Klinke Christopher M, Lange Maren D, Andreatta Marta
Department of Biological Psychology, Clinical Psychology and Psychotherapy, University of Würzburg, Würzburg, Germany.
Institute of Physiology I, University Münster, Münster, Germany.
Neurobiol Stress. 2025 Mar 8;35:100715. doi: 10.1016/j.ynstr.2025.100715. eCollection 2025 Mar.
Intense and chronic stress strengthens fear memories and increases the risk for mental disorders. Often stressful situations are experienced long before the appearance of the symptoms, but so far, little has been investigated on how distal stress alters fear memories. In a four-day paradigm, 131 healthy individuals were either assigned to the stress-group by means of the socially evaluated cold-pressor test (SECPT) or to the sham-group (control condition). Twenty-four hours later, participants underwent fear acquisition during which two shapes were presented. The first shape (conditioned stimulus, CS+) was associated with an electro-tactile stimulation (unconditioned stimulus, US), whereas the second shape (CS-) were presented alone. During extinction training, both shapes were presented while the US was omitted. To investigate if stress induction alters extinction recall differently depending on the passage of time, participants were tested either one day (recent) or 15 days (remote) after extinction training. Learning was quantified via subjective ratings, startle reflex and skin conductance response. While we found successful acquisition and extinction of the conditioned defensive responses, there was no effect of stress on these learning processes. Stress induction did not alter the spontaneous recovery of the conditioned defensive verbal responses but of the physiological responses as stressed individuals tested two weeks after extinction training showed startle potentiation to CS + vs. CS-. In conclusion, distal stress, even if mild, can strengthen fear memories and weaken extinction memory by the passage of time. This could be a possible mechanism facilitating the onset of stress-related and anxiety disorders.
强烈且慢性的压力会强化恐惧记忆，并增加患精神障碍的风险。通常，压力情境在症状出现之前很久就已出现，但到目前为止，关于远期压力如何改变恐惧记忆的研究甚少。在一个为期四天的实验范式中，131名健康个体通过社会评价冷压试验（SECPT）被分配到压力组或假手术组（对照条件）。24小时后，参与者接受恐惧习得训练，期间呈现两种形状。第一种形状（条件刺激，CS+）与电触觉刺激（非条件刺激，US）相关联，而第二种形状（CS-）单独呈现。在消退训练期间，两种形状都呈现，但不施加非条件刺激。为了研究压力诱导是否会根据时间的推移对消退回忆产生不同影响，在消退训练后一天（近期）或15天（远期）对参与者进行测试。通过主观评分、惊跳反射和皮肤电导反应对学习进行量化。虽然我们发现条件防御反应成功习得和消退，但压力对这些学习过程没有影响。压力诱导并未改变条件防御性言语反应的自发恢复，但改变了生理反应，因为在消退训练两周后接受测试的受压力个体对CS+与CS-表现出惊跳增强。总之，远期压力即使轻微，也会随着时间的推移强化恐惧记忆并削弱消退记忆。这可能是促进与压力相关和焦虑症发病的一种可能机制。
