At first, the tones (1 sec long) oc

At first, the tones (1 sec long) occurred about every 5 sec, with high probability of C (0.4). Eventually, they occurred with uniform probability every 1.4 sec. To head off the artifact collectors, I must point out that knowledge of the lowest and highest tones was a superfluous cue. The "chroma" dimension so overwhelmingly overrode the high-low dimension that most of the tasks, with practice, became very easy. In any case, these spurious cues occurred only in the training tapes--not in the final piano note tests.