Listener’s variation in phoneme category boundary as a source of sound change: A case of /u/-fronting.

Abstract

Previous work examined listeners’ recognition of a vowel in a series of [dVt] and [bVp] syllables varying perceptually from /CiC/ to /CuC/ in four different conditions (without precursor phrase, with precursor phrase, and in fast, medium, and slow speech), and found that ambiguous vowel stimuli were more often heard as /u/ in the [dt] context as opposed to the [bp] context (compensation for coarticulation). This paper reports the results of further analysis of the data and shows that although listeners varied in their /i/-/u/ category boundaries, their perceptual responses were systematic so that a group of listeners who had the category boundary closer to the /i/-end than the rest of the listeners in the “no-precursor” condition consistently had it this way in other conditions as well. This study also investigated the listeners’ response in vowel repetition task, where the listeners were asked to listen to the same [CVC] stimuli as used in the vowel recognition task and to repeat only the vowel. Results of this part of the study will be presented and the implications for a listener-based theory of sound change will be discussed.