Mindfulness-based interventions have gained extensive support for their application in the treatment of anxiety. However, their mechanisms remain largely unexplored. Excessive reactivity to uncertainty plays a central role in anxiety, and may represent a mechanism for the effect of mindfulness on anxiety, as mindfulness training fosters an open and accepting stance towards all aspects of experience. The present study sought to investigate both (i) self-reported intolerance of uncertainty (IU) as well as (ii) physiological and subjective responding to uncertain threat in a threat-of-shock paradigm, the NPU-threat test, as mediators for the relationship between mindfulness and anxiety in a cross-sectional study of healthy participants (N = 53). The results indicated that IU mediated the effect of mindfulness on some anxiety symptoms. In contrast, scores of physiological as well as subjective responses to uncertain threat from the NPU-threat test were largely unrelated to mindfulness, anxiety, or the IU self-report measure. The results provide initial evidence that reactions to uncertainty may play a role in the mindfulness-anxiety relationship and suggest that studies are needed to address how methodological variations of the NPU-threat test affect perceived levels of uncertainty and uncertainty-related anxiety.

基于正念的干预措施已广泛应用于焦虑症治疗。但是，它们的机制在很大程度上仍未开发。对不确定性的过度反应在焦虑中起着核心作用，并且可能代表了正念对焦虑的影响，因为正念训练对经验的各个方面都培养了开放和接受的态度。本研究试图调查（i）自我报告的不确定性不耐受（IU）以及（ii）冲击威胁范式（NPU-威胁测试）作为不确定因素的生理和主观应对不确定性威胁的媒介健康参与者的横断面研究中正念与焦虑之间的关系（N = 53）。结果表明，IU介导了正念对某些焦虑症状的影响。相比之下，NPU威胁测试对不确定威胁的生理和主观反应得分与正念，焦虑或IU自我报告测度基本无关。结果提供了初步的证据，表明对不确定性的反应可能在正念-焦虑关系中起作用，并建议需要进行研究以解决NPU威胁测试的方法变化如何影响不确定性和不确定性相关焦虑的感知水平。