The role of mindfulness in attenuating the adverse effects of daily negative events: An experience sampling study.

Mindfulness is robustly associated with psychological and physiological well-being. To date, studies have primarily focused on trait mindfulness while neglecting its state-level momentary regulatory effects on daily stress. This preregistered study investigated the effects of state mindfulness on participants’ momentary mood and physiological arousal in cohorts sampled between 2021 and 2024. Using the experience sampling method, 100 cohabiting couples (N = 200) completed five daily surveys for 16 days, and reported on their experiences of stressors (adverse events), state mindfulness levels, positive mood, and negative mood, while wearing Fitbit devices to monitor their heart rate. The registered analyses mainly demonstrated main effects (but no buffering effects) for state mindfulness. Specifically, state mindfulness predicted higher positive mood and lower heart rate among women. No association was found with negative mood, and state mindfulness did not moderate the relationship between stressors and stress response (mood and heart rate). However, secondary registered analyses, using a State Mindfulness Scale with more items, showed support for the mindfulness buffering effect, and indicated that negative events were associated with men’s heart rate when mindfulness was low. Overall, these results underscore the importance of studying state-level mindfulness and pave the way for future research on how momentary mindfulness can enhance emotion regulation, which in turn may help promote well-being in daily life.