Extinction learning is regarded as a core mechanism underlying exposure therapy. The extent to which learned threats can be extinguished without conscious awareness is a controversial and on-going debate. We investigated whether implicit vs. explicit exposure to a threatened stimulus can modulate defence responses measured using pupillometry. Healthy participants underwent a threat conditioning paradigm in which one of the conditioned stimuli (CS) was perceptually suppressed using continuous flash suppression (CFS). Participants’ pupillary responses, CS pleasantness ratings, and trial-by-trial awareness of the CS were recorded. During Extinction, participants’ pupils dilated more in the trials in which they were unaware of the CS than in those in which they were aware of it (Cohen’s d = 0.57). After reinstatement, the percentage of fear recovery was greater for the CFS-suppressed CS than the CS with full awareness. The current study suggests that the modulation of fear responses by extinction with reduced visual awareness is weaker compared to extinction with full perceptual awareness.

消退学习被认为是暴露疗法的核心机制。习得的威胁在多大程度上可以在无意识的情况下被消除，这是一个有争议且持续存在的争论。我们研究了隐式与显式暴露于受威胁刺激是否可以调节使用瞳孔测量法测量的防御反应。健康参与者经历了威胁条件反射范式，其中使用连续闪光抑制（CFS）在感知上抑制条件刺激（CS）之一。记录参与者的瞳孔反应、CS 愉悦度评分以及逐次试验的 CS 意识。在“灭绝”期间，参与者的瞳孔在他们不知道 CS 的试验中比他们知道 CS 的试验中扩张得更多（Cohen's d = 0.57）。恢复后，CFS 抑制的 CS 的恐惧恢复百分比高于完全意识的 CS。目前的研究表明，与完全感知意识的消退相比，视觉意识减弱的消退对恐惧反应的调节较弱。