Jerald B. Moon

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This study examined temporal parameters of speech in subjects with apraxia of speech, conduction aphasia, and normal speech. They were asked to repeat target words in a carrier phrase 10 times. Acoustic analyses involved measurement of stop gap duration, voice onset time, vowel nucleus duration, and consonant-vowel (CV) duration. Speakers with apraxia of(More)
The purpose of this study was to measure velopharyngeal closure force in varying phonetic contexts for normal men and women subjects. Levator veli palatini muscle activity was measured as well. Place and manner of articulation, voicing, and the effects of consonant sequencing were studied in different vowel contexts. When the data were grouped by sex of(More)
OBJECTIVE As a step toward better understanding of normal and abnormal velar control, a finite element model of the soft palate was developed. DESIGN A static two-dimensional midsagittal model of the velum was given physical dimensions to match that of a 10-year-old boy. Biomechanical properties of the tissues were inferred based on previous histologic(More)
Vocal tract pressures during speech tend to be maintained in the face of airway leaks that might be encountered by individuals with repaired palatal clefts. This study tested the hypothesis that such constant pressures can be explained as a consequence of constant pressure source characteristics of the respiratory system during speech production. This(More)
A comparison of the ranges of levator veli palatini EMG activity for speech versus a nonspeech task for subjects with cleft palate was the focus of this study. EMG values are also compared with subjects without cleft palate obtained in a previous study. Hooked-wire electrodes were inserted into the levator muscle of five adult subjects with cleft palate(More)
The purposes of this study were to (a) design and test a new velopharyngeal closure force sensing bulb, and (b) use the closure force bulb to gather additional information on the variations in closure force associated with different vowels. The closure force sensing bulb possessed a flat frequency response to 30 Hz. Its output was highly linear relative to(More)
This study was conducted to (a) study the ability of young adult subjects to track target signals with the lower lip, jaw, or larynx, (b) examine subjects' abilities to track different sinusoidal frequencies and unpredictable target signals, and (c) test notions of response mode and predictive mode tracking reported for nonspeech structures by previous(More)
This investigation was designed to measure the ability of normal adult speakers to exert voluntary control over velopharyngeal positioning. Speakers were asked to phonate the vowels [a] and [i] at 50 percent and 75 percent of complete velopharyngeal closure, using visual feedback of velopharyngeal opening and closing gestures from a phototransducer. The(More)
The relative contributions of the levator veli palatini, palatoglossus, and palatopharyngeus muscles were assessed relative to a range of positions of the velopharynx during production of the vowels [a] and [i] by four normal adult speakers. The results indicate that velopharyngeal positioning is determined by the relative contributions of the levator veli(More)
Innocuous mechanical stimuli were applied to eight sites on the tongue dorsum and palate while subjects used feedback to maintain a constant isometric biting force. Reflex responses of the jaw-closing system were measured as changes in force and in EMGs recorded from right and left masseter muscles. Stimulation at each of the eight sites produced reflex(More)