Salience and central executive networks track overgeneralization of conditioned-fear in post-traumatic stress disorder.
Salience and central executive networks track overgeneralization of conditioned-fear in post-traumatic stress disorder.
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DOI：
10.1017/s0033291720001166
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发表时间：
2021-11
影响因子：
6.9
通讯作者：
Lissek, Shmuel M.
中科院分区：
文献类型：
--
作者：
Berg, Hannah;Ma, Yizhou;Rueter, Amanda;Kaczkurkin, Antonia;Burton, Philip C.;DeYoung, Colin G.;MacDonald, Angus W., III;Sponheim, Scott R.;Lissek, Shmuel M.
关键词：
条件性恐惧的泛化是创伤后应激障碍（PTSD）的一个核心特征，是近年来神经影像学研究的热点。这些研究的一个显著结果是，泛化的神经相关性落入包括显著性（SN）、中央执行（CEN）和默认网络（DN）在内的成熟功能网络的中枢的频率。因此，迄今为止发现的泛化神经基质可能反映了大规模大脑网络的痕迹，这些网络形成了泛化的更广泛的神经表征。本研究首次基于网络分析了其中的泛化和创伤后应激障碍相关异常。在具有广泛PTSD症状严重程度的男性退伍军人（N = 58）中，在广义条件性恐惧任务期间评估了代表SN、CEN和DN的已建立内在连接网络（ICN）中的fMRI反应。这个任务包括五个大小不同的戒指。极端的大小作为条件化的刺激（CS+：与电击配对）和安全性的线索（CS-），和三个中间的大小作为泛化刺激（GS）形成一个连续的大小之间的CS+和CS-。泛化梯度被评估为从CS+，通过GS，到CS-的行为和ICN反应斜率。增加创伤后应激障碍的发病率预计与较低的斜率有关，表明较强的泛化能力。SN、CEN和DN反应沿着泛化梯度下降，SN和CEN内和之间的泛化水平与PTSD症状严重程度成比例。广义条件性恐惧的神经基础包括依附于大脑功能组织的大规模网络。目前的研究结果暗示SN和CEN的泛化水平是PTSD有希望的神经标志物。
Generalization of conditioned-fear, a core feature of post-traumatic stress disorder (PTSD), has been the focus of several recent neuroimaging studies. A striking outcome of these studies is the frequency with which neural correlates of generalization fall within hubs of well-established functional networks including salience (SN), central executive (CEN), and default networks (DN). Neural substrates of generalization found to date may thus reflect traces of large-scale brain networks that form more expansive neural representations of generalization. The present study includes the first network-based analysis of generalization and PTSD-related abnormalities therein. fMRI responses in established intrinsic connectivity networks (ICNs) representing SN, CEN, and DN were assessed during a generalized conditioned-fear task in male combat veterans (N = 58) with wide-ranging PTSD symptom severity. The task included five rings of graded size. Extreme sizes served as conditioned danger-cues (CS+: paired with shock) and safety-cues (CS−), and the three intermediate sizes served as generalization stimuli (GSs) forming a continuum-of-size between CS+ and CS−. Generalization-gradients were assessed as behavioral and ICN response slopes from CS+, through GSs, to CS−. Increasing PTSD symptomatology was predicted to relate to less-steep slopes indicative of stronger generalization. SN, CEN, and DN responses fell along generalization-gradients with levels of generalization within and between SN and CEN scaling with PTSD symptom severity. Neural substrates of generalized conditioned-fear include large-scale networks that adhere to the functional organization of the brain. Current findings implicate levels of generalization in SN and CEN as promising neural markers of PTSD.