Fig. 3

Training and transfer task performance (per-protocol set). A Training improvement in the letter updating task. B Training improvement in the Markov decision-making task. No enhanced training gains were observed after anodal stimulation compared to sham stimulation. C Enhanced performance in the N-back task after anodal stimulation compared to sham stimulation. D Transfer task performance in the WMT. E Transfer task performance in the VLMT. There were no differences in WMT or VLMT between anodal and sham groups. Pre, pre-assessment. T3, T6, T9, training days 3, 6, 9. Dots represent mean values and shaded areas indicate 95% confidence intervals. tDCS, transcranial direct current stimulation. FU, 1-month follow-up. FUII, 7-months follow-up. WMT, Wiener Matrices Test. VLMT, verbal learning and memory test