Dipartimento di Scienze Cognitive, Psicologiche, Pedagogiche e Degli Studi Culturali, Università Degli Studi di Messina, 98121 Messina, Italy.
Department of Psychology and Neurosciences, Leibniz Research Center for Working Environment and Human Factors, Ardeystr. 67, 44139 Dortmund, Germany.
J Affect Disord. 2022 Aug 15;311:344-352. doi: 10.1016/j.jad.2022.05.033. Epub 2022 May 11.
Circadian rhythms have received increasing attention within the context of mental disorders. Evening chronotype has been associated with enhanced risk to develop anxiety and post-traumatic stress disorder (PTSD). The classical fear conditioning paradigm is a powerful tool to reveal key mechanisms of anxiety and PTSD. We used this paradigm to study the neurocognitive basis of the association between chronotype and fear responses in healthy humans. 20 participants with evening chronotype and 20 controls (i.e., intermediate chronotype) completed a 2-day Pavlovian fear learning and extinction virtual reality task. Participants received fear conditioning, and extinction learning on day 1. Extinction memory recall was tested on day 2. To address interactions between chronotype and time of day of the fear conditioning, and extinction performance, half of the participants were tested in the morning, and the other half in the evening. Skin conductance response (SCR) and subjective fear ratings were measured as primary outcomes. Chronotype was established via the morningness-eveningness questionnaire (MEQ). We found an overall higher SCR for fear acquisition in participants with the evening chronotype profile, compared to controls. Moreover, the higher the MEQ scores -indicative of less eveningness - the lower the SCR was. No effects of chronotype were found for extinction and extinction recall. The higher vulnerability of the evening chronotype for anxiety and related disorders may thus be explained by enhanced fear acquisition of this group.
昼夜节律在精神障碍的背景下受到越来越多的关注。晚型作息与焦虑和创伤后应激障碍（PTSD）的风险增加有关。经典的恐惧条件反射范式是揭示焦虑和 PTSD 关键机制的有力工具。我们使用该范式研究了健康人群中昼夜节律与恐惧反应之间关联的神经认知基础。20 名晚型作息的参与者和 20 名对照（即中间型作息）完成了为期两天的 Pavlovian 恐惧学习和消退虚拟现实任务。参与者在第 1 天接受恐惧条件反射和消退学习。在第 2 天测试消退记忆回忆。为了解决恐惧条件反射和消退表现的昼夜节律和时间之间的相互作用，一半的参与者在早上进行测试，另一半在晚上进行测试。皮肤电反应（SCR）和主观恐惧评分作为主要结果进行测量。昼夜节律通过晨型-晚型问卷（MEQ）确定。我们发现，与对照组相比，晚型作息的参与者在恐惧获得方面的 SCR 总体较高。此外，MEQ 得分越高——表明傍晚的程度越低——SCR 越低。对于消退和消退回忆，没有发现昼夜节律的影响。晚型作息对焦虑和相关障碍的更高易感性可能可以通过该组增强的恐惧获得来解释。
