• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文学位 >Threat-induced Changes in Amygdala-Ventral Prefrontal Cortex Functional Connectivity and Risk for Posttraumatic Stress Disorder.
【24h】

Threat-induced Changes in Amygdala-Ventral Prefrontal Cortex Functional Connectivity and Risk for Posttraumatic Stress Disorder.

机译：威胁引起的杏仁核-前额叶皮层功能连接变化和创伤后应激障碍的风险。

获取原文
获取原文并翻译 | 示例
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

In a series of psychophysiology and functional magnetic resonance imaging (fMRI) experiments, we investigated threat-related changes in arousal and in the functional relationships of brain regions comprising critical neural circuitry in the cognitive regulation of emotion. We designed a novel paradigm to manipulate threat during a goal-directed task. We then validated this paradigm in separate neuroimaging and psychophysiological studies in healthy adults. In this paradigm, participants navigated a spatial maze to capture prey for monetary reward and avoid capture by a predator that would result in monetary losses. On threat trials, participants could receive unpredictable and inescapable shocks. On non-threat trials, participants would never be shocked. Visual cues were used to indicate whether the current trial was threat or non-threat. This paradigm was then used to study the cognitive regulation of emotion in trauma-exposed veterans with and without PTSD.;Our hypothesis was that participants would regulate the affective interference and associated anxiety caused by the threat of shock in order to maintain performance at a high level and thus maximize their monetary payout. We hypothesized that this regulation would be evident in the functional connectivity between the amygdala, a subcortical region involved in threat detection, and ventral prefrontal cortex (PFC) regions, which support executive functions. In Experiment 1 with healthy adults (N = 16), we used psychophysiological interaction (PPI) analyses to test task-specific changes in functional connectivity. We demonstrated increased functional connectivity for threat compared to non-threat conditions between the amygdala and ventral PFC regions, including the inferior frontal gyrus (IFG), orbitofrontal cortex (OFC), and ventromedial PFC (vmPFC).;We observed no behavioral performance differences related to our threat manipulation. Our preferred explanation, consistent with our regulation hypothesis, was that functional connectivity changes represented compensatory neural processing supporting the maintenance of goal-directed behavior during threat. However, the absence of behavioral performance differences related to threat is also consistent with an alternate hypothesis—namely, that our manipulation of threat was ineffective and participants did not experience increased arousal associated with affective interference and anxiety. This alternative explanation was explored in Experiment 2, in which we used psychophysiological measures to determine whether our threat induction that led to changes in functional connectivity was in fact associated with the expected increases in anxiety and arousal. In a separate sample of healthy adults (N = 26), we measured skin conductance and heart rate variability, both measures of sympathetic nervous system activation, and showed greater arousal for threat compared to non-threat conditions. This result further validated our threat manipulation.;In Experiment 3, we tested two groups of trauma-exposed veterans. One group consisted of individuals who received a current diagnosis of PTSD ( N = 20), whereas the other group did not have a current or past PTSD diagnosis (N = 22). We tested PTSD group differences in amygdala functional connectivity for threat compared to non-threat conditions with region-of-interest (ROI) analysis that used the functional clusters independently identified in Experiment 1 for bilateral IFG, vmPFC, anterior cingulate cortex, and mPFC/Brodmann area 10. This analysis showed a significant interaction in vmPFC in the expected direction, with greater increased amygdala functional connectivity strength for the threat condition compared to the non-threat condition in the non-PTSD group compared to the PTSD group.
机译：在一系列的心理生理和功能磁共振成像（fMRI）实验中，我们调查了与情绪相关的变化，包括情绪的认知调节中包括关键神经回路的大脑区域的觉醒和功能关系。我们设计了一种新颖的范式来控制目标任务中的威胁。然后，我们在健康成年人的单独的神经影像学和心理生理学研究中验证了这种范例。在这种范式中，参与者在空间迷宫中导航以捕获猎物以获得金钱奖励，并避免被捕食者捕获而导致金钱损失。在威胁试验中，参与者可能会受到无法预料和不可避免的冲击。在非威胁试验中，参与者永远不会感到震惊。视觉提示被用来指示当前的试验是威胁还是非威胁。然后将这种范例用于研究创伤性退伍军人在有或没有PTSD的情况下情绪的认知调节。我们的假设是参与者将调节休克威胁所引起的情感干扰和相关焦虑，以保持较高的表现。水平，从而最大化他们的货币支出。我们假设，在杏仁核（涉及威胁检测的皮层下区域）和支持执行功能的腹侧前额叶皮层（PFC）区域之间的功能连接中，这种调节是显而易见的。在健康成年人（N = 16）的实验1中，我们使用心理生理交互作用（PPI）分析来测试特定任务在功能连接性方面的变化。与非威胁条件相比，杏仁核和腹侧PFC区域（包括下额额回（IFG），眶额皮质（OFC）和腹侧PFC（vmPFC））之间的威胁相比，我们证明了功能连接的增强性;没有观察到行为表现差异与我们的威胁操纵有关。与我们的法规假设一致，我们的首选解释是功能连接性的变化代表了补偿性神经处理，支持了威胁期间维持目标导向行为。但是，没有与威胁相关的行为表现差异也与另一种假设一致，即我们对威胁的操纵无效，参与者没有因情感干扰和焦虑而引起的觉醒增加。在实验2中探索了这种替代性解释，其中我们使用了心理生理学方法来确定导致功能连通性改变的威胁诱导实际上是否与预期的焦虑和唤醒有关。在健康成年人（N = 26）的单独样本中，我们测量了皮肤电导率和心率变异性，这两种指标都是交感神经系统激活的量度，与非威胁条件相比，它表现出更大的威胁唤醒能力。该结果进一步验证了我们对威胁的操纵。在实验3中，我们测试了两组遭受外伤的退伍军人。一组由接受PTSD的当前诊断的患者组成（N = 20），而另一组则没有获得PTSD的当前或过去诊断（N = 22）。我们使用目标区域（ROI）分析测试了杏仁核在功能性连接方面的PTSD组与非威胁性条件相比的差异，该分析使用了实验1中针对双边IFG，vmPFC，前扣带回皮层和mPFC /布罗德曼地区10.该分析表明，与非PTSD组相比，非PTSD组中的威胁条件相比，针对威胁条件的杏仁核功能连通性强度在vmPFC方面具有显着的增加，而杏仁核功能连接强度的增加更大。

著录项

  • 作者

    Gold, Andrea Lillian.;

  • 作者单位

    Yale University.;

  • 授予单位 Yale University.;
  • 学科 Biology Neuroscience.;Psychology Clinical.
  • 学位 Ph.D.
  • 年度 2013
  • 页码 213 p.
  • 总页数 213
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类
  • 关键词

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号