Fear inhibition in posttraumatic stress disorder

描述（由申请人提供）：创伤后应激障碍（PTSD）患者尽管存在安全信号，但仍存在持续的恐惧。虽然无法抑制恐惧是创伤后应激障碍的核心问题，但尚未得到很好的研究。本研究的目的之一是评估恐惧增强和恐惧抑制作为人类独立的过程。考虑到在许多不同的物种中都观察到这种现象，而且它的神经关联是众所周知的，这项研究将使用声惊吓反应的恐惧增强来衡量恐惧。研究的第一部分将翻译一个条件辨别程序（AX+/BX-），在动物中验证，以量化PTSD中的恐惧抑制。此外，我们将测试受试者是否在认知上意识到实验刺激之间的随变。先前的研究发现，应急意识在产生恐惧增强的惊吓中起着关键作用。本研究将探讨PTSD受试者的意识与惊吓是如何相互作用的。最后，本研究将探讨应急意识与恐惧抑制的关系。

DESCRIPTION (provided by applicant): Patients with posttraumatic stress disorder (PTSD) have persistent fear despite the presence of safety signals. Although the inability to inhibit fear is a central problem in PTSD, it has not been well studied. One of the goals of the present study is to assess fear potentiation and fear inhibition as independent processes in humans. This study will use fear potentiation of the acoustic startle response as a measure of fear, given that it has been observed across many different species and its neural correlates are well known. The first part of the study will translate a conditional discrimination procedure (AX+/BX-), validated in animals, in order to quantify fear inhibition in PTSD. Furthermore, we will test whether the subjects are cognitively aware of the contingencies between the experimental stimuli. Previous research has found that contingency awareness plays a key factor in developing fear-potentiated startle. The present study will investigate how awareness interacts with startle in PTSD subjects. Finally, the present study will examine the relationship between contingency awareness and fear inhibition.