An articulatory and acoustic study of fricative consonants /s/ and /sh/ in normal and post-glossectomy speakers

Abstract

Glossectomy is a surgical procedure to remove the cancerous tumor of the tongue. After the glossectomy, the tongue is sutured closed or a flap is inserted to reconstruct the tongue volume. As a result, the properties of the tongue are more or less affected by the surgery. The changes in the tongue properties may also affect the speech production abilities of the post-glossectomy speaker. This study examined the production of the fricative consonants /s/ and /sh/ in normal and post-glossectomy speakers. The data analyzed consisted of audio and magnetic resonance images from dozens of normal and glossectomy speakers. An acoustic analysis showed that the average centers of gravity of /s/ and /sh/ in glossectomy speakers are significantly lower than in normals. This difference may be explained by a more posterior constriction in glossectomees due to the surgery. Examination of the tongue shapes in midsagittal MR images showed that they tend to have more laminal /s/ than apical /s/. 3-D vocal tracts of /s/ and /sh/ were reconstructed for three glossectomy speakers whose /s/ and /sh/ cannot easily be discriminated in listening tests. Details of the 3-D vocal tract shapes, along with their acoustic implications, will be discussed for the glossectomy and normal speakers. [This research was supported by NIH R01 CA133015.]