title: Velopharyngeal function during vocalization in infants.
abstract: OBJECTIVE
  To determine the age at which infants achieve velopharyngeal closure during vocalization.
  
  
  METHODS
  Longitudinal with repeated measures.
  
  
  METHODS
  Laboratory.
  
  
  METHODS
  Six healthy infants were studied monthly from ages 2 to 6 months while they interacted with a parent and an investigator.
  
  
  METHODS
  The presence or absence of velopharyngeal closure, as determined by sensing ram pressure at the anterior nares.
  
  
  RESULTS
  The velopharynx was open for windups, whimpers, and laughs, and it was closed for cries, screams, and raspberries, regardless of age. The frequency with which the velopharynx closed during syllable utterances increased significantly with age.
  
  
  CONCLUSIONS
  Velopharyngeal closure for speech-like utterance increases with age, but is not complete and is still undergoing development at 6 months of age. Velopharyngeal closure during infancy may be influenced by pressure demands of the utterance; however, support for this speculation is stronger for other types of utterances than it is for speech-like utterances. The method used in this study holds promise for evaluating infants with suspected velopharyngeal impairment.
authors.affiliation: Department of Speech, Language, and Hearing Sciences, University of Arizona, Tucson, Arizona 85721, USA.
authors.forename: Stacey A
authors.initials: SA
authors.lastname: Thom
authors.forename: Jeannette D
authors.initials: JD
authors.lastname: Hoit
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Hixon
authors.forename: Alice E
authors.initials: AE
authors.lastname: Smith
mesh_terms: D000367:Age Factors; D002663:Child Language; D002675:Child, Preschool; D003448:Crying / Q000502:physiology; D005260:Female; D006801:Humans; D007223:Infant; D008137:Longitudinal Studies; D008297:Male; D010160:Palate, Soft / Q000502:physiology*; D010609:Pharyngeal Muscles / Q000502:physiology; D010614:Pharynx / Q000502:physiology*; D011312:Pressure