Pile Victoria, Barnhofer Thorsten, Wild Jennifer
Department of Psychology, Institute of Psychiatry, King's College London, London, United Kingdom.
Department of Experimental Psychology, University of Oxford, Oxford, United Kingdom.
PLoS One. 2015 Apr 22;10(4):e0122971. doi: 10.1371/journal.pone.0122971. eCollection 2015.
Targeting the consolidation of fear memories following trauma may offer a promising method for preventing the development of flashbacks and other unwanted re-experiencing symptoms that characterise Posttraumatic Stress Disorder (PTSD). Research has demonstrated that performing visuo-spatial tasks after analogue trauma can block the consolidation of fear memory and reduce the frequency of flashbacks. However, no research has yet used verbal techniques to alter memories during the consolidation window. This is surprising given that the most effective treatments for PTSD are verbally-based with exposure therapy and trauma-focused cognitive behavioural therapy gaining the most evidence of efficacy. Psychological therapies aim to reduce the conditioned fear response, which is in keeping with the preliminary finding that an increased propensity for fear conditioning may be a vulnerability factor for PTSD. Our research had two aims. We investigated the degree to which individual differences in fear conditioning predict the development of PTSD symptoms. We also compared the preventative effects of two clinically informed psychological techniques administered during the consolidation window: exposure to the trauma memory and updating the meaning of the trauma. 115 healthy participants underwent a fear conditioning paradigm in which traumatic film stimuli (unconditioned stimuli) were paired with neutral stimuli (conditioned stimuli). Participants were randomly allocated to an updating, exposure or control group to compare the effects on the conditioned fear response and on PTSD symptomatology. The results showed that stronger conditioned responses at acquisition significantly predicted the development of PTSD symptoms. The updating group, who verbally devalued the unconditioned stimulus within the consolidation window, experienced significantly lower levels of PTSD symptoms during follow-up than the exposure and control groups. These findings are consistent with clinical interventions for chronic PTSD and have important implications for identifying those at risk as well as for designing novel early interventions to prevent the development of PTSD.
针对创伤后恐惧记忆的巩固进行干预，可能为预防创伤后应激障碍（PTSD）所特有的闪回及其他不良的再次体验症状的发展提供一种有前景的方法。研究表明，在模拟创伤后执行视觉空间任务可以阻断恐惧记忆的巩固，并减少闪回的频率。然而，尚无研究使用言语技术在巩固期改变记忆。鉴于PTSD最有效的治疗方法是以言语为基础的，暴露疗法和以创伤为重点的认知行为疗法获得了最多的疗效证据，这一点令人惊讶。心理治疗旨在减少条件性恐惧反应，这与初步研究结果一致，即恐惧条件作用倾向增加可能是PTSD的一个易患因素。我们的研究有两个目的。我们调查了恐惧条件作用中的个体差异在多大程度上预测PTSD症状的发展。我们还比较了在巩固期实施的两种基于临床的心理技术的预防效果：暴露于创伤记忆和更新创伤的意义。115名健康参与者接受了恐惧条件作用范式，其中创伤性电影刺激（无条件刺激）与中性刺激（条件刺激）配对。参与者被随机分配到更新组、暴露组或对照组，以比较对条件性恐惧反应和PTSD症状的影响。结果表明，习得时较强的条件反应显著预测了PTSD症状的发展。在巩固期内通过言语贬低无条件刺激的更新组，在随访期间经历的PTSD症状水平明显低于暴露组和对照组。这些发现与慢性PTSD的临床干预一致，对于识别有风险的人群以及设计新的早期干预措施以预防PTSD的发展具有重要意义。
