title: Sound envelope processing in the developing human brain: A MEG study.
abstract: OBJECTIVE
  This study investigated auditory cortical processing of linguistically-relevant temporal modulations in the developing brains of young children.
  
  
  METHODS
  Auditory envelope following responses to white noise amplitude modulated at rates of 1-80 Hz in healthy children (aged 3-5 years) and adults were recorded using a paediatric magnetoencephalography (MEG) system and a conventional MEG system, respectively.
  
  
  RESULTS
  For children, there were envelope following responses to slow modulations but no significant responses to rates higher than about 25 Hz, whereas adults showed significant envelope following responses to almost the entire range of stimulus rates.
  
  
  CONCLUSIONS
  Our results show that the auditory cortex of preschool-aged children has a sharply limited capacity to process rapid amplitude modulations in sounds, as compared to the auditory cortex of adults.
  
  
  CONCLUSIONS
  These neurophysiological results are consistent with previous psychophysical evidence for a protracted maturational time course for auditory temporal processing. The findings are also in good agreement with current linguistic theories that posit a perceptual bias for low frequency temporal information in speech during language acquisition. These insights also have clinical relevance for our understanding of language disorders that are associated with difficulties in processing temporal information in speech.
authors.affiliation: ARC Centre of Excellence in Cognition and its Disorders, Macquarie University, Sydney, NSW 2109, Australia; Department of Cognitive Science, Macquarie University, Sydney, NSW 2109, Australia. Electronic address: joann.tang@mq.edu.au.
authors.forename: Huizhen
authors.initials: H
authors.lastname: Tang
authors.affiliation: ARC Centre of Excellence in Cognition and its Disorders, Macquarie University, Sydney, NSW 2109, Australia; Department of Cognitive Science, Macquarie University, Sydney, NSW 2109, Australia.
authors.forename: Jon
authors.initials: J
authors.lastname: Brock
authors.affiliation: ARC Centre of Excellence in Cognition and its Disorders, Macquarie University, Sydney, NSW 2109, Australia; Department of Cognitive Science, Macquarie University, Sydney, NSW 2109, Australia.
authors.forename: Blake W
authors.initials: BW
authors.lastname: Johnson
mesh_terms: D000161:Acoustic Stimulation / Q000379:methods*; D000328:Adult; D001303:Auditory Cortex / Q000254:growth & development*; D001307:Auditory Perception / Q000502:physiology*; D002675:Child, Preschool; D005072:Evoked Potentials, Auditory / Q000502:physiology; D005260:Female; D006801:Humans; D015225:Magnetoencephalography / Q000379:methods*; D008297:Male; D013016:Sound; D055815:Young Adult
keywords: Auditory cortex; Auditory steady state response; Development; Envelope following response; Language acquisition; Temporal processing