title: Effects of early auditory experience on word learning and speech perception in deaf children with cochlear implants: implications for sensitive periods of language development.
abstract: OBJECTIVE
  That early word learning and speech perception skills have different sensitive periods and that very early implantation may affect later vocabulary outcomes more than speech perception outcomes.
  
  
  BACKGROUND
  Several studies have found that deaf children who receive cochlear implants before 3 years of age tend to have better speech perception outcomes than children implanted later. Recent studies have not found age-at-implantation effects on speech perception or central auditory processing among children implanted younger than 2 years, suggesting that there may be a sensitive period for speech perception skills that closes by around 3 years of age. There has been very little work investigating possible sensitive periods for other language skills, such as the ability to learn words. Recent work suggests the possibility that the development of word-learning skills may have an earlier sensitive period than the development of speech perception skills.
  
  
  METHODS
  Assess speech perception and vocabulary outcomes in children implanted before 13 months of age and in children implanted between 16 and 23 months of age.
  
  
  RESULTS
  Children implanted during the first year of life had better vocabulary outcomes than children implanted during the second year of life. However, earlier implanted children did not show better speech perception outcomes than later implanted children.
  
  
  CONCLUSIONS
  There may be an earlier sensitive period for developing the ability to associate the sound patterns of words to their referents than for developing speech perception and central auditory processing skills.
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Indiana University School of Medicine, Indianapolis, Indiana 46202, USA. dmhousto@indiana.edu
authors.forename: Derek M
authors.initials: DM
authors.lastname: Houston
authors.forename: Richard T
authors.initials: RT
authors.lastname: Miyamoto
mesh_terms: D000367:Age Factors; D002675:Child, Preschool; D019929:Cochlear Implantation; D003054:Cochlear Implants; D003423:Critical Period, Psychological; D003638:Deafness / Q000503:physiopathology / Q000601:surgery*; D006801:Humans; D007223:Infant; D007804:Language Development; D013067:Speech Perception / Q000502:physiology*; D016896:Treatment Outcome; D014825:Vocabulary
references.citation: Ann Otol Rhinol Laryngol Suppl. 2002 May;189:49-51
references.pmid: 12018348
references.citation: Volta Rev. 1999;101(3):111-164
references.pmid: 21666760
references.citation: Ear Hear. 2002 Dec;23(6):532-9
references.pmid: 12476090
references.citation: Neuroreport. 2002 Jul 19;13(10):1365-8
references.pmid: 12151804
references.citation: Dev Psychobiol. 2005 Apr;46(3):252-61
references.pmid: 15772969
references.citation: J Psycholinguist Res. 2009 Jun;38(3):305-19
references.pmid: 19337839
references.citation: Arch Otolaryngol Head Neck Surg. 2004 May;130(5):570-4
references.pmid: 15148178
references.citation: J Deaf Stud Deaf Educ. 2009 Winter;14(1):44-62
references.pmid: 18495655
references.citation: Int J Pediatr Otorhinolaryngol. 2003 May;67(5):479-95
references.pmid: 12697350
references.citation: J Speech Lang Hear Res. 2005 Aug;48(4):853-67
references.pmid: 16378478
references.citation: J Speech Lang Hear Res. 2004 Jun;47(3):509-26
references.pmid: 15212565
references.citation: Ear Hear. 2007 Apr;28(2 Suppl):11S-18S
references.pmid: 17496638
references.citation: Int J Audiol. 2004 Oct;43(9):506-15
references.pmid: 15726841
references.citation: Audiol Neurootol. 2004 Jul-Aug;9(4):224-33
references.pmid: 15205550
references.citation: J Child Lang. 1987 Feb;14(1):23-45
references.pmid: 3558524
references.citation: J Cogn Neurosci. 2004 Oct;16(8):1412-25
references.pmid: 15509387
references.citation: Int J Audiol. 2007 Sep;46(9):494-9
references.pmid: 17828665
references.citation: Psychol Sci. 2003 Jan;14(1):31-8
references.pmid: 12564751
references.citation: Hear Res. 2005 May;203(1-2):134-43
references.pmid: 15855038
references.citation: Otol Neurotol. 2004 Mar;25(2):112-20
references.pmid: 15021769
references.citation: Int J Pediatr Otorhinolaryngol. 2002 Jun 17;64(2):111-25
references.pmid: 12049824
references.citation: Volta Rev. 2005 Spring;105(1):41-72
references.pmid: 21528108
references.citation: Cogn Psychol. 1989 Jan;21(1):60-99
references.pmid: 2920538
references.citation: Volta Rev. 2001;103(4):303-326
references.pmid: 21643556
references.citation: Brain Lang. 2003 Dec;87(3):369-84
references.pmid: 14642540
references.citation: J Speech Lang Hear Res. 2007 Aug;50(4):1048-62
references.pmid: 17675604
references.citation: Dev Sci. 2012 May;15(3):448-61
references.pmid: 22490184
references.citation: Brain Lang. 2004 Apr;89(1):115-21
references.pmid: 15010243