Fig. 2.

Structure of a single block of the experiment. The subject received an auditory cue, instructing them to respond to auditory tones or control the tones (by pressing a button). After 2s, a series of tones was presented. Deviant tones (red striped circles) differed in frequency from the preceding tone. Whether a tone was a standard or deviant was independent of whether the tone was triggered by the computer or the subject. The block ended with an inter-block interval of 1s. Image credits: Press button by Hea Poh Lin and Speaker by ProSymbols from the Noun Project, CC BY 3.0.