Abstract
This paper presents the measurement of three-dimensional shapes of vocal tract and dental crown using magnetic resonance imaging (MRI). 3D MR images of the vocal tract of 3 adult males were obtained in the steady state productions of Japanese fricatives /s/, /sh/ and /shu/ using a dental crown plate contain a contrast medium for MR imaging. MR images and the voice output uttered by a supine subject in the MR system were obtained simultaneously. The measurement time was 186 second for 41 axial sections from the larynx to the nasal cavity at a 4mm interval, and was 186 second for 32 coronal sections from the tip of the nose to the atlas at a 4mm interval. Frequency characteristics of the voice output /shu/ showed results specificity in each subjects. 3D shapes and area function of vocal tract during the productions of Japanese fricatives /s/, /sh/, and /shu/ were obtained from arbitrary sections computed by gray level interpolation. Several narrow points that were considered articuration points were detected in vocal tract from these results of measurements.
