Clinical and Health Psychology, Utrecht University, The Netherlands; Department of Clinical Psychology, VU University Amsterdam, The Netherlands; EMGO Institute for Health and Care Research, The Netherlands.
J Psychiatr Res. 2013 Dec;47(12):1991-7. doi: 10.1016/j.jpsychires.2013.09.008. Epub 2013 Sep 20.
Recent cross-sectional studies have shown that the inability to suppress fear under safe conditions is a key problem in people with posttraumatic stress disorder (PTSD). The current longitudinal study examined whether individual differences in fear inhibition predict the persistence of PTSD symptoms. Approximately 2 months after deployment to Afghanistan, 144 trauma-exposed Dutch soldiers were administered a conditional discrimination task (AX+/BX-). In this paradigm, A, B, and X are neutral stimuli. X combined with A is paired with a shock (AX+ trials); X combined with B is not (BX- trials). Fear inhibition was measured (AB trials). Startle electromyogram responses and shock expectancy ratings were recorded. PTSD symptoms were measured at 2 months and at 9 months after deployment. Results showed that greater startle responses during AB trials in individuals who discriminated between danger (AX+) and safety (BX-) during conditioning, predicted higher PTSD symptoms at 2 months and 9 months post-deployment. The predictive effect at 9 months remained significant after controlling for critical incidents during previous deployments and PTSD symptoms at 2 months. Responses to AX+ or BX- trials, or discrimination learning (AX+ minus BX-) did not predict PTSD symptoms. It is concluded that impaired fear inhibition learning seems to be involved in the persistence of PTSD symptoms.
最近的横断面研究表明，在安全条件下无法抑制恐惧是创伤后应激障碍（PTSD）患者的一个关键问题。本纵向研究探讨了恐惧抑制的个体差异是否能预测 PTSD 症状的持续存在。大约在部署到阿富汗 2 个月后，144 名暴露于创伤的荷兰士兵接受了条件辨别任务（AX+/BX-）。在这个范式中，A、B 和 X 是中性刺激。X 与 A 结合会与电击配对（AX+ 试验）；X 与 B 结合不会（BX- 试验）。恐惧抑制是通过测量（AB 试验）来进行的。记录了惊跳肌电图反应和电击预期评分。在部署后 2 个月和 9 个月时测量 PTSD 症状。结果表明，在条件反射中区分危险（AX+）和安全（BX-）的个体在 AB 试验中惊跳反应越大，在部署后 2 个月和 9 个月时 PTSD 症状越高。在控制了之前部署期间的关键事件和 2 个月时的 PTSD 症状后，9 个月时的预测效应仍然显著。对 AX+或 BX-试验的反应，或辨别学习（AX+减去 BX-）均不能预测 PTSD 症状。结论是，受损的恐惧抑制学习似乎与 PTSD 症状的持续存在有关。
