目的 探讨抑郁症患者由表情刺激所诱发的视觉P300的变化。方法 对30例抑郁症患者（抑郁症组）和30名正常对照者（正常对照组）进行自编社会人口学资料表及汉密尔顿抑郁量表(HAMD)评估，对两组进行由悲伤、高兴、惊讶、生气和厌恶五种表情刺激所诱发的视觉P300指标的检测和比较，对抑郁症组HAMD评分与视觉P300指标进行相关性分析。结果 抑郁症组悲伤表情诱发的靶P3潜伏期为（447.23±26.90）ms，高兴表情诱发的靶P3潜伏期为（444.40±28.52）ms，均较正常对照组显著延长（P<0.05）。抑郁症组HAMD评分与五种表情诱发的P300各指标之间无相关性（P＞0.05）。结论 抑郁症患者具有异常的由表情刺激诱发的视觉P300指标变化。

Objective To investigate the changes of visual P300 evoked by facial expression stimulus in patients with depression. Methods Thirty patients with depression (depression group) and 30 normal controls (control group) were enrolled, and were evaluated by self-designed demographic questionnaire and Hamilton depression scale (HAMD). Besides, the examinations of visual P300 evoked by five facial expression stimulus, including depression, happiness, surprise, anger and disgust were conducted, and were compared between two groups. The correlation analysis of HAMD score with visual P300 was performed in depression group. Results The target P3 latency evoked by depression facial expression was (447.23±26.90) ms, that evoked by happiness facial expression was (444.40±28.52) ms, and both were significantly longer than those of control group (P<0.05). The HAMD score was not correlated with visual P300 evoked by facial expression stimulus in depression group (P＞0.05). Conclusion There are abnormal changes of visual P300 evoked by facial expression stimulus in patients with depression.