title: Speech sample effects on pressure and flow measures in children with normal or abnormal velopharyngeal function.
abstract: OBJECTIVE
  This study examined the effect of certain test phoneme contexts on oral pressure and nasal flow values in young children with normal velopharyngeal (VP) function. Comparison was made with responses from children with abnormal function. SPEAKERS: Ten children judged to have normal VP function (mean age = 5.2 years) and five children with VP incompetence (mean age = 7.8 years) were evaluated. Both groups were able to produce the speech sample with standard articulatory postures. Subjects were from the local community and a university cleft palate clinic.
  
  
  METHODS
  Simultaneous oral pressure and nasal flow recordings were obtained from the speakers as they produced /p/ in speech stimuli that varied in terms of test phoneme position in the syllable (releasing and arresting), adjacent vowel height (high, middle, and low), or adjacent consonant characteristics (voicing, placement, and manner). Within-subject differences in pressure and flow were examined to evaluate specific stimulus contrasts in each speaker group.
  
  
  METHODS
  Data were collected in the Speech Physiology Laboratory in the Hearing and Speech Department at the University of Kansas Medical Center.
  
  
  RESULTS
  There were few speech sample effects on oral pressure for children with VP competence. Nasal flow for this group occurred infrequently but was present at least once in 80% of the subjects. The speakers with VP incompetence demonstrated predictable phoneme context effects (higher flow and lower pressure for a nasal context; higher flow for a high vowel context).
  
  
  CONCLUSIONS
  The finding of no significant stimulus effects for the normal speakers suggests the need for little concern when choosing stimuli for normative study of oral pressure. However, certain stimulus contexts should be considered for data collection if results are to be applied to children with abnormal velopharyngeal function.
authors.affiliation: Hearing and Speech Department, University of Kansas Medical Center, Kansas City 66160-7605, USA.
authors.forename: J P
authors.initials: JP
authors.lastname: Searl
authors.forename: M A
authors.initials: MA
authors.lastname: Carpenter
mesh_terms: D000161:Acoustic Stimulation; D000399:Air Pressure; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D008297:Male; D010700:Phonetics; D015203:Reproducibility of Results; D012212:Rheology; D013060:Speech / Q000502:physiology*; D013068:Speech Production Measurement; D014681:Velopharyngeal Insufficiency / Q000503:physiopathology*