轻度认知障碍患者早期面孔加工的事件相关电位研究

Early event-related potentials changes during early face processing of mild cognitive impairment patients by face-specific

目的研究轻度认知障碍患者面孔早期加工的事件相关电位特点。方法被试者分为正常老年对照组和轻度认知障碍组，各16名，均为右利手。刺激包括3种卡通面孔（中性、微笑、愤怒）和3种非面孔，要求被试者进行面孔识别任务，同时记录32导脑电图。结果1）无论MCI组还是正常组均产生了明显的颞－枕区分布的面孔特异性成分N170；2）MCI组N170潜伏期为[（158．91±2．17）ms]，长于正常对照组[（140．97±2．17）ms]，差异具有显著性（F=34．09，P〈0．01）；MCI组波幅为[（-4．42±0．28）μV]，低于正常对照组[（-7．00±0．28）μV]，差异具有显著性（F=41．52，P〈0．01）。结论MCI患者在面孔表情早期加工阶段即出现异常。

Objective To study early face processing of mild cognitive impairment patients by using ERP method. Methods Sixteen healthy old man（ normal group） and sixteen mild cognitive impairment patients （MCI group） served as subjects in experiment. Two runs of 300 stimuli（ duration ：50 ms） of 3 facial and 3 non-facial pictures were randomly presented with equal probability （ISI：from 1000 ms to 1500 ms randomly） , and the subjects were asked to react to facial stimuli and non-facial stimuli by pressing the left button and right button respectively as quickly as possible. Thirty-two channels electroencephalogram（EEG） was recorded by Neuroscan Nuamps System. Results 1 ） Specific-face component N170 was found in both groups, which was distributed at the temporal-occipital region. 2）Compared with N170 in normal group, N170 amplitude was significantly lower（ （ -4.42 ±0.28） μV vs （ - 7.00 ±0. 28 ） μV, F = 41.52, P 〈 0.01 ） at temporal-occipital region and delayed （ （ 158.91 ±2.17）ms vs （140.97 ±2.17）ms, F=34.09, P〈0.01） in mild cognitive impairment group. Conclusion The early face processing mechanism of mild cognitive impairment patients may be different from normal people.