任务提示的脑认知加工过程中神经振荡机制研究  

The Research of Neural Oscillation Mechanism During the Brain Cognitive Processing of Task Switching

作　　者：王宇 陈晨[1] 张家琦 彭丝雨 高军峰[1,2] WANG Yu;CHEN Chen;ZHANG Jia-qi;PENG Si-yu;GAO Jun-feng(School of Biomedical Engineering,South-Central University for Nationalities,Wuhan,Hubei 430074,China;School of Life Science and Technology,University of Electronic Science and Technology of China,Chengdu,Sichuan 610054,China)

机构地区：[1]中南民族大学生物医学工程学院认知科学国家民委重点实验室,湖北武汉430074 [2]电子科技大学生命科学与技术学院,四川成都610054

出　　处：《电子学报》2020年第5期960-965,共6页Acta Electronica Sinica

基　　金：国家自然科学基金(No.81271659,No.61773408);中央高校基础科研业务专项(No.CZZ19004,No.CZY19040);中国博士后科学基金(No.2014M552346)。

摘　　要：任务切换实验是评估人类认知灵活性的有效范式,其中提示语切换实验(Task Cuing)能够有效地测量任务切换的认知过程.为了深入研究任务切换的认知过程,本文设计了提示语(cue)和之后刺激(Target)比例为1∶8的提示语切换实验,采集了50名在校大学生的脑电.结合事件相关电位和事件相关谱扰动、序间相位相干、事件相关相位互相干等时频分析的方法研究了任务切换认知过程中的神经振荡机制.实验结果显示,在P200时间段里,腹侧前额叶与后顶叶之间神经振荡存在相位同步现象,并且后顶叶电极神经震荡的相角滞后于前额叶电极,这表明P200对应的检索过程是由前额叶驱动后顶叶的一种自上而下的控制过程.在P300的时间段里,对theta波段频谱分布的研究结果显示了切换任务中大脑的激活强度显著大于重复任务中大脑的激活强度,而且,两种任务中该频段的能量均主要分布在右侧后顶叶,它揭示了任务集配置和更新与theta波段神经振荡之间的密切关系.本文以上发现为揭示大脑认知灵活性的神经振荡机制提供了一种新的途径,有助于我们深入了解任务切换的认知加工过程.Task switch is an efficient experiment to evaluate human’s cognitive flexibility in which task cuing can effectively measure the cognitive process of task switching.In order to deeply study the cognitive process,we design the task cuing where the ratio of cue and target is 1∶8.The neural oscillation of task switching was studied by combining event related potentials(ERP)and time-frequency analysis including event-related spectral perturbation(ERSP),inter-trial phase coherence(ITPC),event-related phase cross coherence(ERPCOH)in this paper.For P200,the experiment result shows that the neural oscillation has phase synchronization between prefrontal cortex and posterior partial cortex and the phase angle of posterior partial cortex lags behind prefrontal cortex,indicating that the brain completed task rule retrieval and P200 reflects a top-down process driven by prefrontal cortex.For P300,the research results of theta band oscillation distribution show that the brain activation in the cue switch was significantly greater than in the cue repeat.Meanwhile,the power of theta band oscillation was mainly distributed in the posterior partial cortex,which shows that theta band oscillation is related with the reconfiguration and update of task set.The above findings provide a new way to reveal the neural oscillation mechanism of brain cognitive flexibility,which helps us to understand the cognitive process of task switching.

关 键 词：任务切换 提示语 认知灵活性 时频分析 神经振荡 

分 类 号：TP391.4[自动化与计算机技术—计算机应用技术] TP181[自动化与计算机技术—计算机科学与技术]