title: Auditory perception in individuals with Friedreich's ataxia.
abstract: BACKGROUND
  Friedreich's ataxia (FRDA) is an inherited ataxia with a range of progressive features including axonal degeneration of sensory nerves. The aim of this study was to investigate auditory perception in affected individuals.
  
  
  METHODS
  Fourteen subjects with genetically defined FRDA participated. Two control groups, one consisting of healthy, normally hearing individuals and another comprised of subjects with sensorineural hearing loss, were also assessed. Auditory processing was evaluated using structured tasks designed to reveal the listeners' ability to perceive temporal and spectral cues. Findings were then correlated with open-set speech understanding.
  
  
  RESULTS
  Nine of 14 individuals with FRDA showed evidence of auditory processing disorder. Gap and amplitude modulation detection levels in these subjects were significantly elevated, indicating impaired encoding of rapid signal changes. Electrophysiologic findings (auditory brainstem response, ABR) also reflected disrupted neural activity. Speech understanding was significantly affected in these listeners and the degree of disruption was related to temporal processing ability. Speech analyses indicated that timing cues (notably consonant voice onset time and vowel duration) were most affected.
  
  
  CONCLUSIONS
  The results suggest that auditory pathway abnormality is a relatively common consequence of FRDA. Regular auditory evaluation should therefore be part of the management regime for all affected individuals. This assessment should include both ABR testing, which can provide insights into the degree to which auditory neural activity is disrupted, and some functional measure of hearing capacity such as speech perception assessment, which can quantify the disorder and provide a basis for intervention.
authors.affiliation: Department of Otolaryngology, The University of Melbourne, Parkville, Vic., Australia. grance@unimelb.edu.au
authors.forename: Gary
authors.initials: G
authors.lastname: Rance
authors.forename: Louise
authors.initials: L
authors.lastname: Corben
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Barker
authors.forename: Peter
authors.initials: P
authors.lastname: Carew
authors.forename: Donella
authors.initials: D
authors.lastname: Chisari
authors.forename: Meghan
authors.initials: M
authors.lastname: Rogers
authors.forename: Richard
authors.initials: R
authors.lastname: Dowell
authors.forename: Saiful
authors.initials: S
authors.lastname: Jamaluddin
authors.forename: Rochelle
authors.initials: R
authors.lastname: Bryson
authors.forename: Martin B
authors.initials: MB
authors.lastname: Delatycki
mesh_terms: D000161:Acoustic Stimulation; D000293:Adolescent; D000328:Adult; D001306:Auditory Pathways / Q000503:physiopathology; D001308:Auditory Perceptual Disorders / Q000175:diagnosis* / Q000235:genetics / Q000503:physiopathology; D001933:Brain Stem / Q000503:physiopathology; D015331:Cohort Studies; D003463:Cues; D016057:Evoked Potentials, Auditory, Brain Stem / Q000235:genetics / Q000502:physiology; D005260:Female; D005621:Friedreich Ataxia / Q000175:diagnosis* / Q000235:genetics / Q000503:physiopathology; D006319:Hearing Loss, Sensorineural / Q000175:diagnosis / Q000235:genetics / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D010700:Phonetics; D010898:Pitch Perception; D012016:Reference Values; D013018:Sound Spectrography; D013061:Speech Acoustics; D013067:Speech Perception / Q000235:genetics / Q000502:physiology; D013998:Time Perception; D055815:Young Adult