Mindfulness Based Emotion Regulation Therapy in the Treatment of Depressive Rumination

In this study the investigators are examining the neuronal processes of a mindfulness based emotion regulation training for reducing depressive rumination. The research of depressive rumination helps in the developement of new therapies for depressive disorders.

Goal of this project is to have a look at the coherences between stress, mindfulness resources, depressive rumination and their neuronal correlates. Therefore the investigators are collecting the data of 48 patients with a depressive diagnosis in a randomized intervention-study with a treatment as usual (TAU) waiting-control-list versus an active intervention group. An additional 48 healthy control subjects are planned to be measured.

In a randomized and (for gender and severity of depressive symptomatic) outbalanced design the investigators are examining the neuronal processes of a mindfulness based emotion regulation training (MBERT) for reducing depressive rumination in a cross-over design.

Therefore 48 patients with a depressive disorder get a MBERT that consists of one psychoeducative session and 8 therapy sessions.

For checking the efficacy of the MBERT each patient runs three times through the Trier Social Stress Test (TSST). As the study design is a cross-over design, half of the patients get the MBERT in block 1 (i.e. between the first and the second TSST) and half of the patients get the MBERT in block 2 (i.e. between the second and the third TSST). In the block where they don't receive the MBERT the patients don't get any treatment within the scope of the study (waiting period), but any treatment as usual (TAU), including pharmacotherapy and psychotherapy, can be continued and started at each point of the study.

For analyzing the neuronal processes the investigators are measuring the cerebral oxygenation using functional near-infrared-spectroscopy (fNIRS) during the TSSTs as well as during the 8 therapy sessions.

Using an ecological momentary assessment (EMA), the investigators additionally are collecting data of the actual stress level, stressful events, rumination, equanimity, self-compassion, mindfulness and sleep quality two times a day. Thus the investigators can (1) observe the individual reaction to stress in the daily life, and (2) recheck if the patients are able to transfer the learned strategies from the MBERT in their daily life. For those patients that received the MBERT in the first block the investigators (3) additionally have data to evaluate the sustainability (i.e. the lasting effectivity) of the MBERT.

As a control condition, 48 healthy subjects will get a single TSST session.

Eligibility Criteria:
Inclusion Criteria:

* age: 18-60
* german as mother tongue
* diagnosis of a unipolar depressive disorder
* ruminative processes in the psychopathology

Exclusion Criteria:

* pregnancy
* acute or chronic disorder or medical treatment of such that might influence the cerebral metabolism:
* Diabetes mellitus (E10-E14 in ICD-10)
* Renal insufficiency apart from stadium 3 in Kidney Disease Outcomes Quality Initiative
* non adjusted hypertonus (I10.x in ICD-10)
* medium-severe or severe craniocerebral injury (GCS 3-12) / craniocerebral injury of 2. or 3. degree with loss of consciousness of \> 30 minutes
* any medication except oral contraceptives
* other axis-I / axis-II disorders as main diagnosis
* comorbid neurological disease
* psychotic symptoms
* acute suicidality \& very severe depressive symptomatology (BDI-II Score \> 40)