Human-Centered Harmonic Analysis of the Beatles’ Yesterday: Chord Wheel, Process Diagrams, and Eye-Tracking Insights

Abstract: This paper presents an innovative approach to analyzing the harmony of the well-known and iconic song Yesterday by the Beatles using the chord wheel diagram in combination with BPMN-based process modeling. While classical methods of harmonic explanation rely on standard notation (including tablature) and chord symbols, our method focuses on visual and procedural representations. According to our findings, these representations reduce cognitive load and thereby improve understanding of music. They are, however, primarily intended for amateur musicians rather than trained professionals.The chord wheel diagram developed by our team provides an interactive visualization of tonal relationships, enabling users to follow the sequence of chord formation within a key, while also explaining chord progressions and their structural logic. Based on this, process diagrams modeled in BPMN formalize the sequential logic of harmonic development and its direct connection to the song’s melody. This dual representation—circular tonal mapping and algorithmic procedural modeling—offers students an accessible way to understand why the harmonic structure of Yesterday creates its characteristic expressive quality.To evaluate the usability and clarity of this approach, we conducted a qualitative study supported by eye-tracking experiments. Eye movement data revealed which parts of the diagrams were more difficult for participants to comprehend, highlighting critical points of cognitive overload. Based on this analysis, we define how process models can be refined to guide attention more effectively, reduce ambiguity, and improve the integration of harmonic and melodic information.Our findings suggest that this combination of chord wheel visualization, BPMN process modeling, and eye-tracking–driven analysis provides unique insights into how non-professional musicians interact with harmonic structures. Compared with conventional notation, participants perceived visual and process-based models as more intuitive, especially when applied to familiar repertoire such as Yesterday.We argue that integrating computational models with human-centered visualization and empirical usability testing represents a promising alternative for music education and harmonic analysis. By applying principles of human–computer interaction to music theory, this study shows how modern computer science technologies can support creativity, learning, and meaningful interaction in music.

Keywords: Chord Wheel Diagram, Harmonic Analysis, Business Process Modelling Notation, BPMN, Eye-tracking, Music Visualization, Human Computer Interaction, Chord Wheel Diagram

DOI: 10.54941/ahfe1007097

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