Velopharyngeal Gap Size During Sustained Vowel Production Correlates With Perceptual Ratings of Hypernasality in Connected Speech.

Purpose: The purpose of this study was to investigate the relationship between perceptual ratings of hypernasality made during connected speech and velopharyngeal (VP) gap size measured in millimeters in the sagittal plane during sustained vowel production using magnetic resonance imaging (MRI).

Method: A retrospective cross-sectional analysis was completed. A subgroup of 110 participants from another study with an of 10.

The relation of velopharyngeal coupling area and vocal tract scaling to identification of stop-nasal cognates.

The purpose of this study was to determine whether the threshold of velopharyngeal (VP) coupling area at which listeners switch from identifying a consonant as a stop to a nasal in North American English was different for speech produced by a model based on an adult male, an adult female, and a 4-year-old child. V1CV2 stimuli were generated with a speech production model that encodes phonetic segments as relative acoustic targets imposed on an underlying vocal tract and laryngeal structure that can be scaled according to sex and age. Each V1CV2 was synthesized with a set of VP coupling functions whose maximum area ranged from 0 to 0.

Identification of voiced stop consonants produced by acoustically driven vocal tract modulations.

A recently developed speech production model, in which speech segments are specified by relative acoustic events called resonance deflection patterns, was used to generate speech signals that were presented to listeners in a perceptual test. The purpose was to determine the effect of variations of the magnitude and polarity of the third resonance deflection on identification of the consonant in a VCV disyllable while the deflections of the first and second resonances were held constant. Result showed that listeners' identification changed from /d/ to /ɡ/ when the polarity of the third resonance deflection switched from positive to negative.

The relation of velopharyngeal coupling area to the identification of stop versus nasal consonants in North American English based on speech generated by acoustically driven vocal tract modulations.

The purpose of this study was to determine the threshold of velopharyngeal coupling area at which listeners switch from identifying a consonant as a stop to a nasal in North American English, based on VCV stimuli generated with a speech production model that encodes phonetic segments as relative acoustic targets. Each VCV was synthesized with a set of velopharyngeal coupling functions whose area ranged from 0 to 0.1 cm.

A model of speech production based on the acoustic relativity of the vocal tract.

A model is described in which the effects of articulatory movements to produce speech are generated by specifying relative acoustic events along a time axis. These events consist of directional changes of the vocal tract resonance frequencies that, when associated with a temporal event function, are transformed via acoustic sensitivity functions, into time-varying modulations of the vocal tract shape. Because the time course of the events may be considerably overlapped in time, coarticulatory effects are automatically generated.