The role of the pharynx and tongue in enhancement of vowel nasalization : a real-time MRI investigation of French nasal vowels

Complexity in the acoustics of nasal vowels has long been acknowledged but complexity in their articulation has received less attention. A growing body of research suggests that velopharyngeal (VP) opening is complemented by other articulatory gestures which may enhance or counteract the acoustic outcomes of VP opening. In this paper we consider the role of pharyngeal aperture and lingual position in producing the phonemic distinction between oral and nasal vowels in Northern Metropolitan French. The results of a real-time MRI study of one female speaker confirm earlier findings related to tongue height and retraction. The results also suggest a role for the lower pharynx in centralizing the F1 of nasal vowels. Consideration is also given to the effect of the lowered velum on the acoustic transfer function of the oral tract of nasal vowels. We conclude that these articulations enhance some of the wellknown acoustic consequences of VP coupling associated with the production of nasal vowels. This supports and extends the hypothesis that the acoustic characteristics of nasalization can be attained by a family of speech gestures that include, but are not limited to, the opening of the VP port.