Stress and Boundary Effects on Anticipatory and Preservatory Nasal Airflow

The present study examined the effects of boundary strength and stress on nasal coarticulation with neighboring segments. Acoustic and nasal airflow data were recorded from four speakers as they produced intervocalic fricative-nasal and nasalfricative sequences that spanned a word-internal boundary or a word boundary under two different stress conditions. Although neither stress nor boundary affected preservatory nasal airflow, tautosyllabic stress was associated with increased anticipatory nasal airflow within a word, but not at the a word boundary where coarticulation decreased or stayed the same. The interaction between boundary strength and stress was attributed to condition-dependent differences in the relative durations of individual segments. Overall, the study suggests that stress-induced lengthening of a velar gesture results in the leftward spread of nasality if adjacent segments are not also substantially lengthened by prosodic factors.