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The purpose of this study was to investigate the effect of production time on the perception of disordered nasalization in children with cleft palate. The subjects with cleft palate included 5 who produced acceptable speech consistently, 5 who produced disordered nasalization consistently, and 10 who were inconsistent in the production of disordered nasalization. We examined a range of production times similar to those for the production of single-word and connected speech tasks. Ten judges used direct magnitude estimation to rate severity of disordered nasalization. An accelerometric ratio technique was used to estimate the extent and timing of nasal acoustic activity. The results showed that reducing the production time did not change perceptible nasalization.

This study determined whether children could learn to replicate four positions of lingual-palatal contact with and without topical anesthesia that eliminated touch-pressure sensations. First-grade boys, nine with good articulation skills and nine with poor articulation skills, were used as subjects. Results suggest that individuals are able to learn nonspeech tasks of tongue positioning by relying on muscle spindles or deep receptors within the tongue, or both, or by relying on lingual touch-pressure or other surface receptors within the tongue, or, by a combination of deep and surface receptors of the tongue. Further, tongue positioning need not be dependent on touch-pressure or superficial tactile mechanisms. Children with relatively severe articulation problems performed more poorly on the tasks of precise tongue placement than children with good articulation skills. And finally, children with relatively severe articulation problems may be able to improve their initially poor performance on tongue placement tasks with specific training on those tasks, implying that this group did receive the intraoral sensory feedback necessary to learn the task, but that more experience was needed for the learning to occur.

Velar and pharyngeal wall displacements were studied simultaneously by using conventional lateral-view radiography and frontal-view tomography. Twenty-five normal adult male and female subjects were utilized. Major results pertaining to lateral pharyngeal wall displacements during speech include the following. 1) At more superior levels of the pharynx, greater mesial displacements occurred for nonnasal compared to nasal speech sounds and no significant differences were noted among the nonnasal speech sounds studied. 2) At an inferior level of the pharynx, mesial displacements were greater for low vowels compared to the other speech sounds studied but some lateral (outward) movements were observed during high vowel production for some subjects. 3) Greatest mesial displacements for all subjects ad speech sounds studied occurred at the level of and just below the plane of the hard palate. Low correlations between velar and lateral pharyngeal wall displacements were obtained for most subjects. The results do not support the hypothesis that the levator veli palatini muscle is solely involved in both velar and lateral pharyngeal wall movements.

The purpose of this study was to examine the relationships between several temporal measures of speech movements and perceived nasalization in speakers with cleft palate. Four adult subjects with repaired cleft palate were filmed using high-speed (100 frames/s) cinefluorography as they produced target syllables embedded in a carrier phrase. Perceived nasalization of each extracted acoustic target syllable was rated by 18 trained judges. Movements of the tongue tip, tongue dorsum, jaw, velar knee, velar tip, and posterior pharyngeal wall were plotted over time. Time of movement onsets and movement offsets was identified from the plots. Voice onset and offset times were identified from the synchronized acoustic recordings. The findings indicate that normally expected velopharyngeal movements occurred near the time of jaw-lowering onset during nasalized CVC and CVN productions in two subjects who were judged to exhibit high levels of nasalization. The other two subjects showed no velopharyngeal movements during the CVC production. It is speculated that velopharyngeal movements normally expected in CVC utterances may be avoided by some speakers with cleft palate in order to minimize perceptible nasalization.