Fig. 4From: Discrete classification technique applied to TV advertisements liking recognition system based on low-cost EEG headsetsResults of the PSD extraction processing for each band. In the abscissa axis is shown de power of the signal per Hz in dB/Hz. In the ordinate axis, frequencies are shown in Hz. a PSD for alpha channel (3–7 Hz), b PSD for beta channel (8–13 Hz), c PSD for gamma channel (14–29 Hz) d PSD for theta channel (30–47 Hz)Back to article page