title: Auditory-cognitive interactions underlying interaural asymmetry in an adult listener: a case study.
abstract: OBJECTIVE
  Abnormal interaural asymmetry on tests of dichotic listening is commonly observed in individuals suspected of auditory processing disorder (APD). Although a structural basis for the abnormality has been widely accepted, the influence of cognitive variables on the degree of observed asymmetry has gained increasing attention. To study this issue, we manipulated cognitive influences on interaural asymmetry in an adult with the auditory complaints typically associated with APD.
  
  
  METHODS
  A 55 year-old woman with complaints of difficulty understanding speech in noisy environments despite normal audiometric levels.
  
  
  METHODS
  Several experimental dichotic procedures were administered. Each procedure was characterized by the manipulation of cognitive task demands.
  
  
  RESULTS
  Interaural asymmetry was greatest when the demands on attention and/or memory were maximal. Electrophysiological data revealed interaural asymmetry on later stages of information processing.
  
  
  CONCLUSIONS
  Results are discussed in relation to auditory-specific outcomes on clinical tests for APD.
authors: Department of Speech Pathology and Audiology, University of South Alabama, Mobile, Alabama 36688-0002, USA. taradavis@usouthal.edu
authors: Tara
authors: T
authors: Davis
authors: Jeffrey
authors: J
authors: Martin
authors: James
authors: J
authors: Jerger
authors: Ralf
authors: R
authors: Greenwald
authors: Jyutika
authors: J
authors: Mehta
mesh_terms: D000161:Acoustic Stimulation; D001302:Audiometry, Speech; D001308:Auditory Perceptual Disorders / Q000175:diagnosis / Q000523:psychology*; D001309:Auditory Threshold; D003071:Cognition; D032882:Comprehension; D004007:Dichotic Listening Tests; D004569:Electroencephalography; D016057:Evoked Potentials, Auditory, Brain Stem; D005260:Female; D007839:Functional Laterality; D006801:Humans; D008875:Middle Aged; D009622:Noise / Q000009:adverse effects*; D017084:Otoacoustic Emissions, Spontaneous; D010470:Perceptual Masking; D011571:Psychoacoustics; D013065:Speech Intelligibility; D013067:Speech Perception; D014888:Wechsler Scales