BabyMEG: A whole-head pediatric magnetoencephalography system for human brain development research
BabyMEG: A whole-head pediatric magnetoencephalography system for human brain development research
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DOI：
10.1063/1.4962020
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发表时间：
2016-09-01
影响因子：
1.6
通讯作者：
Paulson, Douglas
中科院分区：
文献类型：
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作者：
Okada, Yoshio;Hamalainen, Matti;Paulson, Douglas
我们开发了一个375通道，全头脑磁图（MEG）系统（“BabyMEG”），用于研究生命最初几年期间人类大脑的电生理发育。在美国，头盔可以容纳95%的36个月大的男孩。独特的双层传感器阵列包括：（1）内层的270个磁力计（直径10 mm，类似于15 mm线圈间距），（2）外层距离内层4 cm的35个三轴磁力计（20 mm x 20 mm）。此外，还有三个三轴参考磁力计。借助一个远程操作的位置调节机构，传感器阵列可以被定位，以提供一个均匀的短间距（平均8.5毫米）之间的传感器阵列和杜瓦瓶的室温表面。传感器连接到超导量子干涉装置（SQUID）在4.2 K下工作，内部传感器的灵敏度中值为7.5 fT/根Hz，外层传感器的灵敏度中值为4 fT/根Hz。SQUID输出由24位采集系统数字化。闭合循环氦气再循环器提供免维护连续运行，无需氦气，在MEG测量期间无需中断。自2015年3月起，带回收机的BabyMEG已全面投入使用。正在进行的自发脑活动可以在真实的时间内进行监测，而不会受到包括再循环器在内的外部磁噪声源的干扰，使用轻度屏蔽的双层磁屏蔽室、外部主动屏蔽、信号空间投影方法和合成梯度计方法的组合。皮层中的诱发反应可以清楚地检测到，而无需平均。这些新的设计特征和功能代表了MEG的几个进步，增加了该技术在基础神经科学以及临床研究和患者研究中的实用性。出版社：AIP Publishing
We developed a 375-channel, whole-head magnetoencephalography (MEG) system ("BabyMEG") for studying the electrophysiological development of human brain during the first years of life. The helmet accommodates heads up to 95% of 36-month old boys in the USA. The unique two-layer sensor array consists of: (1) 270 magnetometers (10 mm diameter, similar to 15 mm coil-to-coil spacing) in the inner layer, (2) thirty-five three-axis magnetometers (20 mm x 20 mm) in the outer layer 4 cm away from the inner layer. Additionally, there are three three-axis reference magnetometers. With the help of a remotely operated position adjustment mechanism, the sensor array can be positioned to provide a uniform short spacing (mean 8.5 mm) between the sensor array and room temperature surface of the dewar. The sensors are connected to superconducting quantum interference devices (SQUIDs) operating at 4.2 K with median sensitivity levels of 7.5 fT/root Hz for the inner and 4 fT/root Hz for the outer layer sensors. SQUID outputs are digitized by a 24-bit acquisition system. A closed-cycle helium recycler provides maintenance-free continuous operation, eliminating the need for helium, with no interruption needed during MEG measurements. BabyMEG with the recycler has been fully operational from March, 2015. Ongoing spontaneous brain activity can be monitored in real time without interference from external magnetic noise sources including the recycler, using a combination of a lightly shielded two-layer magnetically shielded room, an external active shielding, a signal-space projection method, and a synthetic gradiometer approach. Evoked responses in the cortex can be clearly detected without averaging. These new design features and capabilities represent several advances in MEG, increasing the utility of this technique in basic neuroscience as well as in clinical research and patient studies. Published by AIP Publishing.