Colloquium: Still breathing? The state of aerodynamics in phonetics and phonology

May 21, 3:30-5pm, Cobb 201
Ryan Shosted, University of Illinois at Urbana-Champaign

In this talk, I will discuss the current prospectus for incorporating aerodynamic models of speech production into problems of sound patterns and sound change, more than thirty years after the possibility was first introduced in the linguistics community (cf. Ohala 1975). Several questions are relevant: Do aerodynamic features play a significant role in phonology? Is there evidence for aerodynamic targets? If so, how are they different from articulatory targets? What can we expect to gain from collecting aerodynamic signals (i.e. pressure and flow) when describing and documenting sound patterns?

Many unanswered questions in phonetics and phonology have to do with the relationship between physiological production, acoustics, and perception. While great strides have been made in understanding the relationship between acoustics and perception, significantly less is known about the relationship between the physiological production of speech and its acoustic output. Of all underlying production mechanisms, the relationship between aerodynamics and acoustics is perhaps the least understood. There may be practical reasons for this, including limited access to the appropriate technology and the sometimes daunting mathematics involved in fluid dynamics equations. However, even with the relative accessibility of instruments like the Rothenberg mask (Rothenberg 1973) and data acquisition systems designed to support this kind of research, comparatively little systematic work has been done to document and model the aerodynamics of speech. Complete aerodynamic descriptions of even relatively common speech sounds (like fricatives) are scarce and continue to inhabit the clinical literature more comfortably than the linguistic. As Shadle (1999) has noted, “[A]erodynamics underlies all aspects of speech production”. In this talk, I will argue that aerodynamic investigations can provide key insights into the development, maintenance, and transformation of sound patterns in human language.

To this end, I will discuss three experiments in progress that deal crucially with speech aerodynamic questions or methodologies: (1) the synchronic relationship between vowel height and nasalization; (2) the diachronic relationship between ejective and implosive consonants; and (3) the diachronic origins of the whistled fricative. The first experiment illustrates the near-necessity of incorporating aerodynamic data into any study of the dynamic velopharynx. The second experiment bears on the issue of whether or not aerodynamic characteristics may be phonologized and interpreted as features (cf. Clements & Osu 2002). The third experiment addresses the challenges in understanding the not-so-straightforward relationship between aerodynamic events and acoustic output.