高密度近红外光谱成像及其应用于视觉非随意注意研究

Divided visual attention,which is closely realted with social activities and diseases in driver fatigue, hyperactivity, ageing, and sleep, becames one of hot topics in both fields of neuroscience and medicine. Divided visual attention was studied mostly by electroencephalogram; the hemodynamic response in related brain area is unclear. We proposed to study cerebral hemodynamic response to divided visual attention in relative brain areas prefrontal and occipital areas with functional near-infrared spectroscopy (fNIRS).The emerging high density fNIRS provided a solution idea to the problems of fNIRS, including relative measurements and low spatial resolution. However its crucial portion, probe design, necessitates further exploration and currently it is limited to monitoring single brain area of infants. This project will quantitatively optimaze the probe desgins for multiple brain areas based on fully researching light transport properties in adult brain, develop an improved high density fNIRS capable of simulatneous measurements in prefrontal and occipital lobes, and then apply it to research divided visual attention at different attention level (sober or tired). Our research will provide a novel way and portable instrument for the divided visual attention research; the hemodynamic response characteristics to divided visual attention at different level will potentially be used as novel and effective eveidences and indictors in monitoring fatigue in driving or working, and accordingly promote the widespread usage of fNIRS in traffic safety and medicine.

视觉非随意注意是神经科学的热点课题，与疲劳驾驶，多动症，衰老，睡眠等社会活动和精神疾病关系密切。它的研究主要采用脑电方法，其相关脑区的血液动力学响应还不清楚。本项目将采用功能近红外光谱术（fNIRS）研究视觉非随意注意主要参与脑区额叶和枕叶的血液动力学变化。新出现的高密度fNIRS为fNIRS存在的非绝对量测量、空间分辨率低等问题带来了解决方向，但其中关键的探头设计还处于探索阶段，目前仅用于婴幼的单一脑区检测。本项目拟通过研究光在不同脑区的传输特性，定量优化不同脑区的高密度探头设计，实现可同步检测成人额叶和枕叶的高密度 fNIRS，研究清醒及不同驾驶疲劳水平下视觉非随机注意的额叶和枕叶血液动力学变化。本研究可为视觉非随意注意提供新的研究思路和测量仪器；不同疲劳水平下视觉非随意注意的血液动力学变化特征将有望为疲劳驾驶/作业的监测提供新依据/指标，促进fNIRS在交通安全和医学中的应用。

视觉非随意注意是神经科学的热点课题，与疲劳驾驶，多动症，衰老，睡眠等社会活动和精神疾病关系密切。它的研究主要采用脑电方法，其相关脑区的血液动力学响应还不清楚。本项目将采用功能近红外光谱术（fNIRS）研究视觉非随意注意主要参与脑区额叶和枕叶的血液动力学变化。新出现的高密度fNIRS为fNIRS存在的非绝对量测量、空间分辨率低等问题带来了解决方向，但其中关键的探头设计还处于探索阶段，目前仅用于婴幼的单一脑区检测。本项通过研究光在不同脑区的传输特性，定量优化不同脑区的高密度探头设计，实现了同步检测成人额叶和枕叶的高密度 fNIRS，研究了清醒及不同驾驶疲劳水平下视觉非随机注意的额叶和枕叶血液动力学变化。研究发现随着驾驶时间的增加，司机的含氧血红蛋白浓度有先上升后平稳再上升的情况，与此同时视觉非随意注意的实验结果也有同样的变化趋势，除此之外在前额叶左脑部分区域脱氧血红蛋白和疲劳程度呈强相关的关系（R=0.816）。所以我们认为在前额叶左侧部分敏感点的血液参数（含氧血红蛋白）何以作为衡量驾驶疲劳水平的一个指标。该参量将有望为疲劳驾驶/作业的监测提供新依据/指标，促进fNIRS在交通安全和医学中的应用。