Doctor of Philosophy
Date of Defense
Steven E. Bruce, Ph.D.
The utilization of functional magnetic resonance imaging (fMRI) techniques to examine biomarkers and neural activity patterns related to posttraumatic stress disorder (PTSD) has provided a way to investigate mechanisms that underlie the development, maintenance, and recovery from PTSD. Studying the neural correlates of individual differences related to transdiagnostic factors has the potential to provide clinically relevant information beyond that of diagnostic categories. Rumination is one such factor. Rumination, defined as repetitive, negative, self-focused thinking is considered to be a transdiagnostic factor that is associated with depression, anxiety, and PTSD. In individuals with PTSD, rumination serves as a cognitive avoidance factor that contributes to the maintenance of symptoms by interfering with the cognitive and emotional processing of the traumatic event and it may interfere with treatment engagement and outcome. Little is known regarding the neural correlates of rumination in individuals with PTSD. The current study examined self-reported rumination in women with PTSD. Functional MRI (fMRI) was used to investigate the neural substrates of rumination in treatment seeking women with PTSD and the relationship between change in rumination and change neural activity across treatment. The relationship between rumination and treatment outcome was also examined. Participants included 39 women with PTSD, 17 women with trauma exposure and no PTSD, and 18 healthy controls recruited through a university-based trauma clinic. Results found that women with PTSD experienced greater levels of ruminative thought than women in the trauma exposed no PTSD or healthy control groups (F(2, 71) = 28.24, p < .001, η2 = .443). At the end of Cognitive Processing Therapy, participants had a significant decrease in the level of rumination that they reported (t(19) = 4.693, p (two tailed) < .001, d = 1.05). The fMRI findings evidenced a significant relationship between self-reported rumination and areas related to emotion generation and control. Findings did not generally support a relationship between pretreatment self-reported rumination and treatment outcome. Further, the activation of brain regions related to pretreatment rumination did not predict treatment outcome.
Buchholz, Katherine Ruth, "Neural Correlates of Rumination in Posttraumatic Stress Disorder Before and After Cognitive Processing Therapy" (2015). Dissertations. 165.