Acoustic and ultrasound investigation of English vowel-to-vowel coarticulation.

Abstract

This study examined the hypothesis of whether vowel‐to‐vowel coarticulation effects are stronger when a particular vowel segment is under focus in clarified speech than when it is not under a condition of focus. In one condition, native speakers of American English produced disyllabic word pairs that varied in the quality of their first vowel (stressed V1), while in the second condition, the same group of speakers produced the word pairs that varied in the quality of their second vowel (V2). The degree of coarticulation was determined by the amount of spectral and/or articulatory displacement that occurred during the production of V2‐position [schwa] due to the influence of V1. Due to the need to increase the likelihood of coarticulatory effects during speakers’ productions, recording trials were sped up to a conversational speaking rate. Spectral measurements (first and second formants) of ə in both conditions were taken, as well as tongue‐surface position measurements pertaining to the position of tongue body during the production of ə under the two conditions. Preliminary acoustic analysis indicates that speakers produced V2‐position ə with greater coarticulatory effects in the V1‐clarifying condition than in the V2‐clarifying condition.