Remembering the melody and timbre, forgetting the key and tempo

The identity of a melody is independent of surface features such as key (pitch level), tempo (speed), and timbre (musical instrument). We examined the duration of memory for melodies (tunes) and whether such memory is affected by changes in key, tempo, or timbre. After listening to previously unfamiliar melodies twice, participants provided recognition ratings for the same (old) melodies as well as for an equal number of new melodies. The delay between initial exposure and test was 10 min, 1 day, or 1 week. In Experiment 1, half of the old melodies were transposed by six semitones or shifted in tempo by 64 beats per minute. In Experiment 2, half of the old melodies were changed in timbre (piano to saxophone, or vice versa). In both experiments, listeners remembered the melodies, and there was no forgetting over the course of a week. Changing the key or tempo from exposure to test had a detrimental impact on recognition after 10 min and 1 day, but not after 1 week. Changing the timbre affected recognition negatively after all three delays. Mental representations of unfamiliar melodies appear to be consolidated after only two presentations. These representations include surface information unrelated to a melody's identity, although information about key and tempo fades at a faster rate than information about timbre.