Mindfulness plays an important role in moderating affect dynamics. To date, associations between mindfulness and affect dynamics have mostly been examined with mindfulness as a trait-like characteristic. However, examining associations between momentary mindfulness and affect dynamics could reveal important within-person processes underlying mindfulness and wellbeing. The present study first examined dispositional mindfulness as a 1-dimensional as well as a multifaceted construct in relation to affect dynamics (instability, inertia, and valence switch). We further investigated how momentary mindfulness predicts affect dynamics, and how training momentary mindfulness with a mindfulness training influences affect dynamics in daily life. A final sample of 125 undergraduate students took part in a 6-week randomized controlled trial, either engaging in a low-intensity mindfulness training (n = 61) or being part of a wait-list control condition (n = 64). We assessed participants' low and high arousal positive (PA) and negative affect (NA) and their momentary mindfulness 6 times a day for 40 consecutive days by implementing an ambulatory assessment (AA) protocol during either the mindfulness training or waiting period, respectively. We found that the dispositional mindfulness facet present-awareness was negatively associated with low arousal NA inertia and a lower switching propensity. However, we found momentary mindfulness to be positively associated with low arousal PA inertia, a lower switching propensity to NA and less instability. Furthermore, participants who practiced mindfulness experienced reduced low arousal NA inertia. These findings demonstrate that momentary mindfulness may be helpful in promoting adaptive affect experiences and maintaining PA, which could ultimately foster affective well-being. (PsycInfo Database Record (c) 2020 APA, all rights reserved).
Trial registration: ClinicalTrials.gov NCT02647801.