D J Zajac
Affiliation: University of North Carolina
- Nasal coarticulation in normal speakers: a re-examination of the effects of genderD J Zajac
University of North Carolina, Chapel Hill 27599, USA
J Speech Lang Hear Res 41:503-10. 1998..Implications relative to aspects of speech production and clinical practice are discussed...
- Nasalance scores of children with repaired cleft palate who exhibit normal velopharyngeal closure during aerodynamic testingDavid J Zajac
University of North Carolina at Chapel Hill, NC, USA
Am J Speech Lang Pathol 22:572-6. 2013..To determine if children with repaired cleft palate and normal velopharyngeal (VP) closure as determined by aerodynamic testing exhibit greater acoustic nasalance than control children without cleft palate...
- Maxillary arch dimensions and spectral characteristics of children with cleft lip and palate who produce middorsum palatal stopsDavid J Zajac
Craniofacial Center, University of North Carolina at Chapel Hill, NC, USA
J Speech Lang Hear Res 55:1876-86. 2012....
- Air pressure responses to sudden vocal tract pressure bleeds during production of stop consonants: new evidence of aeromechanical regulationDavid J Zajac
Craniofacial Center, University of North Carolina, Chapel Hill, NC 27599, USA
J Speech Lang Hear Res 47:784-801. 2004..Implications for understanding speech production and the characteristics of individuals with velopharyngeal dysfunction are discussed...
- Articulation rate and vowel space characteristics of young males with fragile X syndrome: preliminary acoustic findingsDavid J Zajac
University of North Carolina Craniofacial Center, CB 7450, Chapel Hill, NC 27599, USA
J Speech Lang Hear Res 49:1147-55. 2006..The objective of this preliminary study was to determine articulation rate-one component of perceived speaking rate-and vowel space characteristics of young males with FXS...
- Direct magnitude estimation of articulation rate in boys with fragile X syndromeDavid J Zajac
University of North Carolina Craniofacial Center, Chapel Hill, NC, USA
J Speech Lang Hear Res 52:1370-9. 2009..To compare the perceived articulation rate of boys with fragile X syndrome (FXS) with that of chronologically age-matched (CA) boys and to determine segmental and/or prosodic factors that account for perceived rate...
- Pressure-flow characteristics of /m/ and /p/ production in speakers without cleft palate: developmental findingsD J Zajac
University of North Carolina at Chapel Hill, USA
Cleft Palate Craniofac J 37:468-77. 2000..The purpose of this study was to describe the pressure-flow characteristics of a large sample of speakers without cleft palate ranging in age from early childhood to young adulthood...
- Aerodynamic characteristics of tracheostomy speaking valves: an updated reportD J Zajac
University of North Carolina at Chapel Hill, 27599, USA
J Speech Lang Hear Res 42:92-100. 1999..The results of these analyses suggest that although the inspiratory resistance to airflow was similar among various one-way speaking valves, some valves exhibit air loss during speech production...
- Temporal characteristics of aerodynamic segments in the speech of children and adultsDavid J Zajac
UNC Craniofacial Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
Cleft Palate Craniofac J 39:432-8. 2002..A secondary objective was to determine the within-speaker variability of the segments...
- Intraoral pressure and velopharyngeal functionR Mayo
Division of Speech and Hearing Sciences, School of Medicine, UNC Craniofacial Center, Chapel Hill, North Carolina 27599 7450, USA
Cleft Palate Craniofac J 35:299-303. 1998..The objective of this study was to determine the influence of velopharyngeal (VP) inadequacy on respiratory speech compensations...
- The relationship between spectral characteristics and perceived hypernasality in childrenR Kataoka
UNC Craniofacial Center, University of North Carolina at Chapel Hill, 27599 7450, USA
J Acoust Soc Am 109:2181-9. 2001..5 kHz) was associated with an increasing perceived hypernasality. These results suggest that the amplitudes of the three 1/3-octave bands are appropriate acoustic parameters to quantify hypernasality in the isolated vowel [i]...
- Effects of vowel height and vocal intensity on anticipatory nasal airflow in individuals with normal speechL H Young
University of North Carolina at Chapel Hill, USA
J Speech Lang Hear Res 44:52-60. 2001..The results further suggest that anticipatory nasal airflow may be determined by the configuration of the oral cavity to a greater extent in women than in men. Theoretical and clinical implications are discussed...
- Estimation of transpalatal nasalance during production of voiced stop consonants by noncleft speakers using an oral-nasal maskEmily L Bundy
UNC Craniofacial Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
Cleft Palate Craniofac J 43:691-701. 2006..We also determined the relationship between the transpalatal nasalance and fundamental frequency (F0) of the speakers...
- Effects of a pressure target on laryngeal airway resistance in childrenD J Zajac
Craniofacial Center, Department of Dental Ecology, University of North Carolina at Chapel Hill, 27599, USA
J Commun Disord 31:201-12; quiz 212-3. 1998..It is suggested that use of a pressure target during estimation of LAR in children may provide additional data that more accurately reflect the aerodynamic integrity of the larynx. Implications for clinical assessment are discussed...
- The influence of acoustic and perceptual factors on perceived hypernasality in the vowelR Kataoka
UNC Craniofacial Center, University of North Carolina at Chapel Hill, NC, 27599-7450 USA
Folia Phoniatr Logop 53:198-212. 2001..Voice quality deviation and a particular type of spectral change that related to the severity of hypernasality could be factors that influence perceived hypernasality...
- Velopharyngeal function in young and older adult speakers: evidence from aerodynamic studiesD J Zajac
Department of Dental Ecology, University of North Carolina at Chapel Hill 27599, USA
J Acoust Soc Am 102:1846-52. 1997..The nasal air volume results suggest a gender specific velopharyngeal declination effect. Implications for velar motor control strategies are discussed...
- Effects of altered fundamental frequency on nasalance during vowel production by adult speakers at targeted sound pressure levelsKerry C Mandulak
Division of Speech and Hearing Sciences, Department of Allied Health Sciences, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599 7190, USA
Cleft Palate Craniofac J 46:39-46. 2009..This study investigated the effects of altered fundamental frequency (F0) on nasalance levels of the vowels /i/ and /a/ produced by adults without cleft palate within a controlled sound pressure level (SPL) range...
- Assessment of aspiration risk in stroke patients with quantification of voluntary coughC A Smith Hammond
Duke University and Durham Veterans Affairs Medical, Durham, NC, USA
Neurology 56:502-6. 2001..It was hypothesized that aspirating stroke patients would have impaired objective measures of voluntary cough as compared with both nonstroke control subjects and nonaspirating stroke patients...
- Direct measurement of subglottic air pressure while swallowingRoxann Diez Gross
Department of Otolaryngology, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, USA
Laryngoscope 116:753-61. 2006..The primary purpose of this study was to determine if subglottic air pressure is generated during swallowing in a healthy, nontracheostomized person...
- SPEECH AND RESPIRATORY AERODYNAMICS IN CLEFT PALATEDavid Zajac; Fiscal Year: 2003..It is possible, for example, that therapeutic techniques may be developed that incorporate specific respiratory strategies employed by speakers with cleft palate who exhibit acceptable speech characteristics. ..
- Speech Intelligibility Testing in Children with Repaired Cleft PalateDavid Zajac; Fiscal Year: 2007..abstract_text> ..
- Early Assessment of Infants with Cleft Palate Following Surgical RepairDavid Zajac; Fiscal Year: 2008..unreadable] [unreadable] [unreadable]..