Revisiting the Monitoring and Acceptance Theory: Findings from a Daily Diary, Three-Armed Randomized Controlled Trial

Based on the Monitor and Acceptance Theory (MAT), mindfulness interventions influence psychological wellbeing in two ways: (a) monitoring increases emotional responses (intensifies both positive and negative affect), while (b) acceptance must interact with monitoring to attenuate negative emotions and enhance positive emotions. Yet, cross-sectional and longitudinal evidence supporting these two tenets are inconsistent. Using multilevel structural equation modelling, this study evaluated these tenets by examining the independent mediating effects of monitoring and acceptance on affective and interpersonal outcomes across time.

One hundred six individuals with no prior meditation experience were randomly assigned into a 14-day “Monitoring-Only” brief meditation, 14-day “Monitoring + Acceptance” brief meditation, or no-treatment control group. Multilevel mediation models were conducted to test if changes in monitoring or acceptance across the intervention period (Day 8—Day 21) fully mediated improvements in affect and social connectedness during the same period, while controlling for baseline outcomes (Day 1—Day 7). These models were repeated for follow-up variables (Day 22—Day 28) to examine the same longitudinal relationships.

During both the intervention and follow-up periods, Monitoring and Acceptance skills independently mediated the improvements in positive affect and social connectedness. Monitoring skills mediated reductions in negative affect only at high levels of Acceptance, while Acceptance skills mediated reductions in negative affect only at moderate to high levels of Monitoring.

The present study suggests revision to the existing MAT tenets. In line with MAT predictions, both Monitoring and Acceptance skills interact to reduce negative emotions. However, contrary to MAT predictions, Monitoring skills did not exacerbate negative affect, and Acceptance skills independently improved emotional and interpersonal outcomes.

This study is not preregistered.