Hao Lei, Yang Junyi, Wang Yanqiu, Zhang Songyan, Xie Peng, Luo Qinghua, Ren Gaoping, Qiu Jiang
Key Laboratory of Cognition and Personality (SWU), Ministry of Education, Chongqing, PR China; School of Psychology, Southwest University, Chongqing 400715, PR China.
Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, PR China; Chongqing Key Laboratory of Neurobiology, Chongqing 400016, PR China; Institute of Neuroscience, Chongqing Medical University, Chongqing 400016, PR China.
Clin Neurophysiol. 2015 Jul;126(7):1331-7. doi: 10.1016/j.clinph.2014.10.146. Epub 2014 Oct 29.
The causal attribution of depressive patients in negative events was significantly important. However, few previous studies have explored its neural underpinnings.
The current study examines the neural basis of causal attribution in negative events of depressed patients (12) compared with healthy controls (12) by using the Attribution Style Task (AST). Briefly, participants were presented with 80 sentences describing 40 positive and 40 negative social events. Participants were asked to imagine the event happening to them and select the most likely cause with a button press: 1 self (internal), 2 another person, and 3 situation (external).
Behaviorally, controls showed a self-serving bias, whereas patients demonstrated a balanced attributional pattern with the attribution scores. Our fMRI results found a significant group difference in the inferior frontal gyrus and middle temporal gyrus in depressed participants compared to normal controls. Moreover, there was a significantly increased activation in the IPL during non-self-serving attributions in negative events of patients compared to controls. Most interestingly, we also found the BOLD signal change of the region of IPL was positively related to the duration of the illness of the patients.
Based on our findings, we may infer that a stronger activation of the IPL in depression may demonstrate that depressed patients always pay more attention to self-reference in negative events.
These interesting findings might provide a biomarker of subtle differences in brain signal alterations associated with depressive cognitive characteristics.
抑郁症患者对负面事件的因果归因具有显著重要性。然而,以往很少有研究探讨其神经基础。
本研究通过归因风格任务(AST),研究抑郁症患者(12名)与健康对照组(12名)在负面事件中因果归因的神经基础。简要来说,向参与者呈现80个描述40个积极和40个消极社会事件的句子。要求参与者想象事件发生在自己身上,并通过按按钮选择最可能的原因:1自我(内部),2另一个人,3情境(外部)。
在行为上,对照组表现出自我服务偏差,而患者在归因得分上表现出平衡的归因模式。我们的功能磁共振成像结果发现,与正常对照组相比,抑郁症患者的额下回和颞中回存在显著的组间差异。此外,与对照组相比,患者在负面事件的非自我服务归因过程中,顶下小叶的激活显著增加。最有趣的是,我们还发现顶下小叶区域的血氧水平依赖信号变化与患者的病程呈正相关。
基于我们的研究结果,我们可以推断,抑郁症中顶下小叶更强的激活可能表明抑郁症患者在负面事件中总是更关注自我参照。
这些有趣的发现可能为与抑郁认知特征相关的脑信号改变的细微差异提供一个生物标志物。