Cognitive Control Training for Remitted Depressed Patients

Study Overview
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Brief Summary
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The purpose of this study is to explore the effectiveness of an internet-delivered cognitive control training as a preventive intervention for remitted depressed patients.

Detailed Description
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Prospective studies have linked impaired cognitive control to increased cognitive vulnerability for future depression. Importantly, experimental studies indicate that cognitive control training can be used to reduce rumination and depressive symptomatology in MDD samples. Furthermore, studies exploring the potential of cognitive control training in at-risk undergraduate students indicate that cognitive control training has beneficial effects on rumination, an important vulnerability factor for depression. Provided that remitted depressed patients form a high-risk group for developing future depressive episodes, the current study will explore whether internet-delivered cognitive control training can be used to reduce vulnerability for future depression in remitted depressed patients. The investigators will explore effects on depressive symptomatology, (mal-)adaptive emotion regulation (directly following training and at 3 months follow-up), and indices of functioning (at 3 months follow-up).

Official Title
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Cognitive Control Training as a Preventive Intervention for Depression: A Double-blind Randomized Controlled Trial Study

Conditions
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Major Depression in Remission

Intervention / Treatment
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* Behavioral: Cognitive Control Training
* Behavioral: Low Cognitive Load Training


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: History of ≥ 1 depressive episode(s) Currently in stable full or partial remission (≥ 6 months) Exclusion Criteria: Major depressive disorder (MDD; current) Bipolar disorder (current and/or previous) Psychotic disorder (current and/or previous) Neurological impairments (current and/or previous) Excessive substance abuse (current and/or previous) No other comorbid disorders (current) No ongoing psychotherapeutic treatment (maintenance treatment is allowed, but with a frequency less than once / 3 weeks) Use of antidepressant medication is allowed if kept at a constant level

Ages Eligible for Study
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Minimum Age: 23 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: cognitive control training<br>internet-delivered, 2 weeks | Behavioral: Cognitive Control Training<br>* 10 adaptive Paced Auditory Serial Addition Task (PASAT) sessions, 400 trials each<br>|
| Active Comparator: low cognitive load training<br>internet-delivered, 2 weeks | Behavioral: Low Cognitive Load Training<br>* 10 low cognitive load sessions, 400 trials each<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in depressive rumination from baseline to the post-training assessment and follow-up (RRS) | Assessed using the Ruminative Response Scale (RRS) | baseline, 2 weeks, 3 months | 
| Change in depressive symptomatology from baseline to the post-training assessment and follow-up (BDI-II) | Assessed using the Beck Depression Inventory (BDI-II) | baseline, 2 weeks, 3 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| (mal-)Adaptive cognitive emotion regulation (CERQ) | Assessed using the Cognitive Emotion Regulation Questionnaire (CERQ) | baseline, 2 weeks, 3 months | 
| Quality of Life (QLDS) | Assessed using the Quality of Life in Depression Scale (QLDS) | baseline, 3 months | 
| Disability (WHODAS 2.0) | Assessed using the World Health Organization Disability Assessment Schedule 2.0 (WHODAS 2.0) | baseline, 3 months | 
| Resilience (RS) | Assessed using the Resilience Scale (RS) | baseline, 3 months | 
| Remission from depression (RDQ) | Assessed using the Remission of Depression Questionnaire (RDQ) | baseline, 3 months |