# Chaos in human phonation and its measurement

> **NIH NIH R01** · UNIVERSITY OF WISCONSIN-MADISON · 2020 · $325,125

## Abstract

PROJECT SUMMARY
 Voice disorders caused by physical injury, voice misuse, physiological disease, and surgery represent a
significant social cost, resulting in severe functional and psychological limitations on the lives of millions of
Americans. Acoustic analysis represents a promising tool for clinical assessment of voice disorders; however, it
has not been widely applied outside of research despite its low cost, objectivity, and non-invasive nature. The
intrinsic complexity of voice production and aperiodicity of disordered voice necessitates that acoustic analysis
be nonlinear. Current nonlinear parameters are capable of quantifying both normal and disordered phonation;
however, existing nonlinear methods fail to comprehensively describe the non-stationary, dynamic elements
comprising voice signals. The long-term goal of the proposed research is to expand the utility of nonlinear
dynamic analysis in clinical practice as an objective means for detecting vocal dysfunction and monitoring voice
rehabilitation following treatment intervention.
 In Aim 1, excised larynx models will be employed to simulate and investigate physiological conditions
contributing to breathy and rough phonation, including extreme subglottal pressures, vocal fold elongation,
asymmetrical tension, and benign mass lesions. Diffusive chaos and intrinsic dimension nonlinear analysis will
be implemented to evaluate the four different type components present in the corresponding acoustical output
and to subsequently construct voice type component profiles (VTCP). Quantitatively describing the VTCP will
provide more descriptive information pertaining to the physiological location and conditions underlying
pathological phonation. Aim 2 will focus on applying VTCP nonlinear analysis to normal and disordered patients
in a variety of voice tasks, such as vowel and consonant utterances and connected speech, and assessment of
clinical treatment interventions, including surgical treatment of benign mass lesions and vocal fold paralysis and
rehabilitative voice training for esophageal and tracheoesophageal speech. To facilitate wider and more
extensive utility of nonlinear dynamic analyses, we will assess the concurrent validity of the VTCPs with the
clinically established technique of auditory-perceptual assessment of voice quality. The likely impact of this
research is that innovative methods of diffusive chaos and intrinsic dimension nonlinear analysis will provide
significant improvements over previous acoustical parameters in both computationally efficiency and voice
quality description. Moreover, acoustical analysis of disordered phonation in excised larynges will provide a
physical model to examine the physiological and biomechanical conditions underlying pathologic voice
production, which remains poorly understood. Lastly, the clinical utility of VTCP analysis as a diagnostic tool for
voice disorder detection will be demonstrated.

## Key facts

- **NIH application ID:** 9891044
- **Project number:** 5R01DC006019-12
- **Recipient organization:** UNIVERSITY OF WISCONSIN-MADISON
- **Principal Investigator:** Jack J Jiang
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2020
- **Award amount:** $325,125
- **Award type:** 5
- **Project period:** 2003-06-01 → 2024-04-30

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/9891044

## Citation

> US National Institutes of Health, RePORTER application 9891044, Chaos in human phonation and its measurement (5R01DC006019-12). Retrieved via AI Analytics 2026-05-23 from https://api.ai-analytics.org/grant/nih/9891044. Licensed CC0.

---

*[NIH grants dataset](/datasets/nih-grants) · CC0 1.0*