Category: Adult Depression / Dysthymia
Interpretation Bias Modification (IBM) is gaining attention in the literature as an intervention that alters cognitive biases and reduces associated symptoms. Hostile interpretation bias is a specific negative cognitive bias that reflects an individual’s tendency to assume hostile or aggressive intent behind the actions of others (Hawkins & Cougle, 2013). Smith and colleagues (2016) published findings showing elevations of hostile interpretation bias in a clinically depressed sample. In the present study, 40 adults with major depressive disorder (MDD) were randomly assigned to receive either IBM targeting hostile interpretation bias (IBM-H) or a healthy video control (HVC) condition. Compared to those in HVC, participants in IBM-H reported more benign interpretations (Wald (1, 40) = 39.54, β = .49, p < .001) and fewer hostile interpretations (Wald (1, 40) = 1.16, β = -.305, p = .026) at post-treatment. No difference in depressive interpretation bias was found between groups at post-treatment (Wald (1, 40) = 6.09, β = .08, p = .62). IBM-H led to greater anger control at post-treatment (Wald (1, 40) = 102.50, β = .733, p = .03) and follow-up (Wald (1, 40) = 4.31, β = .332, p = .006) compared to HVC. The IBM-H group perceived their treatment as less credible than the HVC group (F (1, 40) = 5.56, p = .024, η² = .13). For individuals with high expectancy of treatment success, IBM-H led to lower post-treatment depressive symptoms compared to HVC (Wald (1,40) = 13.62, β= -.35, p = .05), while findings trended in the opposite direction for those with low expectancy of success (Wald (1,40) = 13.24, β= .31, p = .08). Overall, the findings of this study contribute to understanding the efficacy of IBM protocols for anger and depression and highlight potential improvements to be made to future IBM protocols.