Phonetic and phonological patterns of nasality in Lakota vowels

Abstract

Lakota (Siouan) has both contrastive and coarticulatory vowel nasality, and both nasal and oral vowels can occur before or after a nasal consonant. This study examines the timing and degree patterns of acoustic vowel nasality across contrastive and coarticulatory contexts in Lakota, based on data from six Lakota native speakers. There is clear evidence of both anticipatory and carryover nasal coarticulation across oral and nasal vowels, with a greater degree of carryover than anticipatory nasalization. Nasality in carryover contexts is nonetheless restricted: the oral–nasal contrast is neutralized for high back vowels in this context and realized for three of the six speakers in low vowels. In the absence of nasal consonant context, contrastive vowel nasalization is generally greatest late in the vowel. Low nasal vowels in carryover contexts parallel this pattern (despite the location of the nasal consonantbeforethe vowel), and low nasal vowels in anticipatory contexts are most nasal at the start of the vowel. We relate the synchronic patterns of coarticulation in Lakota to both its system of contrast and diachronic processes in the evolution of nasality in Lakota. These data reflect that coarticulatory patterns, as well as contrastive patterns, are grammatical and controlled by speakers.