Variation in back vowel fronting and diphthongization in Louisiana English

Abstract

Fronting of /u o ʊ/ vowel classes is prominent in Southern American English (SAE). This study was focused on Louisiana, a southern state where not all SAE features have had a strong hold. Dynamic formant trajectories of the target vowels were analyzed because different vowel fronting mechanisms were proposed for SAE and mainstream American English (Koops, 2010), and because formant trajectories of back vowels are rarely examined (Stanley and Renwick, 2020). Thirteen White and five Black college-aged females produced 24 monosyllabic words with vowels of each class as a part of a larger study. In White speakers, mean normalized F2 values at midpoints of /u o ʊ/ were not different from each other or from the central vowel /ʌ/, used as a reference. In Black speakers, /ʊ/'s F2 was similar to /ʌ/, but /u o/'s F2 was lower than in /ʌ/. In all speakers, formant trajectories of /u o/ were back-gliding, while /ʊ/ was center-gliding. Trajectory lengths of /u o/ were longer in White than in Black speakers. These results suggest that /u/ fronting was mainstream-like (nucleus fronting and a backglide) and that /u o/ fronting was more advanced in White than in Black female speakers.