抑郁症患者识别情绪词的事件相关电位实验研究

The effects of recognition of emotional words on ERPs of patients with major depression

目的 探讨抑郁症患者识别汉语情绪词所诱发的事件相关电位 (ERPs)特点。方法 采用神经扫描仪记录 16名抑郁症患者和 18名正常对照组视觉识别汉语情绪词诱发的ERPs。采用汉语情绪词选择作业实验刺激模式 ,其中正、负性词各占 2 0 % ,中性词占 60 % ,要求对正、负性词作出选择。结果 ( 1)抑郁症组大部分ERP成分波幅呈下降趋势 (P <0 .0 5 ) ,但N2 5 0波幅高于正常对照组 ,尤其是FZ、F4点 (P <0 .0 5 )。两组潜伏期差异无显著性意义 (P >0 .0 5 )。 ( 2 )抑郁症颅脑电位分布范围比正常对照组小 ,其中正性、负性词N65 0以右前额区分布明显。 ( 3 )重复测量三因素方差分析结果发现 ,不同情绪词、电极记录点、组间因素对情绪词ERPs各成分的波幅和潜伏期有显著的主效应与交互效应。结论 抑郁症患者识别情绪词所诱发的事件相关电位表现异常。

Objective To investigate the effects of recognition of emotional content words on event-related potentials (ERPs) of patients with major depression. Methods ERPs were recorded in 16 patients with major depression and 18 healthy subjects while they performed a visual Chinese emotional content words recognition task. The study used a word identification task consisting of 20% negative and 20% positive words as well as 60% neutral words. Results The ERPs demonstrated similar waveform (N90,P160,N250,P290,N350,P490,N650) between depression patients and normal group, but its components were different. Amplitudes of many ERPs components in patients group were significantly decreased but N250 were significantly increased in FZ and F4 as compared with those of the normal groups (P<0.05). Scalp topography had the same landscape in the two groups but was smaller in patient groups, and N650 to positive and negative words had larger amplitude over the right-prefrontal regions. As revealed by repeated measures ANOVA, significant effect was caused by emotional content words, electrode codes and subjects factors on amplitude and latency of ERPs. Conclusion The findings provided electrophysiological evidence that cognitive dysfunction of prefrontal cerebral cortex existed in patients with major depression.