基于脑电的精神疲劳对工作记忆信息传输与整合影响的研究

Mental fatigue has become a ubiquitous yet easily overlooked health problem which can impair people's cognitive and behavioral abilities. However, the mechanism of cognitive impairment caused by mental fatigue is not yet clear. Working memory is described as a human cognitive center, which could restrict the ability of information processing. In this project, mental fatigue is induced by adaptive N-back working memory task. The EEG data are recorded. The single rhythm EEG based complex networks are further established and analyzed to investigate the effect of mental fatigue on the transmission efficiency of the working memory information flow and the connectivity of the brain regions. The phase synchronization of single rhythm EEG is analyzed to investigate the effect of mental fatigue on the integration of working memory information and the cooperation of brain regions EEG frequency cross coupling is analyzed to investigate the effect of mental fatigue on the coding of working memory information and information communication in different brain regions. The event related potential induced by working memory task is analyzed to investigate the effect of mental fatigue on the allocation of cognitive resources of working memory. To explore the influence of mental fatigue on the transmission and integration of working memory information, the correlation and dynamic association characteristics of the features extracted from the studies mentioned above are investigated. The aim of this project is to explore the neural mechanism of cognitive impairment caused by mental fatigue from the perspective of the transmission and integration of working memory information, and to provide more theoretical and experimental evidences for improving mental fatigue using nervous regulation.

精神疲劳已经成为一种普遍又极易被忽视的健康问题，会损害人的认知和行为能力。但精神疲劳损害认知功能的神经机制尚不明确。工作记忆被称为人类认知中枢，是限制信息处理能力的瓶颈。本项目拟采用自适应N-back工作记忆实验范式诱发精神疲劳同时记录脑电数据;构建单节律脑电复杂网络，研究精神疲劳对工作记忆信息流的传递效率与脑区连接性影响；分析单节律脑电相位同步性，研究精神疲劳对工作记忆信息整合与脑区协调工作的影响；分析频率间脑电信息耦合，研究精神疲劳对工作记忆信息编码与跨脑区信息通讯的影响；利用工作记忆诱发事件相关电位，研究精神疲劳对工作记忆认知资源分配影响；分析上述研究提取的各特征相关性和动态关联特性，研究精神疲劳对工作记忆信息传输与整合的动态影响；以期从工作记忆信息传输与整合的角度，更深入地探索精神疲劳损害认知功能的神经机制，为神经调控改善精神疲劳提供更多理论和实验依据，具有重要研究意义和应用前景。

精神疲劳是指人体现出的精神警觉性和心理表现下降的一种状态，会引起瞬间的注意力分散、反应迟缓或协调性不够，高风险作业等行业中可能会导致极为严重的事故。长期过度的精神疲劳会导致神经衰弱、失眠、抑郁、慢性疲劳综合症等。精神疲劳已经成为影响人类的一大健康问题。工作记忆是人类的认知中枢和基础。工作记忆能力受损会恶化认知功能表现。精神疲劳对工作记忆的影响目前还有待进一步的研究。因此本项目以自适应N-back工作记忆实验范式诱发精神疲劳，采用Sternberg和N-back两种工作记忆范式实验，记录大学生志愿者在精神疲劳前后的脑电信号和行为学指标，对不同状态下脑电信号的脑网络、同步性、频率交叉耦合、动态连接等特征进行了求取和对比统计分析，提取了工作记忆任务下不同时期的事件相关电位并对其特征进行了对比分析，研究了精神疲劳对不同频率的大脑电信号在工作记忆过程中的协同工作以及工作记忆过程信息的跨脑区交流与整合的影响。结果表明，精神疲劳会导致工作记忆表现变差，影响脑网络的连接性，降低信息传输效率，改变节律的同步性，提高网络拓扑属性变异性，对频率间信息的耦合也有一定影响。本项目能够从神经信息传输的角度，更深入地探索精神疲劳损害认知功能的神经机制，为神经调控改善精神疲劳提供更多理论和实验依据。