Performance is measured as percent correct. The tones used in this experiment were created as pure tones ranging from 220 Hz to 880 Hz. There are 25 tones in all, equally spaced across the interval. Test tone selection is constrained to be either the same as the target tone or different by two semitones. Thus the same 12-tone set is used when choosing a target tone but the choice is not random.
Selection is random with the constraint that no tone can repeat as a distracter on any one trial.
Thus five unique distracters are presented between the target and test tones. In order to distinguish target and test tones, there is a sec delay between the test tone and the start of the 5-tone distracter sequence. The test tone appears sec after the end of the 5-tone distracter sequence. When target and test tones are different, they can form an ascending or descending series with equal probability. Return to Top Requirements Because the stimuli in this experiment are auditory, the computer used to present the experiment must have a sound card.