Expectations for melodic contours transcend pitch

Abstract

The question of what makes a good melody has interested composers, music theorists, and psychologists alike. Many of the observed principles of good "melodic continuation" involve melodic contour-the pattern of rising and falling pitch within a sequence. Previous work has shown that contour perception can extend beyond pitch to other auditory dimensions, such as brightness and loudness. Here, we show that the generalization of contour perception to nontraditional dimensions also extends to melodic expectations. In the first experiment, subjective ratings for 3-tone sequences that vary in brightness or loudness conformed to the same general contour-based expectations as pitch sequences. In the second experiment, we modified the sequence of melody presentation such that melodies with the same beginning were blocked together. This change produced substantively different results, but the patterns of ratings remained similar across the 3 auditory dimensions. Taken together, these results suggest that (a) certain well-known principles of melodic expectation (such as the expectation for a reversal following a skip) are dependent on long-term context, and (b) these expectations are not unique to the dimension of pitch and may instead reflect more general principles of perceptual organization.

Figure 1

Simplified representations of a complex tone (left), increasing in pitch (top right), brightness (middle right), or loudness (bottom right).

Figure 2

(A) Visual representation of the scales used for F0 (for pitch melodies), spectral center (for brightness melodies), and level (for loudness melodies). Each scale contains 27 steps; the values of the 1st, 2nd, 13th, and 27th steps are given as examples. (B) Schematic diagram of an example melody, where horizontal lines represent individual tones in the melody.

Figure 3

From Experiment 1, listener ratings of continuation for three-tone sequences in pitch (top), brightness (center), and loudness (bottom). Columns correspond to the three predictors (Proximity, Inertia, and Post-skip Reversal). Vertical dashed lines mark important values of the Proximity predictor. Mean ratings from all subjects are plotted in black with error bars +/− one standard error (between subjects). Dotted lines show mean ratings from the 4 subjects with 12 or more years of musical training. Thin solid lines show mean ratings from the 5 subjects with 1 or fewer years of musical training.

Figure 4

Summed absolute point-to-point differences in ratings along the Proximity curve as a function of years of musical experience. Least-squares lines are plotted for all three dimensions along with correlation coefficients (r). The asterisk (*) indicates a significant correlation at p < 0.05.

Figure 5

From Experiment 2, listener ratings of continuation for three-tone sequences in pitch (top), brightness (center), and loudness (bottom). Columns correspond to the three predictors (Proximity, Inertia, and Post-skip Reversal). Vertical dashed lines mark important values of the Proximity predictor. Mean ratings from all subjects are plotted in black with error bars +/− one standard error (between subjects). Dotted lines show mean ratings from the 5 subjects with 8 or more years of musical training. Thin solid lines show mean ratings from the 5 subjects with 0 years of musical training.