冲突性负波N270对抑郁症患者认知功能损害的评价

Cognitive impairment in patients with major depressive disorder revealed by event-related potential N270

目的：揭示抑郁症患者的认知功能损害,探讨在该病患者中冲突性负波N270的变化及意义。方法：顺序出现的颜色相同或不同的刺激对随机呈现。25名抑郁症患者和25名年龄、性别匹配的正常对照并判断每对刺激的颜色是否相同并相应按键反应,同时在头皮记录事件相关电位。结果：在患者组和对照组,颜色不同的刺激对均可诱发出N270。患者组N270的潜伏期延长(P_3、P_4,P＜0．05),且缺失率高于对照组(F_3,5/25；F_4,4/25),各部位N270的峰波幅显著低于对照组。结论：抑郁症患者存在认知功能损害,N270可作为评价该病认知功能障碍的一个指标。

Objective：To study the cognitive impairments of patients with major depression （MD） and to verify the feasibility of N270 as a clinical examination method to evaluate the cognitive state of MD patients. Methods： Stimulus pairs with identical （match condition） or different （conflict condition） colors were randomly presented to subjects. Twenty-five MD patients and twenty-five age-matched control subjects determined if the two stimuli in a pair had the same color while ERPs were recorded from their scalps. Results：N270 was evoked hy the S2 of the conflict condition in either controls or patients. N270 disappeared in more patients than in control subjects and the patient group exhibited a more delayed and smaller N270 than the control group. Conclusions： MD patients show cognitive deficits. N270 is an effective index to detect the cognitive impairment in MD patients.