The aim of this study is to investigate the effects of psychosocial stress on functional connectivity in relation to neuroendocrine markers in children and adolescents with depressive and comorbid anxiety disorders. The study will include 90 participants (n = 30 in each group) aged 11-19 years, divided into three groups: one group of patients with depressive disorder, another group of patients with depressive disorder and comorbid anxiety disorder, and a healthy control group. During the first appointment, participants will undergo a structured clinical examination and psychometric procedures. The second appointment will involve magnetic resonance imaging (MRI) scans to assess resting state functional connectivity before and after stress induction. Additionally, diffusion-weighted recordings (DTI) will be collected. Psychosocial stress will be induced using the established paradigm Montreal Imaging Stress Task (MIST), which requires participants to solve arithmetic tasks under social and time pressure. To assess brain activity during stress induction, task-based functional MRI scans will be conducted during both the control and experimental conditions of the MIST. Saliva samples will be collected from participants at various time points to analyze the hormones oxytocin (OXT) and cortisol (CORT). Differences in functional connectivity of fronto-limbic networks between all groups at rest are expected as well as changes in functional connectivity after stress induction associated with the release of OXT and CORT. Furthermore, psychometric procedures will provide insights into possible influencing factors. Overall, the study results aim to contribute to improved diagnostics and personalized treatment, providing valuable information for optimized treatment approaches.