Rumination-Focused Cognitive Behavioral Therapy Versus Mindfulness-Based Cognitive Therapy in Treatment-Resistant Major Depressive Disorder: A Controlled Empirical Analysis of Ruminative Response Styles and Prefrontal Inhibitory Dysregulation

Abstract

Treatment-resistant major depressive disorder (TR-MDD) presents a substantial clinical burden, particularly when ruminative response styles perpetuate maladaptive prefrontal inhibitory dysregulation. This controlled empirical analysis examined 112 adults diagnosed with TR-MDD (DSM-5 criteria), randomized to either Rumination-Focused Cognitive Behavioral Therapy (RFCBT) or Mindfulness-Based Cognitive Therapy (MBCT) across a 16-week protocol. Primary outcomes included scores on the Ruminative Response Scale (RRS), Hamilton Depression Rating Scale (HDRS-17), and neurocognitive indices of executive inhibition measured via the Sustained Attention to Response Task (SART). RFCBT demonstrated significantly superior reductions in brooding rumination (d = 0.74, p < .001) and HDRS-17 scores compared to MBCT. Neurocognitive inhibitory deficits showed partial mediation of treatment outcomes. These findings support RFCBT as a preferential protocol for TR-MDD with prominent ruminative phenomenology.