From Bach to Pélog: Harmonic Dissonance Feels Rough on Sandpaper in an Auditory-Tactile Matching Task

Dissonant stimuli or stimuli with high auditory roughness are often related to jagged shapes, while consonant stimuli or those with low auditory roughness are associated with curvy and smooth shapes. This empirical study explores auditory-tactile associations for roughness in diverse musical excerpts. We investigate whether auditory harmonic dissonance is perceptually associated with tactile roughness in sandpapers with varying grit values, and whether emotional dimensions mediate this cross-modal relationship. Participants were asked to listen to excerpts from several musical styles, accounting for possible effects of familiarity including Bach-style chorales, golden-era jazz, random, and non-Western polyphonic Indonesian styles (i.e., sléndro and pélog), and match them with sandpapers of different roughness. Western listeners matched the most dissonant and the least familiar harmonic organizations with rougher sandpapers. Other parameters such as note density and dissimilarity to 12-tone equal temperament contributed slightly to that relationship. Rough sandpapers and dissonant harmonizations share similar affective profiles (i.e., high arousal and negative valence), suggesting an emotional connection in the cross-modal association.