The EEG recordings are referenced to the average of TP9 and TP10 channels (digitally linked mastoids reference). They are preprocessed with a modified version of the adaptive artifact subtraction (AAS) algorithm for off-line correction of imaging artifact [Gonçalves et al., 2007], downsampled to 1 kHz and filtered between 0.5 and 40 Hz, and finally subjected to the attenuation of ballistocardiographic and ocular artifacts [Mantini et al., 2007a].
