Vocal similarity predicts the relative attraction of musical chords

Significance The foundations of human music have long puzzled philosophers, mathematicians, psychologists, and neuroscientists. Although virtually all cultures uses combinations of tones as a basis for musical expression, why humans favor some tone combinations over others has been debated for millennia. Here we show that our attraction to specific tone combinations played simultaneously (chords) is predicted by their spectral similarity to voiced speech sounds. This connection between auditory aesthetics and a primary characteristic of vocalization adds to other evidence that tonal preferences arise from the biological advantages of social communication mediated by speech and language. Musical chords are combinations of two or more tones played together. While many different chords are used in music, some are heard as more attractive (consonant) than others. We have previously suggested that, for reasons of biological advantage, human tonal preferences can be understood in terms of the spectral similarity of tone combinations to harmonic human vocalizations. Using the chromatic scale, we tested this theory further by assessing the perceived consonance of all possible dyads, triads, and tetrads within a single octave. Our results show that the consonance of chords is predicted by their relative similarity to voiced speech sounds. These observations support the hypothesis that the relative attraction of musical tone combinations is due, at least in part, to the biological advantages that accrue from recognizing and responding to conspecific vocal stimuli.