Influence of tonal fusion and sensory dissonance on scale evolution

Determine how the psychoacoustic phenomena of tonal fusion and sensory dissonance influence the cultural evolution of musical scales across societies, including whether and how these mechanisms contribute to scale selection and prevalence of specific intervals.

Background

Harmonic theories of scale evolution are often grounded in psychoacoustic mechanisms including tonal fusion and sensory dissonance. While these phenomena have robust empirical support and are linked to consonance perception, their role in shaping the evolution of scales has not been conclusively established.

The paper compares harmony-based models with melody-based and complexity-based models across 1,314 scales from 96 countries, showing that harmony models cannot explain step-size distributions but do predict certain interval prevalence when combined with melody models. Despite these findings, a direct mechanistic account of how tonal fusion and sensory dissonance drive scale evolution remains unresolved.