Change of Neural Network Indicators through Narrative Treatment of PTSD in Torture Victims

目前关于创伤后应激障碍(PTSD)的理论是基于创伤事件的病理记忆表征来解释这种障碍的症状。根据这些理论，创伤事件有两种不同的病理表现。恐惧结构是连接创伤情境的感觉、情绪和身体特征的联想神经网络。另一方面，在自传体记忆中，对创伤事件的再现是杂乱无章和不全面的。创伤后侵扰是由于当一个人被提醒时恐惧结构的不受控制的活动造成的。自传体表征的碎片化导致缺乏足够的时间和空间背景信息，阻碍了恐惧结构的大脑皮层调节和抑制。创伤后应激障碍的治疗通常包括详细地谈论创伤事件。目前还不清楚这一过程是对恐惧结构起作用，还是对自传体记忆起作用。该项目的目标是验证这样一种假设，即治疗促进的康复不会改变最初的恐惧结构，而是建立一种依赖于语言活动的抑制机制。在脑磁图(MEG)中使用积极、厌恶和中性图片刺激的情感视觉稳态范式将被用来研究情绪刺激处理的空间和时间模式。为了检验治疗的效果，这一范例将被用作叙述性暴露疗法的随机对照试验和严重创伤酷刑受害者的等待名单控制条件下的结果衡量标准。

Current theories of posttraumatic stress disorder (PTSD) explain the symptoms of this disorder on the basis of pathological memory representations of the traumatic event. According to these theories there are two different pathological representations of the traumatic event. The fear structure is an associative neural network connecting the sensory, emotional and physical features of the traumatic situation. On the other hand there is a disorganized and incomprehensive representation of the traumatic event in autobiographical memory. Posttraumatic intrusions result from an uncontrolled activity of the fear structure when a person is reminded of the event. The lack of adequate temporal and spatial context information caused by the fragmented autobiographical representation prevents a cortical regulation and inhibition of the fear structure. Treatment of PTSD generally involves talking about the traumatic event in detail. It is unclear whether this process acts upon the fear structure or on autobiographical memory. The goal of the project is to test the hypothesis that treatment-facilitated recovery does not change the original fear structure but establishes an inhibitory mechanism that depends on verbal activity. An affective visual steady-state paradigm in magnetencephalography (MEG) using positive, aversive and neutral picture stimuli will be used to examine the spatial and temporal pattern of the processing of emotional stimuli. To examine the effects of treatment this paradigm will be used as outcome measure within a randomized controlled trial of Narrative Exposure Therapy and a waitinglist control condition for severely traumatized torture victims.