“…The recorded EEG data were analyzed offline using the MATLAB software (version 2016a, MathWorks, Inc., MA, United States). Among the 31 channels, the following 9 channels were selected for the analysis to be comparable with the previous results ( Ma et al, 2014b ; Fudali-Czyż et al, 2016 ): F3, Fz, F4, C3, Cz, C4, P3, Pz, and P4. Although other fronto-central (FC9, FC5, FC1, FC2, FC6, and FC10) and centro-parietal (CP5, CP1, CP2, and CP6) channels were additionally analyzed in the previous studies, we did not include them in the analysis because our EEG system did not provide midline channels needed to compare the results.…”