title: Event-related potentials to pitch and rise time change in children with reading disabilities and typically reading children.
abstract: OBJECTIVE
  The purpose of the present study was to investigate whether children with reading disabilities (RD) process rise time and pitch changes differently to control children as a function of the interval between two tones.
  
  
  METHODS
  Children participated in passive oddball event-related potential (ERP) measurements using paired stimuli. Mismatch negativity (MMN), P3a and late discriminative negativity (LDN) responses to rise time and pitch changes were examined.
  
  
  RESULTS
  Control children produced larger responses than children with RD to pitch change in the P3a component but only when the sounds in the pair were close to each other. Compared to children with RD, MMN was smaller and LDN larger in control children in response to rise time change when the sounds in the pair were further apart. The non-overlap in ERP measures between the groups was 40-50%.
  
  
  CONCLUSIONS
  Problems in rapid processing of pitch change were reflected in a component associated with attention switching while amplitude envelope processing problems were reflected in components associated with stimulus detection or discrimination.
  
  
  CONCLUSIONS
  Children with RD process both rise time and pitch changes differently from control children thus providing evidence for the nature of amplitude envelope processing and rapid auditory processing deficits in dyslexia.
authors.affiliation: Department of Psychology, University of Jyväskylä, PO Box 35, Agora, 40014 Jyväskylä, Finland. jarmo.hamalainen@psyka.jyu.fi
authors.forename: J A
authors.initials: JA
authors.lastname: Hämäläinen
authors.forename: P H T
authors.initials: PH
authors.lastname: Leppänen
authors.forename: T K
authors.initials: TK
authors.lastname: Guttorm
authors.forename: H
authors.initials: H
authors.lastname: Lyytinen
mesh_terms: D000161:Acoustic Stimulation / Q000379:methods; D001931:Brain Mapping; D002648:Child; D003265:Contingent Negative Variation / Q000502:physiology*; D004410:Dyslexia / Q000503:physiopathology*; D004569:Electroencephalography; D005072:Evoked Potentials, Auditory / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D015999:Multivariate Analysis; D009483:Neuropsychological Tests; D010897:Pitch Discrimination / Q000502:physiology*; D011930:Reaction Time / Q000502:physiology*; D011932:Reading; D013997:Time Factors