title: The effect of age of cochlear implantation on vocal characteristics in children.
abstract: BACKGROUND
  Early cochlear implantation aids auditory feedback and supports better communication and self-monitoring of the voice. The objective of this study was to determine whether the age of cochlear implantation has an impact on vocal development in children implanted before age 4.
  
  
  METHODS
  The study consisted of 19 participants in total. All implant recipients (experimental group) were 3-5 years post-implantation, including four prelingual (0-2 years) and five perilingual (2-4 years) implant recipients. The control group consisted of 10 children whose hearing was within normal limits between the ages 3-6 years and 10 months, which was compared to the experimental group. Established paediatric norms were used for additional comparison. A questionnaire was used to gather information from each of the participant's caregivers to determine whether other personal and contextual factors had an impact on voice production. An acoustic analysis was conducted for each participant using the Multi-Dimensional Voice Program of the Computerized Speech Lab.
  
  
  RESULTS
  When the experimental group and the control group were compared, similar results were yielded for fundamental frequency and short-term perturbation (jitter and shimmer). More variability was noted in long-term frequency and amplitude measures, with significantly higher differences, and therefore further outside the norms, in the prelingual group when compared to the perilingual and control groups.
  
  
  CONCLUSIONS
  In this study, age of implantation did not impact vocal characteristics. Further research should include larger sample sizes, with participants that are age and gender matched.
authors.forename: Kerry
authors.initials: K
authors.lastname: Knight
authors.forename: Simone
authors.initials: S
authors.lastname: Ducasse
authors.forename: Ashley
authors.initials: A
authors.lastname: Coetzee
authors.affiliation: Department of Speech-Language Pathology and Audiology, University of Pretoria. jeannie.vanderlinde@up.ac.za.
authors.forename: Jeannie
authors.initials: J
authors.lastname: van der Linde
authors.forename: Anel
authors.initials: A
authors.lastname: Louw
mesh_terms: D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D019929:Cochlear Implantation; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007223:Infant; D007805:Language Development Disorders / Q000175:diagnosis / Q000517:prevention & control / Q000628:therapy*; D008297:Male; D012016:Reference Values; D013018:Sound Spectrography; D013061:Speech Acoustics; D013068:Speech Production Measurement; D014833:Voice Quality
keywords: cochlear implant; vocal development; age of implantation; prelingual; lingual.