Effects of tDCS on Cognitive Control and Emotion Regulation in Depressed Patients

Deficient cognitive control (CC) and the use of dysfunctional emotion regulation strategies (ERS) are both central characteristics of major depression. Both are associated with reduced activity of the dorsolateral prefrontal cortex (dlPFC). Transcranial direct current stimulation (tDCS) is a safe, simple and effective non-invasive method to modulate the cortical excitability. The goal of this randomized, sham-controlled, double blind clinical trial is to examine the effect of transcranial direct current stimulation (tDCS) on the CC and ERS in depressed patients compared to healthy subjects. Overall, the study will include 44 participants (22 depressed Patients and 22 healthy subjects). Each participant will complete a CC task while receiving sham tDCS in one session and anodal tDCS in the other session (counterbalanced). Afterwards the ERS 'rumination' will be measured during a resting phase by means of a questionnaire and psychophysiological measures (heart rate variability). The investigators hypothesize (a) an amelioration of CC by anodal tDCS and (b) a reduced use of the dysfunctional emotion regulation strategy 'rumination' after anodal tDCS. Overall this experiment will provide new and reliable data for the development of new treatment methods.