Specific brain activation patterns during fear conditioning and the recall of previously extinguished fear responses have been associated with obsessive-compulsive disorder (OCD). However, further replication studies are necessary. We measured skin-conductance response and blood oxygenation level-dependent responses in unmedicated adult patients with OCD (n = 27) and healthy participants (n = 22) submitted to a two-day fear-conditioning experiment comprising fear conditioning, extinction (day 1) and extinction recall (day 2). During conditioning, groups differed regarding the skin conductance reactivity to the aversive stimulus (shock) and regarding the activation of the right opercular cortex, insular cortex, putamen, and lingual gyrus in response to conditioned stimuli. During extinction recall, patients with OCD had higher responses to stimuli and smaller differences between responses to conditioned and neutral stimuli. For the entire sample, the higher the response delta between conditioned and neutral stimuli, the greater the dACC activation for the same contrast during early extinction recall. While activation of the dACC predicted the average difference between responses to stimuli for the entire sample, groups did not differ regarding the activation of the dACC during extinction recall. Larger unmedicated samples might be necessary to replicate the previous findings reported in patients with OCD.

恐惧调节过程中特定的大脑激活模式以及对先前消失的恐惧反应的回忆与强迫症（OCD）有关。然而，还需要进一步的复制研究。我们测量了未接受药物治疗的成年强迫症患者 ( n  =  27) 和健康参与者 ( n  =  22) 的皮肤电导反应和血氧水平依赖性反应，这些受试者接受了为期两天的恐惧调节实验，包括恐惧调节、消退（第 1 天） ）和灭绝回忆（第二天）。在调节过程中，各组在皮肤电导对厌恶刺激（电击）的反应性以及右鳃盖皮层、岛叶皮层、壳核和舌回对条件刺激的反应方面存在差异。在消退回忆过程中，强迫症患者对刺激的反应较高，对条件刺激和中性刺激的反应差异较小。对于整个样本，条件刺激和中性刺激之间的响应增量越高，早期消退回忆期间相同对比的 dACC 激活就越大。虽然 dACC 的激活预测了整个样本对刺激反应之间的平均差异，但在消退回忆期间，各组在 dACC 的激活方面没有差异。可能需要更大的未用药样本来复制之前在强迫症患者中报告的研究结果。