Is nonmodal phonation at the end of utterances a cue for speaker recognition by humans?

Abstract

Many studies of nonmodal phonation report a high rate of interspeaker variation. These experiments also showed that the rate and type of glottalization are characteristic to the speaker. Still, it remains an open question whether human listeners use this information as a cue for recognizing familiar voices. A listening experiment was conducted to investigate this issue, concentrating on utterance-final irregularities. Short utterances produced by four speakers were copy synthesized with the Klatt synthesizer in two conditions: with modal and with nonmodal voice quality in their final regions. Because two of the speakers were reliable ‘‘glottalizers’’ and two seldom ‘‘glottalized,’’ one of the two synthesis conditions reflected the speaker’s usual utterance-final voice quality and the other did not. These pairs of stimuli were used to test the effect of the presence or absence of utterance-final nonmodal phonation on the identification of voices familiar to the subjects. When asked to choose which one of the two variants is the speaker’s voice, listeners preferred the stimuli with the speaker’s typical voice quality at the end. Results will be discussed in comparison with a well-known perceptual cue on speaker identity, the F0 contour. [Work supported by a Fulbright Fellowship.]