“延迟匹配样本任务”范式下人误的ERP研究

ERP study on the human error in delayed matching-to-sample task paradigm

人因失误可分为虚报(执行差错)和漏报(忽略)两大类。为了探讨人因失误的机理,提高人因认知的可靠性,采用事件相关电位技术(Even-t Related Brain Potentials,ERP)和延迟匹配样本任务范式,研究两类失误在认知加工不同阶段(信息编码输入、信息复述保持和信息提取匹配)的事件相关电位差异。试验刺激的编排、呈现及反应时(Reaction Time,RT)数据的采集通过E-Prime编程软件实现,认知加工3个阶段的脑电信号利用德国BP公司64导脑电记录系统采集。数据方差分析结果表明,漏报的反应时大于虚报的反应时(p<0.05),验证了内隐记忆的存在。ERP总平均图及P300平均峰值配对t检验表明,两类失误的脑电差异主要表现在信息编码输入阶段,具体表现为Pz电极点漏报的P300波幅显著大于虚报的P300波幅(p<0.01);信息复述保持阶段和信息提取匹配阶段脑电差异不显著,原因在于P300的注意效应。研究表明,P300波幅可作为反映虚报与漏报不同加工机制的脑电指标,信息编码阶段对信息的加工程度可能是导致不同类型人误的主要原因。

Human error can be divided into two categories known as the ＇false alarm＇ and ＇miss＇,which can hardly be described as the gap of the brain＇s event-related potentials（ERP） in different cognitive processing stages.Aimed at exploring the mechanism of human error and improve human cognitive reliability,we have been trying to use the technical term of event-related brain potentials（ERP） and ＇delayed matching-to-sample task＇ paradigm to analyze the ERP difference between ＇false alarm＇ and ＇miss＇ in different cognitive processing stages（information coding-encoding,information input,storing,matching and extracting）.For our research purpose,we have chosen our experimental stimuli from twenty six English letters.The sample letters we have chosen were composed of eight capitalized letters which are not repeated when arranged in a square with the target letter being in lowercase.In the experiment,the E-Prime program was used to arrange and present the experimental stimuli and then collect the data of reaction time,and a German BP Company-made 64-channels electroencephalogram（EEG） recording system was used to collect the EEG signal in three different stages of ＇delayed matching-to-sample task＇.The data of reaction time（RT） and electroencephalogram produced by five subjects were handled with analysis of variance（ANOVA） and paired t-test of average peak of P300 in Pz,Cz and Fz（electrode points） respectively.The results of analysis of variance（ANOVA） showed that the reaction time mean of ＇miss＇ was larger than ＇false alarm＇（p0.05）,which is much likely to imply there exists the implicit memory.The grand-average ERP and the paired t-test results of the average peak of P300 can probably indicate that the ERP difference between the above said two kinds of human error tends to appear in the information encoding stage,which are embodied in P300 amplitude of ＇miss＇ being significantly greater than ＇false alarm＇ in Pz electrode point（p0.01）.ERP of the information keeping stage and information matching stage may have no much difference,which may come about due to the attention effect of P300.The experiment results of ours reveal that P300 amplitude could be an index of EEG reflecting the different processing mechanism between the ＇false alarm＇ and the ＇miss＇,and the degree of information processing in coding stage might be the main reason accounting for the different human-sense error.