Glottal waveform characteristics of deaf speakers
James J. Mahshie · The Journal of the Acoustical Society of America · 1991
The distinctive voice quality that characterizes many deaf individuals suggests that they use phonatory adjustments for speech production that differ from normal. Little research, however, has been reported that examines the phonatory attributes of deaf individuals. The purpose of the present work was to examine glottal volume velocity waveform characteristics of deaf speakers, and to compare these characteristics to those of normal-hearing talkers. The oral airflow signals associated with non-nasalized vowels produced by five deaf and five normal-hearing subjects were inverse filtered, and the resultant signals examined. In addition to qualitative waveform descriptions, measures were made characterizing cycle-to-cycle peak volume velocity, duty cycle characteristics, and amount of unmodulated airflow (do offset of the volume velocity signal). Result thus far reveal systematic differences from normal for some of the deaf speakers, while others, particularly those with voice quality perceived as less aberrant, had glottal waveform patterns similar to those observed in the normal-hearing subjects. Procedural issues for obtaining and analyzing the glottal waveforms of deaf individuals, and the implications of the findings of speech intelligibility and naturalness of deaf speakers, will be discussed. [Work supported by the Whitaker Foundation.]