A 3D dynamical biomechanical tongue model to study speech motor control

Abstract

A 3D biomechanical dynamical model of human tongue is presented, that is elaborated in the aim to test hypotheses about speech motor control. Tissue elastic properties are accounted for in Finite Element Modeling (FEM). The FEM mesh was designed in order to facilitate the implementation of muscle arrangement within the tongue. Therefore, its structure was determined on the basis of accurate anatomical data about the tongue. Mechanically, the hypothesis of hyperelasticity was adopted with the Mooney-Rivlin formulation of the strain energy function. Muscles are modeled as general force generators that act on anatomically specified sets of nodes of the FEM structure. The 8 muscles that are known to be largely involved in the production of basic speech movements are modeled. The model and the solving of the Lagrangian equations of movement are implemented using the ANSYSTM software. Simulations of the influence of muscle activations onto the tongue shape are presented and analyzed.