Department of Neuroscience, Western University, London, Ontario, Canada.
Department of Psychiatry, Western University, London, Ontario, Canada.
Hum Brain Mapp. 2018 Nov;39(11):4258-4275. doi: 10.1002/hbm.24244. Epub 2018 Jul 13.
Posttraumatic stress disorder (PTSD) has been associated with a disturbance in neural intrinsic connectivity networks (ICN), including the central executive network (CEN), default mode network (DMN), and salience network (SN). Here, we conducted a preliminary investigation examining potential changes in ICN recruitment as a function of real-time fMRI neurofeedback (rt-fMRI-NFB) during symptom provocation where we targeted the downregulation of neural response within the amygdala-a key region-of-interest in PTSD neuropathophysiology. Patients with PTSD (n = 14) completed three sessions of rt-fMRI-NFB with the following conditions: (a) regulate: decrease activation in the amygdala while processing personalized trauma words; (b) view: process trauma words while not attempting to regulate the amygdala; and (c) neutral: process neutral words. We found that recruitment of the left CEN increased over neurofeedback runs during the regulate condition, a finding supported by increased dlPFC activation during the regulate as compared to the view condition. In contrast, DMN task-negative recruitment was stable during neurofeedback runs, albeit was the highest during view conditions and increased (normalized) during rest periods. Critically, SN recruitment was high for both the regulate and the view conditions, a finding potentially indicative of CEN modality switching, adaptive learning, and increasing threat/defense processing in PTSD. In conclusion, this study provides provocative, preliminary evidence that downregulation of the amygdala using rt-fMRI-NFB in PTSD is associated with dynamic changes in ICN, an effect similar to those observed using EEG modalities of neurofeedback.
创伤后应激障碍(PTSD)与神经固有连接网络(ICN)的紊乱有关,包括中央执行网络(CEN)、默认模式网络(DMN)和突显网络(SN)。在这里,我们进行了一项初步研究,考察了在症状激发期间,作为目标的杏仁核下调神经反应的功能磁共振成像实时神经反馈(rt-fMRI-NFB)的功能,以检查 ICN 募集的潜在变化,杏仁核是 PTSD 神经病理学的关键重点区域。14 名 PTSD 患者完成了三次 rt-fMRI-NFB 疗程,条件如下:(a)调节:在处理个性化创伤词时降低杏仁核的激活;(b)观察:在不试图调节杏仁核的情况下处理创伤词;(c)中性:处理中性词。我们发现,在调节条件下,随着神经反馈的运行,左 CEN 的募集增加,这一发现得到了 dlPFC 在调节条件下比观察条件下激活增加的支持。相比之下,DMN 任务负性募集在神经反馈运行期间保持稳定,尽管在观察条件下最高,并在休息期间增加(归一化)。关键的是,调节和观察条件下的 SN 募集都很高,这一发现可能表明 CEN 模式转换、适应性学习和 PTSD 中威胁/防御处理的增加。总之,这项研究提供了有启发性的初步证据,表明 PTSD 中使用 rt-fMRI-NFB 下调杏仁核与 ICN 的动态变化有关,这种效应类似于使用 EEG 模式的神经反馈观察到的效应。