Longitudinal MRI study of PTSD development from days to weeks after trauma

描述(由申请人提供)：创伤后应激障碍越来越被认为是一种常见的、致残的创伤后精神健康问题。神经影像研究表明，创伤后应激障碍与大脑功能和结构异常有关，但对这种异常的发展情况知之甚少。高级神经可塑性研究表明，成年人的大脑能够动态改变其功能和结构。根据这一证据，创伤后应激障碍可以被概念化为创伤适应不良的一种形式。目前的研究将通过测试创伤性机动车碰撞(MVC)后最初几周的渐进性变化来检验这一想法。工作假说是，患有创伤后应激障碍的幸存者和没有患上创伤后应激障碍的幸存者的大脑功能和结构在创伤后的早期几周会发生不同的变化。将对急诊科招募的MVC幸存者进行纵向研究，从最初几天(最多2周)开始，并在MVC后大约12周再次进行研究。在功能磁共振成像(FMRI)中，将使用重新评估情绪调节任务(RERT)和转移注意力情绪评估任务(SEAT)来研究与PTSD患者负性情绪下调的特征性缺陷相关的神经活动。此外，还将使用高分辨率结构磁共振(SMRI)扫描来检查皮质厚度。在最初几天和12周的扫描过程中，与情绪任务相关的激活和皮质厚度的差异将被用来定义在这段时间内的渐进性功能和结构变化。创伤后应激障碍幸存者和非创伤后应激障碍幸存者在进行性脑变化方面的差异将被用来确定导致创伤后应激障碍的大脑功能和结构的差异。这项拟议的工作填补了当前创伤后应激障碍发展模型中的一个重要空白，它确定了将创伤应激后的自然恢复与导致创伤后应激障碍的适应不良恢复区分开来的因素。这一发现有助于开发早期干预措施来预防和治疗创伤后应激障碍。已经收集了MVC幸存者在MVC后几天(9？4天)和12周内扫描的初步数据。初步结果表明，在创伤暴露组中，额叶和颞叶皮质厚度在最初几周内发生了变化，但在没有创伤的对照组中，在可比的时间间隔内没有变化。与情绪处理相关的大脑活动在左侧前额叶和视觉皮质增加，但在左侧缘上回和副海马区减少。这些初步结果提供了这段时期内几个大脑区域，包括FC区域的功能和结构变化的初步迹象。拟议的研究扩展了这项工作。

DESCRIPTION (provided by applicant): PTSD is increasingly recognized as a common, disabling mental health problem after trauma. Neuroimaging studies suggest that PTSD is related to abnormal brain function and structure, but the development of such abnormalities is poorly understood. Advanced neuroplasticity research demonstrates that the adult brain is capable of dynamically altering its function and structure. Based on this evidence, PTSD can be conceptualized as a form of maladaptation to trauma. The current study will examine this idea by testing for progressive changes during the initial weeks after a traumatic motor vehicle collision (MVC). The working hypothesis is that brain function and structure in survivors who do and in survivors who do not develop PTSD will change differently during the early post-trauma weeks. Survivors of MVCs recruited at the Emergency Department (ED) will be longitudinally studied, starting within the initial days (up to 2 weeks) and again at approximately 12 weeks after the MVC. Neural activity associated with characteristic deficits in down-regulation of negative emotion in PTSD patients will be studied using a Reappraisal Emotion Regulation Task (RERT) and a Shifted-attention Emotion Appraisal Task (SEAT) during functional magnetic resonance imaging (fMRI). In addition, high-resolution structural MRI (sMRI) scans will be used to examine cortical thickness. The differences in activation associated with emotional tasks and in cortical thickness between scan sessions at initial days and 12 weeks will be used to define progressive functional and structural changes over this period. Group differences in progressive brain changes in PTSD and non-PTSD survivors will be used to identify differences in brain function and structure that contribute to PTSD. The proposed work fills an important gap in current models of PTSD development by identifying factors that differentiate a natural recovery following traumatic stress from a maladaptive recovery that leads to PTSD. The findings can help develop early interventions to prevent and treat PTSD. Preliminary data have been collected from MVC survivors scanned within days (9¿4 days) and 12 weeks after an MVC. Preliminary results suggest that cortical thickness in frontal and temporal cortices changed over the initial weeks in trauma exposed groups, but not in trauma free controls over a comparable time interval. Brain activation associated with emotional processing increased in left prefrontal and visual cortices, but decreased in left supramarginal gyrus and parahippocampus. These preliminary results provide initial indications of functional and structural changes over this perid in several brain areas, including FC regions. The proposed research extends this work.