Vowel acoustic characteristics of Southern American English variation in Louisiana.

This study examined acoustic characteristics of vowels produced by speakers from Louisiana, one of the states in the Southern English dialect region. First, how Louisiana vowels differ from or are similar to the reported patterns of Southern dialect were examined. Then, within-dialect differences across regions in Louisiana were examined. Thirty-four female adult monolingual speakers of American English from Louisiana, ranging in age from 18 to 23, produced English monosyllabic words containing 11 vowels /i, ɪ, e, ɛ, æ, ʌ, u, ʊ, o, ɔ, ɑ/. The first two formant frequencies at the midpoint of the vowel nucleus, direction, and amount of formant changes across three different time points (20, 50, and 80%), and vowel duration were compared to previously reported data on Southern vowels. Overall, Louisiana vowels showed patterns consistent with previously reported characteristics of Southern vowels that reflect ongoing changes in the Southern dialect (no evidence of acoustic reversal of tense-lax pairs, more specifically no peripheralization of front vowels). Some dialect-specific patterns were also observed (a relatively lesser degree of formant changes and slightly shorter vowel duration). These patterns were consistent across different regions within Louisiana.