Categorical Tonality Perception Modulates Crossmodal Correspondences between Musical Chords and Colors

Abstract

What is the role of categories in crossmodal correspondence? We tested this question by examining whether the properties of tonality-color crossmodal correspondence differ depending on the degree of categorical perception of musical chords within individuals rather than on their physical properties. The experiment used morphed chords of pure tones graded from minor to major. Participants, who were classified as either categorizers or non-categorizers using chord tonality identification and discrimination tasks, selected a color that they thought matched each chord. The results showed that only categorizers selected similar colors for within-category chord pairs and dissimilar colors for between-category chord pairs. They also demonstrated a wider range of color choices and temporally consistent mapping. In crossmodal mappings, categories may clarify the relationship between features in a sensory space, and this relationship is reflected in other associated sensory features, leading to the exaggeration and stabilization of crossmodal correspondences.

Keywords: crossmodal correspondence, sound-color crossmodal correspondence, categorical perception, tonality, isomorphism