Changes of the alpha power after the end of acoustic stimulation. Time course of the mean alpha (8–13 Hz) power of the auditory BESA source activity during (averaged over the whole stimulation period, red) and after the end (black) of acoustic CR neuromodulation (A), the noisy CR-like stimulation (E) and the LFR stimulation (I) expressed as a percentage change from the baseline activity. Significant changes are marked with the horizontal black line (A, E, I). Format as in Fig. 4. Power spectra for the alpha frequency range at baseline and for the time period 60–120 s (inside the red window in A, E, I) after end of the acoustic CR neuromodulation (C), the noisy CR-like stimulation (G) and the LFR stimulation (K). The effect of acoustic CR neuromodulation (B, D), the noisy CR-like stimulation (F, H) and the LFR stimulation (J, L) on the mean current source density analyzed by sLORETA (format as in Fig. 4). The strongest increase compared to baseline (indicated by red voxels) was localized in the left and right transverse temporal gyrus after acoustic CR neuromodulation (xyz − 40, − 29, 9; BA 41).