Sixth International Conference on Spoken Language Processing
(ICSLP 2000)

Beijing, China
October 16-20, 2000

Degrees of Freedom of Tongue Movements in Speech may be Constrained by Biomechanics

Pascal Perrier (1), Joseph Perkell (2), Yohan Payan (3), Majid Zandipour (2), Frank Guenther (4), Ali Khalighi (1)

(1) Institut de la Communication Parlée, Université Stendhal - Grenoble, France
(2) Speech Communication Group, MIT, Cambridge, MA, USA
(3) TIMC - Université Joseph Fourier, Grenoble, France
(4) CNS-CAS, Boston University, Boston, MA, USA

A number of studies carried out on different languages have found that tongue movements in speech are made along two primary degrees of freedom (d.f.s): the high-front to low-back axis and the high-back to low-front axis. We explore the hypothesis that these two main d.f.s could find their origins in the physical properties of the vocal tract. A large set of tongue shapes was generated with a biomechanical tongue model using a Monte-Carlo method to thoroughly sample the muscle control space. The resulting shapes were analyzed with PCA. The first two factors explain 84% of the variance, and they are similar to the two experimentally observed d.f.s. This finding suggests that the d.f.s. are not speech-specific, and that speech takes advantage of biomechanically based tongue properties to form different sounds.

Full Paper

Bibliographic reference.  Perrier, Pascal / Perkell, Joseph / Payan, Yohan / Zandipour, Majid / Guenther, Frank / Khalighi, Ali (2000): "Degrees of freedom of tongue movements in speech may be constrained by biomechanics", In ICSLP-2000, vol.2, 162-165.