Date of Award

January 2022

Document Type


Degree Name

Medical Doctor (MD)



First Advisor

Hedy Kober


Background: Fundamental and practical questions about mindfulness meditation remain inadequately addressed, including the dynamics of dose-response relationships and variables that moderate outcomes of mindfulness-based interventions. The present study aims to help elucidate dose-response and moderating relationships on various state-level measures of psychological wellbeing in the context of single-session mindfulness-based interventions.

Methods: 372 participants completed online questionnaires assessing trait neuroticism and trait mindfulness as well as state levels of mindfulness, anxiety, and positive and negative affect before being randomly assigned to one of four conditions: a ten-minute mindfulness meditation, a twenty-minute mindfulness meditation, or control conditions of the aforementioned durations that involved listening to a recording of a National Geographic article. Following the intervention, participants completed the same state-level questionnaires as well as questions assessing self-efficacy.

Results: Participants in both mindfulness conditions experienced significant within-group improvements in state mindfulness and state anxiety, with the twenty-minute group also experiencing a significant decrease in negative affect. Notably, there were no significant differences between the two meditation conditions. The only between-group difference occurred between the ten-minute mindfulness and ten-minute control condition, with the former experiencing a greater increase in state mindfulness. Compared to participants in the control conditions, participants in the mindfulness conditions experienced significantly greater increases in state mindfulness. Neuroticism, self-efficacy, and trait mindfulness were found to moderate many of the outcomes, with higher neuroticism and self-efficacy and lower trait mindfulness typically correlating with greater improvements.

Conclusion: We found evidence supporting the beneficial effects of brief mindfulness meditation and that neuroticism, self-efficacy, and trait mindfulness moderated these effects. However, we did not find evidence of dose-related effects in mindfulness meditation when comparing ten versus twenty minutes. Future research will hopefully further explore these phenomena in single- and multi-session mindfulness-based interventions and with additional “doses.”


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