Department of Neuroscience Program, Washington University, St. Louis, Missouri 631320, USA.
Biol Psychiatry. 2010 May 15;67(10):902-11. doi: 10.1016/j.biopsych.2009.10.020. Epub 2009 Dec 9.
Emotional impairments such as anhedonia are often considered key features of schizophrenia. However, self-report research suggests that emotional experience in response to affect-eliciting stimuli is intact in schizophrenia. Investigation of neural activity during emotional experience may help clarify whether symptoms of anhedonia more likely reflect alterations of in-the-moment hedonic experience or impairments in other aspects of goal-directed behavior.
Forty individuals with DSM-IV-TR schizophrenia or schizoaffective disorder and 32 healthy control subjects underwent functional magnetic resonance imaging while making valence and arousal ratings in response to emotional pictures, words, and faces. Blood oxygen level-dependent responses were compared between patients and control subjects and were correlated with questionnaire measures of anhedonia.
Patients showed some evidence of blunted valence but not arousal ratings in response to emotional stimuli compared with control subjects. Higher anhedonia scores were associated with blunted valence ratings in both groups and fully mediated the group differences in valence ratings. Functional activity was largely intact in patients, except for regions in right ventral striatum and left putamen, which showed reduced responses to positive stimuli. Higher anhedonia was associated with reduced activation to positive versus negative stimuli in bilateral amygdala and right ventral striatum in patients and in bilateral caudate in control subjects.
Increased anhedonia is associated with a reduced experience of valence in both patients and control subjects, and group differences in experienced valence are likely driven by individual differences in anhedonia. Reduced activation of the striatum and amygdala may contribute to symptoms of anhedonia by failing to signal the salience of positive events.
快感缺失等情绪障碍通常被认为是精神分裂症的主要特征。然而，自我报告研究表明，精神分裂症患者对情绪刺激的情绪体验是完整的。对情绪体验过程中的神经活动进行研究，可能有助于阐明快感缺失症状是否更可能反映即时愉悦体验的改变，还是反映其他目标导向行为方面的障碍。
40 名符合 DSM-IV-TR 精神分裂症或分裂情感障碍诊断标准的患者和 32 名健康对照者在观看情绪图片、词语和面孔时进行功能磁共振成像，并对其进行效价和唤醒度评定。比较患者和对照组之间的血氧水平依赖反应，并与快感缺失问卷测量结果进行相关分析。
与对照组相比，患者对情绪刺激的效价评定显示出一定程度的迟钝，但对唤醒度评定没有明显差异。两组患者的快感缺失评分均与效价评定迟钝呈正相关，且完全介导了两组间的效价评定差异。除右侧腹侧纹状体和左侧壳核对正性刺激的反应性降低外，患者的功能活动基本正常。患者双侧杏仁核和右侧腹侧纹状体对正性刺激与负性刺激的激活差异与快感缺失评分相关，而对照组双侧尾状核对正性刺激与负性刺激的激活差异与快感缺失评分相关。
快感缺失程度增加与患者和对照组效价体验的降低有关，且组间效价体验的差异可能是由快感缺失的个体差异驱动的。纹状体和杏仁核的激活减少可能通过未能对正性事件的重要性发出信号，导致快感缺失症状。
