Table_1_Effects of Brief Mindfulness Interventions on the Interference Induced by Experimental Heat Pain on Cognition in Healthy Individuals.DOCX

Background: Pain captures attention and interferes with competing tasks demanding cognitive effort. Brief mindfulness interventions involving both conceptual learning and meditation exercises have been shown to improve attention and reduce pain sensitivity, and could potentially reduce pain interference. This study assesses the effect of a 5-day mindfulness intervention (20 min/day) on the interference produced by thermal pain on working memory performance using a 2-back task.
Methods: Healthy participants were randomized into three groups exposed to mindfulness meditation training (n = 15), an active educational control intervention comprising only conceptual information on mindfulness (n = 15), or no intervention (n = 15). The two active interventions were administered in a dual-blind fashion and outcomes were assessed by research personnel blind to this allocation. Evaluation sessions were conducted before and after the interventions to assess the effect of pain on 2-back performance (pain interference). Importantly, both pain stimuli and the 2-back task were calibrated individually and in each session before assessing pain interference, thereby controlling for possible changes in baseline pain sensitivity and cognitive performance. Secondary outcomes included heat pain sensitivity, cold pain tolerance, cognitive inhibition, cognitive flexibility, and divided attention.
Results: Manipulation checks confirmed that heat pain interferes with the performance of the working-memory task. Compared to the no-intervention control group, pain interference was significantly reduced following the conceptual intervention but not the meditation intervention, although a corollary analysis suggests the effect might be due to regression toward the mean caused by baseline imbalance in pain interference. Secondary outcomes also suggested an increase in pain tolerance in the conceptual learning group only.
Discussion: A short mindfulness meditation intervention was insufficient to reduce pain interference but conceptual learning about mindfulness produced some unexpected benefits. Although the generalization of experimental findings to clinical pain conditions may be premature, these results highlight the importance of distinguishing the contribution of mindfulness education and meditation training in future studies. Understanding the effects of mindfulness training on pain regulation and management must take into consideration the multiple factors underlying this complex intervention.

研究背景：疼痛会抢占注意力，并干扰需要认知努力的竞争性任务。现有研究表明，兼具概念学习与冥想练习的简短正念（mindfulness）干预可改善注意力、降低疼痛敏感性，或能减轻疼痛干扰。本研究采用2-back任务（2-back task），评估为期5天、每日20分钟的正念干预对热痛干扰工作记忆表现的影响。
研究方法：将健康受试者随机分为三组：正念冥想训练组（n=15）、仅包含正念概念知识的主动教育对照干预组（n=15），以及无干预组（n=15）。两项主动干预均采用双盲方式实施，由对分组不知情的研究人员评估结局指标。分别在干预前后设置评估时段，以评估疼痛对2-back任务表现的影响（即疼痛干扰效应）。尤为重要的是，在评估疼痛干扰效应前，会针对每名受试者及每个评估时段分别校准疼痛刺激与2-back任务参数，以此控制基线疼痛敏感性与认知表现可能出现的变化。次要结局指标包括热痛敏感性、冷痛耐受力、认知抑制、认知灵活性与分配性注意力。
研究结果：操作检验证实，热痛会干扰工作记忆任务的表现。与无干预对照组相比，概念干预组的疼痛干扰效应显著降低，但冥想训练组未出现该变化；不过补充分析显示，该效应可能源于疼痛干扰基线失衡导致的均值回归现象。次要结局指标同样显示，仅概念学习组的疼痛耐受力有所提升。
讨论：简短的正念冥想干预不足以减轻疼痛干扰，但正念概念学习却带来了一些意外获益。尽管将本实验结果推广至临床疼痛情境尚为时过早，但本研究结果凸显了在未来研究中区分正念教育与冥想训练各自作用的重要性。要理解正念训练对疼痛调控与管理的作用，必须考虑这一复杂干预手段背后的多重影响因素。