The Neural Basis of Stress-Reactive Rumination: Investigating the Modulatory Effects of Theta-Burst Stimulation

Abstract

Ruminative thinking is a transdiagnostic process that plays a crucial role in psychopathology by prolonging the psychological and physiological stress response and exacerbating symptoms of depression and other conditions. Theta-Burst Stimulation (TBS) is a Non-Invasive Brain Stimulation technique that has been shown to modulate the affective, emotional and physiological response to stressors and alleviate symptomatology of, for instance, depressive disorders. To date, the underlying neural mechanisms of stress-reactive rumination have not been fully understood. TBS offers a promising tool to investigate the aforementioned processes and gain new insights to potentially improve treatment for mental disorders associated with ruminative thinking in the long term. Especially an aberrant functioning of the left Dorsolateral Prefrontal Cortex (DLPFC) has been repeatedly associated with depressive symptomatology and potentially ruminative thinking; however, it remains inconclusive to what extent the underlying neural correlates are similar or can be disentangled. While the first study of this dissertation examined brain activity to inform TBS research, the subsequent three studies applied TBS to gain deeper insights into the neural basis of stress-reactive rumination.