Dynamics of tonality.

Abstract

As listeners of western tonal music, we establish mental representations of tonal space: the distance relationships between major and minor keys (tonal centers). Evidence for the distance relationships underlying tonal space derives from music theory, cognitive psychology, and statistical learning approaches. Tonal space is represented parsimoniously on the surface of a torus. Although the torus itself is a static structure, the movements of music about its surface are shaped by the nuances of melodies and harmonic progressions that mold the sense of the tonal center through time. Central to an understanding how our brains interact with music's dynamic movements in tonal space, and the main aspect of this presentation, is a consideration of the timescale(s) over which the movements are modeled. At long timescales, movements on the toroidal surface are slow and perhaps tend to reflect symbolic music‐theoretic descriptions in which a series of stable tonal centers is established. When biased toward shorter timescales the toroidal dynamics reveal much livelier movement that depends on the tonal content of individual chords. Intermediate timescales reveal tonal dynamics between these two extremes, both stability and rapid transitions, and perhaps reflect the scale that most closely match our sense of tonal movement.