Remembering an unfamiliar person and the contextual conditions of that encounter is important for adaptive future behavior, especially in a potentially dangerous situation. Initiating defensive behavior in the presence of former dangerous circumstances can be crucial. Recent studies showed selective electrocortical processing of faces that were previously seen in a threat context compared to a safety context, however, this was not reflected in conscious recognition performance. Here, we investigated whether previously seen threat-faces, that could not be remembered, were capable to activate defensive psychophysiological response systems. During an encoding phase, 50 participants with low to moderate levels of anxiety viewed 40 face pictures with neutral expressions (6 s each), without an explicit learning instruction (incidental learning task). Each half of the faces were presented with contextual background colors that signaled either threat-of-shock or safety. In the recognition phase, all old and additional new faces (total of 60) were presented intermixed without context information. Participants had to decide whether a face was new or had been presented previously in a threatening or a safe context. Results show moderate face recognition independent of context conditions. Startle reflex and skin conductance responses (SCR) were more pronounced for threat compared to safety during encoding. For SCR, this differentiation was enhanced with higher levels of depression and anxiety. There were no differential startle reflex or SCR effects during recognition. From a clinical perspective, these findings do not support the notion that perceptual biases and physiological arousal directly relate to threat-associated identity recognition deficits in healthy and clinical participants with anxiety and trauma-related disorders.

记住一个陌生的人以及这次相遇的背景条件对于适应未来的行为很重要，尤其是在潜在危险的情况下。在以前的危险情况下启动防御行为可能至关重要。最近的研究表明，与安全环境相比，对先前在威胁环境中看到的面孔进行选择性电皮层处理，然而，这并没有反映在有意识的识别表现中。在这里，我们调查了以前看到的、无法记住的威胁面孔是否能够激活防御性心理生理反应系统。在编码阶段，50 名具有低度到中度焦虑的参与者观看了 40 张表情中性的脸部图片（每张 6 秒），没有明确的学习指导（附带学习任务）。每半张脸都呈现出上下文背景颜色，表示电击威胁或安全。在识别阶段，所有旧面孔和额外的新面孔（总共 60 个）在没有上下文信息的情况下混合呈现。参与者必须决定一张脸是新的还是之前在威胁或安全的环境中出现过。结果显示，人脸识别程度适中，与环境条件无关。与编码过程中的安全相比，惊吓反射和皮肤电导反应（SCR）对于威胁的影响更为明显。对于 SCR，这种差异随着抑郁和焦虑水平的升高而增强。识别过程中没有差异惊吓反射或 SCR 效应。从临床角度来看，这些发现并不支持以下观点：对于患有焦虑和创伤相关疾病的健康和临床参与者，知觉偏差和生理唤醒与威胁相关的身份识别缺陷直接相关。