This work describes the design and development of a four-channel near-infrared spectroscopy system to detect the oxygenated and deoxygenated hemoglobin concentration changes in the brain during various motor tasks. The system uses light-emitting diodes corresponding to two wavelengths of 760 nm and 850 nm sensitive to deoxygenated and oxygenated hemoglobin concentration changes, respectively. The response is detected using a photodetector with an integrated transimpedance amplifier. The system is designed with four channels for functional near-infrared spectroscopy (fNIRS) signals acquisition. Two experiments were conducted to demonstrate the ability of the system to detect the changes in hemodynamic responses of different tasks. In the first experiment, the hemodynamic changes during motor execution and imagery of right- and left-fist clenching tasks were acquired by the developed system and validated against a standard multichannel NIRS system. In another experiment, the fNIRS signals during rest and motor execution of right-fist clenching task were acquired using the system and classified. The results demonstrate the ability of the designed system to detect the brain hemodynamic changes during various tasks. Also, the activation patterns obtained by the developed system with a minimum number of channels are on par with those obtained by the commercial system. The developed four-channel NIRS system is user-friendly and has been designed with inexpensive components, unlike the commercially available NIRS instruments that are cumbersome and expensive.

中文翻译：

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用于测量脑血流动力学反应的可穿戴四通道近红外光谱系统的设计

这项工作描述了四通道近红外光谱系统的设计和开发，该系统可检测各种运动任务期间大脑中氧化和脱氧血红蛋白浓度的变化。该系统使用分别对应于对脱氧和氧合血红蛋白浓度变化敏感的两个波长760 nm和850 nm的发光二极管。使用带有集成跨阻放大器的光电检测器检测响应。该系统设计有四个通道，用于功能近红外光谱（fNIRS）信号采集。进行了两个实验，以证明该系统检测不同任务的血液动力学反应变化的能力。在第一个实验中 通过开发的系统获取运动执行过程中的血流动力学变化以及左右手紧握任务的图像，并通过标准的多通道NIRS系统对其进行验证。在另一个实验中，右手紧握任务的休息和运动执行过程中的fNIRS信号已使用该系统获取并进行了分类。结果表明，所设计的系统具有检测各种任务期间脑血流动力学变化的能力。而且，由开发的系统以最少数量的通道获得的激活模式与由商业系统获得的激活模式相同。与市售的NIRS仪器笨重且昂贵的情况不同，开发的四通道NIRS系统操作简便，并且使用廉价的组件进行设计。