Special issue on Motor Control

Learning to speak. Sensori-motor control of speech movements
by Gérard Bailly
Institut de la Communication Parlée, Grenoble, France
Speech Communication Vol. 22 (2/3)

N.B. : All the digital files associated with this article are in a QuickTime movie (.mov) format;

Description of movies

• All simulations start from a neutral posture except when explicitly noted;
• The attractors are represented by ellipsis. The colour of each ellipsis is correlated with activation: no activation is white, maximum activation is dark blue;
• Top panels show how the movement is planned and controlled in acoustic and/or proprioceptive maps. Left: "acoustic" attractors in superimposed F2/F1 and F3/F1 planes. Right: "proprioceptive" attractors (when activated). Crosses show the position of the actual frame in both representation planes;
• Bottom panels show the acoustic and gestural characteristics of the movement. Left: formant tracks in a Bark scale. Right: the mid-sagittal movement with a front view of the lips.

Simple vocalic gestures - The articulators are attracted by a force field induced by an "acoustic" force field. This "acoustic" force field is generated by progressively activating the Gaussian attractor of a given vowel.

Movie 1 [114 kB]
[a] attractor

Movie 2 [121 kB]
[i] attractor

Movie 3 [111 kB]
[u] attractor

Movie 4 [119 kB]
[u] attractor with a lip-tube

Chaining gestures - Force fields are generated, back-projected and overlapped: "acoustic" for vowels and "geometric" for plosives. The resulting "articulatory" force field drives the articulators.

Movie 5 [276 kB]
sequence [aiu] obtained by chaining [a] [i] and [u] attractors

Movie 6 [218 kB]
same for the sequence [abi]