Vocal Production Mechanisms in Vertebrates: Modeling the Voice

Prof. Tecumseh Fitch

Oct. 4, 2010, 3 p.m. HF 136

Vocal production in vertebrates (animals with a spine, including frogs, alligators, birds and mammals) is based upon a two-component system of source (air generated by vibrating tissue) and filter (via resonances of air contained in the vocal tract). I will describe advances in our understanding of vertebrate communication made possible by a recent focus on the physics and physiology of the filter component; while this component was once thought to be used by humans almost exclusively, it is now
clear that it plays an important role in vocal communication in many species.

The physical basis of vocal tract filtering is rather simple; far more challenging in the coming years will be an understanding of the voice source. Most research till now has focused on the human larynx (more generally, the mammalian vocal folds), but the source in birds is quite different: vibrating membranes within the syrinx (a specialized organ possessed only by birds). We hope to combine anatomical measurements, physiological observations and computational models to understand the great range of variation in the avian syrinx, and so to isolate the main determinants of acoustic variability in bird songs.