Results of the 2 Hz signals. (A) Grand average FFT-amplitude spectra derived from EEG signals at each participant’s best four-electrode cluster for the 2 Hz signal for the different experimental conditions (blue: neutral;green: pleasant; red: unpleasant). The shaded areas around the means indicate 95% confidence intervals. The electrode cluster selected for the analysis is highlighted in the topography. (B) Amplitude values of the 2 Hz signals for each participant (single dots) and experimental condition. Mean amplitude values are marked by horizontal black lines and 95% Bayesian highest density interval (HDI) represented as white boxes. **:p < .01; n.s.: not significant.