Towards the automatic study of the vocal tract from magnetic resonance images

• Author(s): Maria João M. Vasconcelos ; Sandra M. Rua Ventura ; Diamantino Rui S. Freitas ; João Manuel R. S.Tavares
• Date: 2011
• Persistent ID: http://hdl.handle.net/10216/56925
• Origin: Repositório Aberto da Universidade do Porto
• Subject(s): Ciências tecnológicas; Tecnologia; Tecnologia de computadores; Processamento de imagem
• Document Type: Article
• Language: English

Description

Over the last few decades, researchers have been investigating the mechanisms involved in speech production. Image analysis can be a valuable aid in the understanding of the morphology of the vocal tract. The application of magnetic resonance imaging to study these mechanisms has been proven to be reliable and safe. We have applied deformable models in magnetic resonance images in order to conduct an automatic study of the vocal tract; mainly, to evaluate the shape of the vocal tract in the articulation of some European Portuguese sounds, and then to successfully automatically segment the vocal tract’s shape in new images. Thus, a Point Distribution Model has been built from a set of magnetic resonance images acquired during artificially sustained articulations of twenty one sounds, which successfully extracts the main characteristics of the movements of the vocal tract. The combination of that statistical shape model with the grey levels of its points are subsequently used to build Active Shape Models and Active Appearance Models. Those models have then been used to segment the modelled vocal tract into new images in a successful and automatic manner. The computational models have thus been revealed to be useful for the specific area of speech simulation and rehabilitation, namely to simulate and recognize the compensatory movements of the articulators during speech production.