Inference of mode in melodies

Abstract

The listener's ability to infer the mode (major vs. minor) of a piece of Western tonal music was examined. Twenty-four subjects, divided into two groups according to their level of musical expertise, evaluated 11 musical stimuli, selected from J.S. Bach's Well-Tempered Clavier (WTC). The stimuli included both unambigous and ambiguous examples of the two modes, as well as one example of a modulation (from minor into major). The stimuli consisted of unaccompanied melodic openings of compositions, each containing 10 tones. Stimulus presentation and evaluation took place in nine progressively longer steps, starting with presentation of the first two tones, followed by its evaluation on a continuous scale, with 0="extremely minor" and 100="extremely major", and ending with evaluation of the complete stimulus. The results showed that mode inference followed the prescribed modes and tended to become more definite with increasing stimulus length. Experts were generally more definite in their inferences than non-experts. Surprisingly, the temporal structure of stimuli also appeared to affect mode inference. The degree of definiteness of mode judgements did not systematically differ between the two modes. It was concluded that listeners are able to infer the mode of a piece of music in the absence of explicit harmonic cues. The generalizability of the results with respect to music pieces of late periods in Western music history, as well as the impact of different musical genres on mode inference were discussed.