Date of Award


Degree Name

Doctor of Philosophy



First Advisor

Rodriguez, Benjamin

Second Advisor

Gilbert, David


Mindfulness practice is associated with reduced anxiety, enhanced tolerance of negative affect, lower stress reactivity, improved task concentration, increased cognitive flexibility, and enhanced neurological functioning. However, mindfulness-based treatments are highly varied in duration, type and extent or training provided, and treatment focus. Studies of mindfulness interventions also often fail to operationally define mindfulness, which poses a challenging for understanding the mechanism(s) of change involved in its anxiolytic effects. In the current study, attentional control was examined as a possible mechanism of change, as it is largely deficient in individuals with anxiety yet necessary for extinction learning in treatment. In theory, mindfulness interventions can facilitate increased attentional control during exposure tasks, thereby enhancing new learning and eventually improving treatment outcomes. Using a randomized controlled design, the current study aimed to investigate the effects of mindfulness on attentional control for anxious individuals, with a specific examination of two types of mindfulness exercises: mindful physiological awareness and mindful acceptance. 142 participants were recruited from undergraduate psychology classes at Southern Illinois University, of which 63 had moderate-high trait anxiety and 79 had low trait anxiety (per STAI-Trait score). All participants completed baseline self-report questionnaires, after which they completed a mixed saccade task followed by listening to a 15-minute audio-recorded intervention based on group assignment. Finally, they completed a post-test mixed saccade task and post-test self-report questionnaires. It was hypothesized that both mindfulness groups would demonstrate significantly improved inhibition and shifting processing efficiencies compared to a mind wandering control, and that the mindful acceptance group would demonstrate significantly greater gains than the mindful physiological awareness group. Minimal differences in performance effectiveness were expected among all groups. Contrary to hypotheses, results indicated no significant effects of group on inhibition and shifting processing efficiencies or performance effectiveness in the anxious subsample. However, in the non-anxious subsample, the mindful acceptance group had shorter reaction times than the other two groups and the mindful physiological awareness group had higher accuracy rates than the control group. Findings suggest anxious individuals may need more extensive mindfulness practice to improve attentional control, as they tend to display greater attention deficits than non-anxious individuals. However, the study was limited in sample size and further research and study replication is needed prior to making conclusions about whether attentional control is a true mechanism of change. Study limitations, strengths, and future directions for study are also discussed.




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