What to target? Interventions to modulate key mechanisms underlying the trajectories of affective disorders in the transregional Collaborative Research Center 393

Background Affective disorders are associated with an enormous disease burden, necessitating research on the mechanisms of effective treatments. Objectives This article introduces the intervention projects of the transregional Collaborative Research Center 393 (CRC/TRR 393). By employing targeted interventions, we aim to induce modifiability in the key mechanisms underlying the trajectories of affective disorders studied in CRC/TRR 393: emotion regulation, expectation, social cognition, and (circadian) cognitive–behavioral rhythms. Materials and methods The longitudinal design of the CRC/TRR 393 study will examine four interventions targeting specific mechanisms in subgroups of the German Mental Health Cohort (GEMCO). GEMCO includes patients with a current or lifetime diagnosis of major depressive disorder (MDD), bipolar disorder (BD), and healthy control (HC) participants. Multilevel measurements of these targeted mechanisms will allow us to investigate their fine-grained modifiability and their effects on disease trajectories. Results The results will provide insights into how these mechanisms can be modified. Together with the CRC/TRR 393 mechanisms projects, we will examine the effects of key cognitive–emotional mechanisms on disease trajectories. Conclusion For the first time, the modifiability of four key mechanisms underlying the trajectories of affective disorders will be investigated both cross-sectionally and longitudinally.