Orcutt Holly K, Hannan Susan M, Seligowski Antonia V, Jovanovic Tanja, Norrholm Seth D, Ressler Kerry J, McCanne Thomas
Department of Psychology, Northern Illinois University, DeKalb IL, USA.
Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta GA, USA.
Front Psychol. 2017 Jan 6;7:2031. doi: 10.3389/fpsyg.2016.02031. eCollection 2016.
Posttraumatic stress disorder (PTSD) is a common psychological disorder that affects a substantial minority of individuals. Previous research has suggested that PTSD can be partially explained as a disorder of impaired fear inhibition. The current study utilized a previously validated fear acquisition and extinction paradigm in a sample of 75 undergraduate women who were exposed to a campus mass shooting that occurred in 2008. We used a protocol in which conditioned fear was first acquired through the presentation of one colored shape (reinforced conditioned stimulus, CS+) that was paired with an aversive airblast to the larynx (unconditioned stimulus, US) and a different colored shape that was not paired with the airblast (non-reinforced conditioned stimulus, CS-). Fear was extinguished 10 min later through repeated presentations of the CSs without reinforcement. Number of clinically significant posttraumatic stress symptoms (PTSS) immediately following the mass shooting were positively associated with fear-potentiated startle (FPS) to the CS+ and CS- during late periods of acquisition. During early periods of fear extinction, PTSS was positively associated with FPS to the CS+. Results from the current study suggest that PTSS is related to altered fear inhibition and extinction during an FPS paradigm. In line with similar research, women with greater PTSS demonstrated a greater "fear load," suggesting that these women experienced elevated fear to the CS+ during extinction after conditioned fear was acquired.
创伤后应激障碍（PTSD）是一种常见的心理障碍，影响着相当一部分少数个体。先前的研究表明，PTSD可以部分解释为恐惧抑制受损的一种障碍。本研究在75名本科女生样本中采用了先前验证过的恐惧习得与消退范式，这些女生经历了2008年发生在校园的大规模枪击事件。我们使用了一种方案，其中条件性恐惧首先通过呈现一种彩色形状（强化条件刺激，CS+）来习得，该形状与喉部的厌恶性气吹（无条件刺激，US）配对，以及一种未与气吹配对的不同彩色形状（非强化条件刺激，CS-）。10分钟后，通过在没有强化的情况下重复呈现条件刺激来消除恐惧。大规模枪击事件后立即出现的具有临床意义的创伤后应激症状（PTSS）数量与习得后期对CS+和CS-的恐惧增强惊吓（FPS）呈正相关。在恐惧消退的早期，PTSS与对CS+的FPS呈正相关。本研究结果表明，PTSS与FPS范式中恐惧抑制和消退的改变有关。与类似研究一致，PTSS较高的女性表现出更大的“恐惧负荷”，这表明这些女性在习得条件性恐惧后，在消退过程中对CS+的恐惧有所增加。
