记忆测验中故意答错行为的事件相关电位变化

Research on event-related potentials of dissimulation in memory test

目的 研究记忆测验中的故意答错行为的事件相关电位（ERP）变化.方法 用二项必选数字记忆测验程序编制ERP范式,20名在校学生在主动答对、故意答错和被动答错三种情况下完成试验任务.结果 ①三种试验条件下的反应时由短至长依次为：主动答对（681±21）ms、故意答错（741±25）ms和被动答错（946±31）ms,各组间差异具有显著性（F=115.73,P=0.000）.②所采集的ERP波形中,N2（160～200ms）和P2（200～300ms）成分在故意答错及被动答错条件下的波幅高于主动答对情况;其中N2成分的波幅在三种条件下差异有显著性（F=6.896,P＜0.01）,分别为：主动答对（-0.376±0.58）μV、故意答错（4.31±0.58）μV及被动答错（1.77±0.82）μV.结论 事件相关电位的某些指标对识别记忆测验中的故意答错行为有参考价值.

Objective To examine the dissimulation in memory test by event-related potentials （ERP）.Methods Recording the ERP of 20 students in the choosing tasks according to Binomial Forced-Choice Digit Memory Test （BFMDT） in three situations including reality,dissimulation and forced wrong choose. Results The reaction time was lengthened gradually by the situation of reality （ 681 ± 21 ） ms, dissimulation （ 741 ± 25 ） ms and forced wrong choose（ 946 ± 31 ） ms （F= 115.73, P = 0.000）. The main components in ERP waveforms, N2 （ 180 ～184 ms） and P2 （ 214 ～ 243 ms） had higher amplitudes in situations of dissimulation and forced wrong choose than that of reality. The amplitude of N2 showed significant difference in three groups（F=6. 896, P〈0.01 ）. The amplitudes were increased gradually by the situation with reality（ -0.376 ± 0.58 ）μV, dissimulation（ 0. 86 ± 0.71 ）μV and forced wrong choose（ 1.77 ±0.82）μV. Conclusion ERP may be an electrophysiological index of the intention of dissimulation in memory test.