PDF(Pubmed)
Abstract：
Fear conditioning paradigms are widely used in laboratory settings to discover treatments that enhance memory consolidation and various fear processes (extinction learning, limit return of fear) that are relevant targets of exposure-based therapies. However, traditional lab-based paradigms often use the exact same conditioned stimuli for acquisition and extinction (typically differentiated with a context manipulation), whereas the opposite is true in clinical settings, as exposure therapy rarely (if ever) uses precisely the exact same stimuli from an individual\'s learning history. Accordingly, this study utilized a novel three-day category-based fear conditioning protocol (that uses categories of non-repeating objects [animals and tools] as conditioned stimuli during fear conditioning and extinction) to determine if aerobic exercise enhances the consolidation of extinction learning (reduces return of fear) and memory (for items encoded during extinction) during subsequent tests of extinction recall. Participants (n=40) completed a fear acquisition (day 1), fear extinction (day 2), and extinction recall (day 3) protocol. On day 1, participants completed a fear acquisition task in which they were trained to associate a category of conditioned stimuli (CS+) with the occurrence of an unconditioned stimulus (US). On day 2, participants were administered a fear extinction procedure during which CS+ and CS- categorical stimuli were presented in absence of the occurrence of the US. After completing the task, participants were randomly assigned to either receive moderate-intensity aerobic exercise (EX) or a light-intensity control (CON) condition. On day 3, participants completed fear recall tests (during which day 1, day 2, and novel CS+ and CS- stimuli were presented). Fear responding was assessed via threat expectancy ratings and skin conductance responses (SCR). During the fear recall tests, the EX group reported significantly lower threat expectancy ratings to the CS+ and CS- and exhibited greater memory of CS+ and CS- stimuli that were previously presented during day 2. There were no significant group differences for SCR. These results suggests that administration of moderate-intensity aerobic exercise following extinction learning contributes to reduced threat expectancies during tests of fear recall and enhanced memory of items encoded during extinction.
摘要：
恐惧条件范式广泛用于实验室设置，以发现增强记忆巩固和各种恐惧过程的治疗方法（灭绝学习，限制恐惧的回归)，这是基于暴露的治疗的相关目标。然而,传统的基于实验室的范例通常使用完全相同的条件刺激进行采集和灭绝（通常通过上下文操作进行区分），而在临床环境中情况正好相反，因为暴露疗法很少（如果有的话）使用来自个体学习历史的完全相同的刺激。因此，这项研究利用了一项新的为期三天的基于类别的恐惧调节方案(该方案在恐惧调节和灭绝期间使用非重复对象[动物和工具]的类别作为条件刺激),以确定在随后的灭绝回忆测试中,有氧运动是否能增强灭绝学习(减少恐惧的返回)和记忆(对于在灭绝期间编码的项目)的巩固作用.参与者(n=40)完成了恐惧获取(第1天)，恐惧灭绝（第2天），和灭绝召回（第3天）协议。在第1天，参与者完成了一项恐惧获取任务，在该任务中，他们被训练将条件刺激（CS）的类别与非条件刺激（US）的发生相关联。在第2天，对参与者进行了恐惧消退程序，在此期间，在没有US发生的情况下出现CS和CS分类刺激。完成任务后,参与者被随机分配接受中等强度有氧运动(EX)或光强度控制(CON).在第3天，参与者完成了恐惧回忆测试（在第1天，第2天，以及新的CS和CS刺激）。通过威胁预期等级和皮肤电导反应（SCR）评估恐惧反应。在恐惧回忆测试中，EX组报告了对CS+和CS-的威胁预期评分明显较低,并且对先前在第2天出现的CS+和CS-刺激表现出更高的记忆.SCR没有显著的组间差异。这些结果表明，在灭绝学习后进行中等强度的有氧运动有助于减少恐惧回忆测试中的威胁预期，并增强了对灭绝期间编码项目的记忆。
