Vowel change across three age groups of speakers in three regional varieties of American English

Abstract

This acoustic study examines sound (vowel) change in apparent time across three successive generations of 123 adult female speakers ranging in age from 20 to 65 years old, representing three regional varieties of American English, typical of western North Carolina, central Ohio and southeastern Wisconsin. A set of acoustic measures characterized the dynamic nature of formant trajectories, the amount of spectral change over the course of vowel duration and the position of the spectral centroid. The study found a set of systematic changes to /I, ε, æ/ including positional changes in the acoustic space (mostly lowering of the vowels) and significant variation in formant dynamics (increased monophthongization). This common sound change is evident in both emphatic (articulated clearly) and nonemphatic (casual) productions and occurs regardless of dialect-specific vowel dispersions in the vowel space. The cross-generational and cross-dialectal patterns of variation found here support an earlier report by Jacewicz, Fox, and Salmons (2011) which found this recent development in these three dialect regions in isolated citation-form words. While confirming the new North American Shift in different styles of production, the study underscores the importance of addressing the stress-related variation in vowel production in a careful and valid assessment of sound change.

Foreign Language Learners Acquire L2 Phonetic Detail: Goose and Foot Fronting in Non-Native English

“…Koops 2010). Newer formant measurements reported for NAE (Clopper, Pisoni & De Jong 2005;Jacewicz, Fox & Salmons 2011) compared to older acoustic data (Peterson & Barney 1952;Hillenbrand, Getty, Clark & Wheeler 1995) 1 also seem to suggest fronting of the FOOT vowel. In addition, fronted high back vowels are described for English spoken natively in places other than the south of England or the US.…”

“…Hillenbrand et al (1995) report data for northern Midwest. Closest to that are the speakers from southeastern Wisconsin in Jacewicz et al (2011). 2 Cruttenden includes also fronting of /ʊə /.…”

Effects of deafness on acoustic characteristics of American English tense/lax vowels in maternal speech to infants

“…Calculation of vowel space area. Vowel spaces which consist of four vowels have typically been calculated by summing the vowel spaces for two composite three-vowel triangles (Neel, 2008;Fox et al, 2007;Jacewicz et al, 2011). The average F1 and F2 values (Hz) of the four vowels (/i/, /I/, /u/, and /U/) of each speaker were therefore used to calculate the vowel space areas of the /i-u-I/ and /I-u-U/ composite triangles using Heron's method (Kuhl et al, 1997;Liu et al, 2003).…”

The effects of cross-generational and cross-dialectal variation on vowel identification and classification

“…The role of such external factors has been increasingly recognized in the experimental approach to study the acoustics of spoken language, as evident in the rapid growth of the emerging field of sociophonetics (e.g., Foulkes and Docherty, 2006;Labov, 2010;Thomas, 2011). The present study addresses the question of how sociophonetic variation affects the recognition of vowel identity, given the fact that vowels of North American English are split into regional subsystems (e.g., Clopper et al, 2005;Labov et al, 2006) which also undergo dialectspecific internal sound changes (e.g., Labov, 1994;Labov et al, 2006;Jacewicz et al, 2011a;2011c). The emphasis of the study is on dynamic rather than static vowel characteristics.…”

“…This feature may be especially important in maintaining the vowel contrast when both vowels overlap acoustically in the process of generational sound change while reversing the relative positions in the acoustic space. Further discussion and extensive evidence for the cross-dialectal and cross-generational variation in the amount of VISC can be found in Jacewicz et al (2011a;2011c).…”