Background and objectives

In dual-tasking, individuals recall a threat-related memory while performing a demanding dual-task. This is a fruitful approach to reduce the unpleasantness and vividness of aversive memories and to reduce conditioned fear responses. Crucially, it remains unclear whether dual-tasking can also reduce conditioned fear responses and intrusive memories over time. In this pre-registered two-day fear conditioning paradigm, we examined whether a dual-task intervention reduces return of fear and the frequency of intrusive memories of an aversive film over time.

Methods

On Day 1, 76 healthy participants underwent fear acquisition with aversive film clips. They were then randomly allocated to one of three conditions: dual-tasking, memory recall without a dual-task (‘recall only’), or no task. Afterwards, they underwent an extinction phase and were asked to record intrusive film memories over 48 h. On Day 3, return of fear was assessed.

Results

On Day 1, fear acquisition and extinction were successful. On Day 3, spontaneous recovery and renewal were evident, but, overall, participants reported few intrusions. The dual-task and recall only groups reported reduced unpleasantness of threat memory compared to the no task group, but they did not show reduced (return of) fear responses or fewer intrusions.

Limitations

Intrusion frequency was low in all three groups, which limits the detection of intervention effects.

Conclusions

Even though dual-tasking and recall only devalued threat memory temporarily compared to no task, these interventions did not reduce (return of) fear responses and intrusions. Future studies could focus on improving the potency of imagery-based interventions.

中文翻译：

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通过双重任务干预威胁记忆贬值：测试 48 小时内恐惧和侵入性记忆的恢复

背景和目标

在双重任务中，个人在执行要求很高的双重任务时会回忆起与威胁相关的记忆。这是减少厌恶记忆的不愉快和生动并减少条件性恐惧反应的有效方法。至关重要的是，随着时间的推移，双重任务是否也能减少条件性恐惧反应和侵入性记忆仍不清楚。在这个预先注册的为期两天的恐惧条件反射范式中，我们检查了双任务干预是否会随着时间的推移减少恐惧的回归和厌恶电影的侵入性记忆的频率。

方法

在第 1 天，76 名健康参与者通过厌恶的电影剪辑进行了恐惧获取。然后他们被随机分配到三个条件之一：双重任务、没有双重任务的记忆召回（“仅召回”）或没有任务。之后，他们经历了灭绝阶段，并被要求在 48 小时内记录侵入性电影记忆。在第 3 天，评估恐惧的回归。

结果

第 1 天，恐惧获得和消除成功。在第 3 天，自发恢复和更新很明显，但总体而言，参与者报告的入侵很少。与无任务组相比，双任务组和仅回忆组报告了威胁记忆的不愉快减少，但他们没有表现出减少（返回）恐惧反应或更少的入侵。

限制

三组的干预频率均较低，这限制了干预效果的检测。

结论

尽管与没有任务相比，双重任务和回忆只会暂时贬低威胁记忆，但这些干预并没有减少（回归）恐惧反应和入侵。未来的研究可以集中在提高基于图像的干预措施的效力上。