摘要
大脑疲劳的症状体现在认知能力的下降,认知功能主要由前额叶皮层(PFC)调控。功能性近红外脑成像技术(fNIRS)能够测量一段时间内的大脑血氧浓度变化,从而间接反映大脑皮层的激活程度。设计了一款具有10通道且可覆盖前额叶区域的可穿戴fNIRS头带,并使用该头带对受试者大脑进行检测,观察受试者是否进入疲劳状态。设备采用780 nm和850 nm的激光二极管和光电二极管作为光源和光电探测器,光源采用频分复用的调制方法来区分两种波长以及屏蔽环境光的干扰,并且采用时分复用的方法驱动光源以获得较高的探测效率。fNIRS头带制作完成后将其应用于间隔认知测试,结果发现氧合血红蛋白(HbO)和脱氧血红蛋白(Hb)的浓度均存在间隔性变化,证实了fNIRS头带的可行性。随后招募受试者参与模拟驾驶实验,并在模拟前后测量认知能力。fNIRS成像结果均能观察到在实验后期背外侧前额叶(DLPFC)皮层HbO浓度的下降,且认知任务结果显示认知能力下降,表明实验后期受试者大脑开始疲劳,由此验证了f NIRS头带检测疲劳的可行性。
The symptoms of brain fatigue are reflected in a decline in cognitive function,which is mainly regulated by the prefrontal cortex(PFC).Functional near-infrared spectroscopy(fNIRS)can measure the changes in cerebral blood oxygen concentration over a period of time,thereby indirectly reflecting the degree of activation of the cerebral cortex.Therefore,a wearable fNIRS headband with 10 channels that can cover the prefrontal area is designed,and the headband is used to detect the subject's brain to observe whether the subject enters the fatigue state.The headband uses 780 nm and 850 nm laser diodes and silicon photodiodes as light source and photodetector.The light source uses frequency division multiplexing modulation method to distinguish two different wavelengths and to shield the interference of ambient light,and also time division multiplexing to drive the light source to obtain higher detection efficiency.After the fNIRS headband was made,it was applied to the interval cognitive test.The results showed that there were interval changes in the concentration of oxygenated hemoglobin(HbO)and hemoglobin(Hb),which confirmed the feasibility of the fNIRS headband.Subjects were then recruited to participate in a simulated driving experiment,and cognitive ability was measured before and after the simulation.The results of fNIRS imaging showed a decrease in the concentration of HbO in the dorolateral prefrontal cortex(DLPFC)in the late stage of the experiment.Cognitive tasks showed a decline in cognitive ability,indicating that the subjects'brain began to fatigue in the late stage of the experiment,thus verifying the feasibility of fNIRS headband in detecting fatigue.
作者
沈无双
沈慧娟
苏彤
王浩
张学典
马佩
SHEN Wushuang;SHEN Huijuan;SU Tong;WANG Hao;ZHANG Xuedian;MA Pei(School of Optical-Electrical and Computer Engineering,University of Shanghai for Science and Technology,Shanghai 200093,China;Faculty of Psychology,Naval Medical University,Shanghai 200433,China)
出处
《光学仪器》
2024年第4期46-55,共10页
Optical Instruments
基金
国家重点研发计划(2017YFC0110200)
军民融合成果孵化专项(2022-RH19)
海军军医大学“深蓝”工程人才计划。
