Predicting the effect of talker differences on perceived vowel category.

Abstract

It has been clear for more than 50 years that listeners sometimes shift their categorization of target vowels as a function of the information in preceding carrier phrases. These results have been interpreted as evidence for a talker normalization process that allows listeners to tune their speech perception to the peculiarities of individual talkers. However, it is still not clear what information is being extracted about the talker from the context phrases. In the current set of studies, carrier phrases (“He had a rabbit and a”) spoken by different “talkers” were produced by manipulating the length and oral/pharyngeal cavity ratios of an articulatory synthesizer. [Story, J. Acoust. Soc. Am. 117, 3231–3254 (2005).] These phrases preceded a series of target stimuli varying from “bit” to “bet” produced by the standard vocal tract for the synthesizer. Shifts in the perceived target vowel were obtained for some of these vocal tract manipulations but not others. The presence/absence of effects was most readily predictable from the long‐term spectral average of the carrier phrase. These results support the idea that listeners are extracting general acoustic information from the context and not specific information about the talker’s vocal tract. [Work supported by NIH‐NIDCD.]