Dynamic System Coupling in Voice Production

Area of Science:

• Bioacoustics
• Biophysics
• Speech Science

Background:

• Voice production is crucial for communication across many vertebrate species.
• Existing theories, MyoElastic-AeroDynamic (MEAD) and Source-Filter Theory (SFT), offer distinct perspectives on voice production.
• MEAD focuses on vocal fold dynamics, while SFT addresses acoustic filtering through the vocal tract.

Purpose of the Study:

• To review and integrate the MEAD and SFT for a holistic understanding of voice production.
• To explore the nonlinear extension of SFT and its parallels with musical instrument acoustics.
• To discuss the application of these integrated theories to human and animal vocalization.

Main Methods:

• Comprehensive literature review of MEAD and SFT.
• Analysis of nonlinear dynamics in voice production.
• Comparative study of vocalization across species.

Main Results:

• MEAD and SFT are complementary, not mutually exclusive, aspects of voice production.
• A nonlinear extension of SFT reveals similarities to sound production in brass instruments.
• A systems-level perspective, viewing voice production as a dynamically coupled system, is supported by nonlinear dynamics.

Conclusions:

• A unified theory integrating MEAD and SFT provides a more complete model of voice production.
• Nonlinear dynamics offer valuable insights into the complex mechanisms of vocalization.
• Viewing voice production as a coupled system enhances our understanding of both human and animal communication.