Spectral change in the front vowels of North American English.

Abstract

Assmann and Nearey [J. Acoust. Soc. Am. 80, 1297–1308 (1986)] coined the term “vowel‐inherent spectral change” (VISC) to refer to change in spectral properties inherent to the phonetic specification of vowels. Although VISC includes the relatively large formant movements associated with acknowledged diphthongs, it was explicitly extended to include reliable (but possibly more subtle) spectral change associated with vowel categories of North American English typically designated as monphthongs. This paper reviews statistical evidence of VISC in the formant patterns in front vowels of /hVd/ syllables in three regional dialects of English: Dallas, TX [Assmann and Katz, J. Acoust. Soc. Am. 108, 1856–1866 (2000)], Western, MI [Hillenbrand et al., J. Acoust. Soc. Am. 97, 3099–3111 (1995)] and Northern, AB (new data). Results suggest that VISC patterns may be useful characteristics for assessing dialect differences. Evidence is presented for the importance of VISC in vowel perception, including recent evidence from our laboratories regarding perception by second language learners. A progress report is provided on research into how VISC is best characterized parametrically and which temporal regions of a vocoid may be most effective in summarizing VISC patterns in varying consonantal contexts.