Neurobiological Correlates in Augmentation of Effects of Psychotherapy for Depression

Cognitive behavioral therapy (CBT) was found to be an effective treatment for major depressive disorder (MDD) and CBT-related changes of dysfunctional neural activations were shown in recent studies. Despite these effects, remission rates after CBT are not sufficiently high in MDD and the integration of effective augmentation strategies is needed. In recent meta-analyses, endurance exercise was reported to be an effective intervention in MDD. However, underlying neural mechanisms of the anti-depressive effect of endurance exercise have been scarcely investigated to date, and a better knowledge of these mechanisms especially in combination with CBT is lacking.The main aim of this grant application is to investigate neural activation changes (by means of functional Magnetic Resonance Imaging) associated with the effects of endurance exercise in MDD for the first time and to show underlying mechanisms of the augmentation of CBT with endurance exercise. By applying a longitudinal randomized controlled study design, we investigate if a preceding endurance exercise intervention will increase the success-rate of a subsequent CBT and if this augmentation effect will be associated with specific neural activation changes. An active control group (low intensity endurance exercise) will be included to disentangle physiological from unspecific effects (e.g. general effects of an additional group activity or the attention of an exercise instructor). Specific aims of this study are the association of exercise-induced changes in cortisol and neurotrophine-levels with changes in neural activations during working memory, monetary incentive delay, and emotion-regulation tasks, as well as the prediction of CBT treatment response with these parameters. Results of this study may provide important implications for the development of effective treatment strategies in MDD, concerning the augmentation of CBT by endurance exercise.