ASA 129th Meeting - Washington, DC - 1995 May 30 .. Jun 06

5aSC11. A computational model using formant space planning of articulator movements for vowel production.

Frank H. Guenther

Dept. of Cognitive and Neural Systems, Boston Univ., 111 Cummington St., Rm. 244, Boston, MA 02215

Dave Johnson

Boston Univ., Boston, MA

It is often hypothesized that articulator movements are planned within a coordinate frame whose variables correspond to key vocal tract constrictions [e.g., E. Saltzman and K. G. Munhall, Ecol. Psych. 1, 333--382 (1989)]. However, recent evidence suggests that speakers may utilize a more acoustic-like space for planning vowel movements [J. Perkell et al., 2948--2961 (1993)]. Previous work has verified the capacity of a computational speech production model called DIVA to explain a wide range of experimental data using a constriction planning space. The current work extends the model to allow formant space planning of vowel movements. The model learns target regions for F1 and F2 for each vowel during a babbling cycle. A mapping between desired formant changes and articulator movements that achieve these changes is also learned. After babbling, the model successfully reaches all vowel targets from any initial vocal tract configuration, even in the presence of constraints such as a blocked jaw, and the resulting synthesized vowels are easily recognizable. Although vowel targets specify only formant ranges with no articulatory information, articulator configurations used by the model to produce vowels are similar to human configurations. [Work supported by AFOSR F49620-92-J-0499.]