Voicing Distinction in Esophageal Speech

Abstract

In order to analyze the articulatory ability of skilled esophageal speakers in terms of the voicing distinction in consonants, perceptual, acoustical and physiological studies were conducted. It was found that voiced-voiceless confusion was only 10.5% on average in the present subjects. Acoustical analysis indicated that voice onset time (VOT) values in word-initial position and the presence or absence of voicing in word-medial position were most important cues for the voicing distinction of consonants in esophageal speech. Fiber-optic and photoglottographic examinations revealed that there was a transient opening of the neoglottis for the production of voiceless sounds, while it stayed closed for voiced sounds. Immediately before the period of voicelessness, surface EMG obtained from the anterior neck appeared to show transient activation. There was a tendency that peak intraoral pressure values for the voiceless stops were significantly higher in the esophageal speakers than in the normal subject, whereas the values for voiced cognates were rather close to those of the normal.