Fig. 5: Methods overview.

Illustrated is a visual summary of all methods and analyses applied in the current study. The top part depicts the timeline of an experimental session, showing the sequence and duration of key interventions. The horizontal axis marks time in minutes. Each session began with administering either a dose of MPH or a placebo, depending on the participants’ subgroup. Before starting the experimental task and EEG recording, participants received active/real tDCS on one appointment, and sham tDCS on the other (for details see methods section). Behavioral and neurophysiological data collection started 120 min post MPH/placebo administration and lasted approximately 15 min for the task reported in this study. Of note, this was followed by another task (duration ~20 min) that is not reported here. All details are provided in the methods section. The bottom part summarizes the analyses applied from the sensor to the source level. Abbreviations: tDCS (transcranial direct current stimulation), MPH (methylphenidate).