Arch Gen Psych：揭示囤积症病人大脑决策制定的分子机制

近日，刊登在国际著名杂志Archives of General Psychiatry上的一篇研究报告中，研究者指出，患有囤积症（hoarding disorder，HD）的病人往往在大脑的某些区域中表现出异常的活动，而且当期处理属于或者不属于自己的事情的时候往往具有刺激依赖性。

囤积症被认为是过度的物体堆积症，而且患者没有能力去丢弃一些不用的东西，其病症在发展过程中表现为对决定的回避性。研究者David和其同事使用功能性磁共振成像技术（fMRI）测定了患者决定是否保留或者丢弃其财产时候的大脑神经活性。

本实验研究中共有107个研究对象，分别为HD患者31人，观念强迫性障碍患者（OCD）31人以及正常健康个体33人。研究中所使用的物体均为纸张文件，比如邮报或者报纸等。相比OCD和健康人这两组，研究者发现HD组患者在前扣带回皮质（ACC）和大脑岛叶上表现出异常的活性。当对不属于HD患者的文件作出处理时，其表此案出较低的大脑区域活性。然而，当决定要处理他们的文件时，HD患者大脑区域表现出过度的功能性磁共振成像信号。

当前发现的ACC和岛叶的异常和出现的HD模型一致，这就揭示了HD患者的决策过程可以促使病人很困难地处理自己的文件信息。

文章也揭示了HD患者更愿意去选择丢弃较少参加者的物品财产而不是另外两组患者的，最后作者总结道，HD患者的这种明显的两项模式，而不是针对参与者财产的ACC和岛叶活性功能亢进需要进一步深入研究。

编译自：Decision-Making Brain Activity in Patients With Hoarding Disorder

doi:10.1001/archgenpsychiatry.2011.1980
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Neural Mechanisms of Decision Making in Hoarding Disorder

David F. Tolin, PhD; Michael C. Stevens, PhD; Anna L. Villavicencio, PhD; Melissa M. Norberg, PhD; Vince D. Calhoun, PhD; Randy O. Frost, PhD; Gail Steketee, PhD; Scott L. Rauch, MD; Godfrey D. Pearlson, MD

Context Hoarding disorder (HD), previously considered a subtype of obsessive-compulsive disorder (OCD), has been proposed as a unique diagnostic entity in DSM-5. Current models of HD emphasize problems of decision-making, attachment to possessions, and poor insight, whereas previous neuroimaging studies have suggested abnormalities in frontal brain regions. Objective To examine the neural mechanisms of impaired decision making in HD in patients with well-defined primary HD compared with patients with OCD and healthy control subjects (HCs). Design We compared neural activity among patients with HD, patients with OCD, and HCs during decisions to keep or discard personal possessions and control possessions from November 9, 2006, to August 13, 2010. Setting Private, not-for-profit hospital. Participants A total of 107 adults (43 with HD, 31 with OCD, and 33 HCs). Main Outcome Measures Neural activity as measured by functional magnetic resonance imaging in which actual real-time and binding decisions had to be made about whether to keep or discard possessions. Results Compared with participants with OCD and HC, participants with HD exhibited abnormal activity in the anterior cingulate cortex and insula that was stimulus dependent. Specifically, when deciding about items that did not belong to them, patients with HD showed relatively lower activity in these brain regions. However, when deciding about items that belonged to them, these regions showed excessive functional magnetic resonance imaging signals compared with the other 2 groups. These differences in neural function correlated significantly with hoarding severity and self-ratings of indecisiveness and “not just right” feelings among patients with HD and were unattributable to OCD or depressive symptoms. Conclusions Findings suggest a biphasic abnormality in anterior cingulate cortex and insula function in patients with HD related to problems in identifying the emotional significance of a stimulus, generating appropriate emotional response, or regulating affective state during decision making.