An experimental investigation of the effects and mechanisms of mindfulness meditation versus self-hypnosis versus an attention control on cold pressor outcomes

Objectives: This research examined whether brief sessions of mindfulness meditation (MM) or self-hypnosis (HYP) produce changes in cold pressor task (CPT) outcomes and whether outcome improvement, when it occurs, is mediated by attentional processes (i.e., pain focus, mindful observing) or pain appraisals (i.e., threat, challenge). Methods: Healthy adults (N = 201) were randomly assigned to 20-min sessions of MM, HYP, or an attention Control. Participants completed assessments of potential mediators before the first CPT and after experimental intervention, but before a second CPT. Results: HYP and MM participants reported greater reductions in CPT pain intensity than Control participants, and CPT unpleasantness was reduced in HYP compared to Control. Neither MM nor HYP resulted in significant changes in pain focus or mindful observing, and these scales were not associated with CPT outcomes. However, threat appraisals were reduced in HYP versus Control, and threat appraisal reductions were associated with increased pain tolerance. Challenge appraisal increased in both HYP versus Control and HYP versus MM, and challenge increases were associated with reductions in CPT unpleasantness. Challenge changes were a significant mediator of unpleasantness changes when HYP was compared to MM (p =.042); this mediation effect was non-significant for HYP compared to Control (p =.059). Conclusions: The findings indicate single sessions of HYP and MM produce changes in CPT outcomes. HYP also influenced threat and challenge appraisals, which were associated with CPT outcome changes, and challenge appraisals emerged as a potential mechanism of HYP. Further research is needed to identify mediating mechanisms for these two pain management approaches.