Date of Award

August 2019

Degree Type


Degree Name

Doctor of Philosophy



First Advisor

Han Joo Lee

Committee Members

Shawn Cahill, Susan Lima, Raymond Fleming, Christine Larson


Cognitive Bias, Cognitive Bias Modification, Obsessive-Compulsive Disorder, Randomized Controlled Trial, Thought-Action Fusion


Found in many emotional disorders, thought-action fusion (TAF) is a distorted cognitive belief that simply having an upsetting intrusive thought can increase the chance of the associated event occurring (TAF Likelihood) or represents a person’s morality (TAF Morality). Challenging these beliefs through cognitive bias modification for interpretations (CBM-I) has been shown to modify negative interpretations, reduce TAF belief, and reduce associated distress. Our previous study (Siwiec, Davine, Kresser, Rohde, & Lee, 2017) showed that an active CBM-I developed to challenge TAF beliefs (TAF-INC) outperformed a control condition (TAF-CON) in reducing TAF belief, distress, and associated symptoms. The current study examined whether a single session of TAF-INC can outperform both TAF-CON, as well as a credible comparison condition, stress management psychoeducation (SMP). Fifty-seven non-clinical participants were randomized to either: (i) an active condition (TAF-INC), (ii) a control condition (TAF-CON), or (iii) a credible psychological comparison condition (SMP). SMP is part of many cognitive interventions for OCD and other anxiety disorders and has been shown to reduce obsession symptoms. Results from this study indicated that at post-training the TAF-INC condition experienced greater reductions in TAF scores, primary obsessions, and general distress than TAF-CON or SMP. At the 1-month follow-up the TAF-INC condition did not display consistently greater reductions than the other conditions. Results of the study are discussed in terms of the cognitive theory of obsessional thoughts, and future research directions are suggested.