Clinical trial NCT03518749: Effects of tDCS-enhanced Cognitive Control Training on Depression
Official title: Effects of tDCS-enhanced Cognitive Control Training on Depression
Study type: INTERVENTIONAL
Overall status: UNKNOWN
Phase: NA
Conditions: Depression Unipolar
Keywords: Depression
transcranial direct current stimulation (tDCS)
Lead sponsor: University Hospital Tuebingen
Sponsor class: OTHER
Collaborators: name: German Federal Ministry of Education and Research
name: Universität Tübingen
First posted: 2018-05-08
Enrollment: 57
Sex: ALL
Minimum age (years): 18
Maximum age (years): 65
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: BASIC_SCIENCE

Brief summary: Deficient cognitive control (CC) is one of the central characteristics of major depression (MD). Hypoactivation of the dorsolateral prefrontal cortex (dlPFC) has been linked with this deficit. Antidepressants and cognitive-behavioral therapies modify CC most-likely as a common mechanism of treatment. Transcranial direct current stimulation (tDCS) is a safe, simple and effective non-invasive method to modulate the cortical excitability. It has been shown, that the activity of the dlPFC can be modulated by transcranial direct current stimulation (tDCS) with polarity-dependent learning-phase specific effects on performance that, when combined with training, can outlast the stimulation.

The goal of this randomized, sham-controlled, rater blind clinical trial is to investigate the effect of a tDCS-enhanced CC Training (CCT) on depressive symptom severity and compare the stimulation intensities 1mA, 2mA and sham tDCS. Overall, the study will include 57 participants (n = 19 per group). Each participant will complete 12 training sessions with online sham/ anodal tDCS.

As a training task we will use an adaptive version of the paced auditory serial addition task (PASAT). In the PASAT, digits are presented auditive and participants have to add the current digit to the digit they heard before. In the adaptive version the interstimulus-intervals decrease (increase) when four consecutive trials are correct (incorrect). The PASAT is known to elicit frustration. Participants have to exert cognitive control over these emotions to complete the task successfully.

Before, during and after the training symptom severity will be assessed. Baseline and post-training performance in the PASAT and in a transfer task (delayed working memory task, DWM) will be measured.

To further explore variables that influence the effect of tDCS on depressive symptom severity we will measure brain activity (EEG, NIRS), heart rate, global functioning (GAF), emotion regulation strategies, self-esteem, mood ratings and subjective performance ratings before and after the training and collect genetic factors.

Sustainability of the training effects will be measured at a follow-up visit (3 months later).


Eligibility criteria: Inclusion Criteria:

* current Major Depressive Episode
* right handedness

Exclusion Criteria:

* history of seizures
* Intracranial implants (e.g. aneurysm clips, shunts, stimulators, cochlear implants, or electrodes) or any other metal object within or near the head, excluding the mouth, that cannot be safely removed
* pregnancy
* use of mood stabilizers
* diagnosed bipolar disorder
* current substance abuse (nicotine excluded)
* current substance addiction (nicotine excluded)
* diagnosed psychotic diseases
* diagnosed anorexia nervosa
* diagnosed personality disorders: cluster A, antisocial personality disorder,
* borderline personality disorder

Primary outcomes:
measure: Change of MADRS scores
timeFrame: Assessment one week before training start (week -1, day -5 on average) and in the last training session (week 4, day 26)
Secondary outcomes:
measure: BDI scores
timeFrame: Assessment one week before training start (week -1, day -5 on average), in the post training session (week 5, day 31 on average) and at follow-up (week 17, day 110 on average)
measure: Number of correct trials in the PASAT
timeFrame: Assessment one week before training start (week -1, day -5 on average), in the post training session (week 5, day 31 on average) and at follow-up (week 17, day 110 on average)
measure: RT in the DWM
timeFrame: Assessment one week before training start (week -1, day -5 on average), in the post training session (week 5, day 31 on average) and at follow-up (week 17, day 110 on average)
measure: Number of correct trials in the DWM
timeFrame: Assessment one week before training start (week -1, day -5 on average), in the post training session (week 5, day 31 on average) and at follow-up (week 17, day 110 on average)
measure: GAF score
timeFrame: Assessment one week before training start (week -1, day -5 on average) and in the post training session (week 5, day 31 on average)
measure: Delta Mood ratings
timeFrame: Assessment one week before training start (week -1, day -5 on average), in the post training session (week 5, day 31 on average) and at follow-up (week 17, day 110 on average)
measure: Subjective performance ratings
timeFrame: Assessment one week before training start (week -1, day -5 on average), in the post training session (week 5, day 31 on average) and at follow-up (week 17, day 110 on average)
measure: Electroencephalography (EEG) measures
timeFrame: Assessment one week before training start (week -1, day -5 on average) and in the post training session (week 5, day 31 on average)
measure: Prefrontal Brain activity (NIRS)
timeFrame: Assessment one week before training start (week -1, day -5 on average) and in the post training session (week 5, day 31 on average)
measure: Course of MADRS scores
timeFrame: Assessment once a week during training (week 1, 2 and 3 at day 5, 12 and 19 respectively on average) and at the follow up visits (week 5 and 17, day 31 and 110 on average)
measure: Prefrontal Brain activity (NIRS) as a predictor
timeFrame: Assessment one week before training start (week -1, day -5 on average)
measure: Electroencephalography (EEG) measures as a predictor
timeFrame: Assessment one week before training start (week -1, day -5 on average)
measure: Genetic factors as predictors
timeFrame: Assessment one week before training start (week -1, day -5 on average)
Other outcomes:
Locations:
city: Tubingen
country: Germany
facility: University Hospital Tuebingen
state: Baden-Württemberg
Study officials:
References:
citation: Sommer A, Fallgatter AJ, Plewnia C. Investigating mechanisms of cognitive control training: neural signatures of PASAT performance in depressed patients. J Neural Transm (Vienna). 2022 Jun;129(5-6):649-659. doi: 10.1007/s00702-021-02444-7. Epub 2021 Nov 23.