Notating disfluencies and temporal deviations in music and arrhythmia

Abstract

Expressive music performance and cardiac arrhythmia can be viewed as deformations of, or deviations from, an underlying pulse stream. I propose that the results of these pulse displacements can be treated as actual rhythms and represented accurately via a literal application of common music notation, which encodes proportional relations among duration categories, and figural and metric groupings. I apply the theory to recorded music containing extreme timing deviations and to electrocardiographic (ECG) recordings of cardiac arrhythmias. The rhythm transcriptions are based on rigorous computer-assisted quantitative measurements of onset timings and durations. The root-mean-square error ranges for the rhythm transcriptions were (19.1, 87.4) ms for the music samples and (24.8, 53.0) ms for the arrhythmia examples. For the performed music, the representation makes concrete the gap between the score and performance. For the arrhythmia ECGs, the transcriptions show rhythmic patterns evolving through time, progressions which are obscured by predominant individual beat morphology-and frequency-based representations. To make tangible the similarities between cardiac and music rhythms, I match the heart rhythms to music with similar rhythms to form assemblage pieces. The use of music notation leads to representations that enable formal comparisons and automated as well as human-readable analysis of the time structures of performed music and of arrhythmia ECG sequences beyond what is currently possible.

COSMOS: Computational Shaping and Modeling of Musical Structures

“…In a reversal of convention, turning performance into writing, in “Practicing Haydn” (Chew, Child, Grønli 2013, vimeo.com/109998951 ), my sight-reading is transcribed into a performable score, complete with starts and stops, repetitions, and corrections, revealing the cognitive process of constructing a performance. Taking this idea further, free rhythms in performance are transcribed for close examination and cross-comparison in Chew ( 2018 ).…”

“…Notational technology evolved over the centuries to allow performers to replicate music note sequences faithfully (Kelly, 2014 ). Traditional music notation was used to accurately transcribe the extreme rhythms of music performance in Chew ( 2018 ). The difference between what the composer wrote (the abstract idea) and what the performer did (the actual experience for the listener) was made all the more stark by the use of the same notational technology.…”

“…Chew et al ( 2021 ) added to this a possible arrhythmia-based inspiration for the opening motif of Beethoven's Fifth Symphony. Chew ( 2018 ) used music notation to represent the rhythms of atrial fibrillation, employing mixed meters and metric modulations to accurately capture the high rhythmic variations. This method has been used to compose pieces in the Arrhythmia Suite (Chew, 2021 )—see excerpt and corresponding ECG in Figure 2 .…”

“…Performances and music-like sequences such as cardiac signals form an untapped source for music structure analysis (Chew, 2017 , 2018 ) in music information research and research in music perception and cognition. This theme focuses on extracting and representing the experienced music structures in recorded performances and arrhythmic cardiac signals.…”

Mapping Inter-Cardiovascular Time-Frequency Coherence to Harmonic Tension in Sonification of Ensemble Interaction Between a Covid-19 Patient and the Medical Team

“…However, no significant effects were identified. Overall, accuracy measures ranged from 53.66% (stimulus pair P-JH using cello 17 ) to 80.49% (stimulus pair P-HR using glockenspiel 18 ).…”