasive functional brain imaging with high spatiotemporal resolution operating in natural environments. Among non-invasive functional brain imaging methods, magnetoencephalography (MEG) is the only technology that can map cortical activity down to millimeter spatial resolution with millisecond time resolution. Current cryogenic MEG systems employ superconducting quantum interference device (SQUID) magnetometers. The cryogenic operation requires sensor arrays that are rigid and fixed in a helmet, and the helmet size is optimized to fit the largest adult heads. The rigid helmet limits source-to-sensor distances to >3 cm which compromises the maximum achievable signal-to-noise ratio (SNR) and hence spatial resolution. Furthermore, due to their design, these SQUID-based MEG systems are costly and impractical for experiments in natural environments. Recent simulation studies have shown that on-scalp MEG can maximize SNR and achieve spatial resolution approaching 1 mm. Optically pumped magnetometers (OPMs) are a valid candidate for MEG sensors, as they operate above room temperature, and the sensor layout can be conformal to the scalp. The overall objective of this project is to develop a wearable, conformable, full-head coverage, 108- channel, OPM-based MEG system with unprecedented spatial resolution approaching 1 mm. The first Aim will develop the whole-cortex 108-channel OPM array along with the supporting systems (optical, electronic, software, etc.). The OPM MEG will be installed in a magnetically shielded room so that the array can be worn and move with the subject, enabling more naturalistic study paradigms. The second Aim will leverage the high- frequency spatial features available to the on-scalp OPMs to enhance the spatial resolution of the MEG system. Given unique subjects' head shapes, adaptive sampling of the magnetic topography (image) is essential to maximize the captured spatial frequency. Hence, information-theoretic analysis will be used to maximize the spatial resolution by optimizing the sensors locations. With the array being reconfigurable, rapid calibration techniques will be developed to determine the position of each OPM for each subject. To eliminate external magnetic noise and compensate for movement-induced distortion, physics-based models will be employed. The final Aim cross validates the performance metrics of the new OPM MEG system with a commercial SQUID system. By measuring retinotopy in the visual cortex, spatial localization between the MEG systems will be compared. By stimulating cerebellar activity, it will be studied if the conformal OPM array can better capture activity in this difficult-to-study region of the brain. Finally, by measuring resting-state MEG, intrinsic network connectivity in the human brain will be captured. This project will provide a whole-head OPM array that improves MEG measurements for people of all head sizes (from premature infants to the largest adults) and enable new experimental paradigms with a wearable array operating in semi-natural settings.

项目摘要/摘要 为了在人脑中多个尺度的神经元电路并研究脑动力学，那里 需要具有高时空分辨率在天然中运行的非侵入性功能性脑成像 环境。在非侵入性功能性脑成像方法中，磁脑电图（MEG）是 唯一可以将皮质活动映射到毫米空间分辨率的技术，以毫秒的时间分辨率 解决。当前的低温MEG系统采用超导量子干扰装置（squid） 磁力计。低温操作需要刚性和固定在头盔中的传感器阵列，然后 头盔尺寸被优化以适合最大的成年头。刚性头盔将源至传感器距离限制为> 3 CM损害了最大可实现的信噪比（SNR）以及因此空间分辨率。 此外，由于其设计，这些基于鱿鱼的MEG系统对于实验而言是昂贵和不切实际的 在自然环境中。最近的仿真研究表明，级别MEG可以最大化SNR和 实现接近1 mm的空间分辨率。光学抽气磁力计（OPM）是有效的候选者 对于MEG传感器，当它们在室温以上运行时，传感器布局可以与 头皮。该项目的总体目的是开发可穿戴，构想，全型覆盖范围，108- 频道，基于OPM的MEG系统，其空间分辨率接近1 mm。第一个目标 开发全皮层108通道OPM阵列以及支撑系统（光学，电子， 软件等）。 OPM MEG将安装在磁屏蔽的房间中，以便可以佩戴阵列 并与该主题相提并论，从而实现了更自然的研究范例。第二个目标将利用高级 频率空间特征可用于降低OPMS，以增强MEG的空间分辨率 系统。给定独特的受试者的头形，磁性地形的自适应采样（图像）为 对于最大化捕获的空间频率至关重要。因此，信息理论分析将用于 通过优化传感器位置来最大化空间分辨率。随着阵列可重新配置，快速 将开发校准技术来确定每个受试者的每个OPM的位置。消除 外部磁噪声并补偿运动引起的失真，基于物理的模型将是 雇用。最终目标交叉验证了新的OPM MEG系统的性能指标 商业鱿鱼系统。通过测量视觉皮层中的视网膜，MEG之间的空间定位 将比较系统。通过刺激小脑活性，如果可以使用保形OPM阵列可以进行研究 更好地捕获大脑难以研究区域的活动。最后，通过测量静止状态的梅格， 将捕获人脑中的内在网络连通性。该项目将提供全部OPM 改进了所有头大小的人的MEG测量的阵列（从早产儿到最大的人 成人），并启用具有在半天然设置中运行的可穿戴阵列的新实验范式。