Whalley Matthew G, Rugg Michael D, Smith Adam P R, Dolan Raymond J, Brewin Chris R
Sub-Department of Clinical Health Psychology, University College London, Gower Street, London WC1E 6BT, UK.
Brain Cogn. 2009 Feb;69(1):98-107. doi: 10.1016/j.bandc.2008.05.008. Epub 2008 Jul 9.
In the present study, we used fMRI to assess patients suffering from post-traumatic stress disorder (PTSD) or depression, and trauma-exposed controls, during an episodic memory retrieval task that included non-trauma-related emotional information. In the study phase of the task neutral pictures were presented in emotional or neutral contexts. Participants were scanned during the test phase, when they were presented with old and new neutral images in a yes/no recognition memory task. fMRI results for the contrast between old and new items revealed activation in a predominantly left-sided network of cortical regions including the left middle temporal, bilateral posterior cingulate, and left prefrontal cortices. Activity common to all three groups when correctly judging pictures encoded in emotional contexts was much more limited. Relative to the control and depressed groups the PTSD group exhibited greater sensitivity to correctly recognised stimuli in the left amygdala/ventral striatum and right occipital cortex, and more specific sensitivity to items encoded in emotional contexts in the right precuneus, left superior frontal gyrus, and bilateral insula. These results are consistent with a substantially intact neural system supporting episodic retrieval in patients suffering from PTSD. Moreover, there was little indication that PTSD is associated with a marked change in the way negatively valenced information, not of personal significance, is processed.
在本研究中,我们使用功能磁共振成像(fMRI)对创伤后应激障碍(PTSD)患者、抑郁症患者以及经历过创伤的对照组进行评估,评估过程采用一项情景记忆检索任务,其中包含与创伤无关的情感信息。在任务的研究阶段,中性图片在情感或中性背景下呈现。在测试阶段对参与者进行扫描,此时他们在一个是/否识别记忆任务中会看到旧的和新的中性图像。旧项目与新项目对比的fMRI结果显示,主要在左侧的皮质区域网络出现激活,包括左颞中回、双侧后扣带回和左前额叶皮质。当正确判断在情感背景下编码的图片时,三组共有的活动则更为有限。相对于对照组和抑郁症组,PTSD组在左杏仁核/腹侧纹状体和右枕叶皮质对正确识别的刺激表现出更高的敏感性,在右楔前叶、左额上回和双侧脑岛对在情感背景下编码的项目表现出更具特异性的敏感性。这些结果与PTSD患者中支持情景检索的神经系统基本完整是一致的。此外,几乎没有迹象表明PTSD与处理无个人意义的负性价信息的方式有显著变化有关。