Dowling, W.J., Hollombe, A.W. (1977). The perception of melodies distorted by splitting into several octaves: Effects of increasing proximity and melodic contour. Percept. Psychophys. 21, 60-64

Splitting up the familiar tune "Yankee Doodle" by placing successive notes in different octaves makes it very difficult to recognize. The present experiments generalize this finding to more than one familiar tune and to presentation by actual musical instruments. Tunes differ in the degree to which their recognizability is affected by scrambling into different octaves, but recognition of all 10 tunes investigated was substantially diminished by the distortion. Increasing pitch proximity of temporally adjacent notes by leaving pairs or triples of successive notes intact within the same octave increases recognizability of at least some scrambled tunes. Leaving the melodic contour (the pattern of ups and downs) intact while splitting up the melody increases recognizability for subjects informed of the preservation of contour, though recognition is still worse than for undistorted versions.