DIAGNOSIS AND MANAGEMENT
CENTRAL AUDITORY PROCESSING DISORDER
Part I: Definition
Gail D. Chermak, Ph.D.
Washington State University
The brief article below is
the first installment of a three part series of brief articles by Dr. Chermak
on central auditory processing disorder.
Notwithstanding the primacy of auditory processing deficits in central auditory
processing disorders (CAPD), it is a complex and heterogeneous group of disorders
usually associated with a range of listening and learning deficits (ASHA, 1996;
Chermak & Musiek, 1992, 1997). CAPD "refers to a deficit observed in
one or more of the central auditory processes responsible for generating the
auditory evoked potentials and the following behaviors: sound localization and
lateralization; auditory discrimination; auditory pattern recognition; temporal
aspects of audition including, temporal resolution, temporal masking, temporal
integration, and temporal ordering; auditory performance with competing acoustic
signals; and auditory performance with degraded acoustic signals." (Chermak
& Musiek, 1997, p. 3).
CAPD may be broadly defined
as an auditory specific deficit in the processing of information, which may
be associated with difficulties in listening, speech understanding, language
development and learning. These clinical linkages occur because all auditory
tasks, from pure tone perception to spoken language processing, are influenced
by higher-level, non-modality specific factors such as attention, learning,
motivation and decision processes. Central auditory processes involve the deployment
of non-dedicated, global mechanisms of attention and memory in service of acoustic
CAPD has been observed
in a variety of clinical populations, including those associated with known
lesions or pathology of the central nervous system (e.g., aphasia, Alzheimer's
disease, traumatic brain injury) and others with suspected but unconfirmed
central nervous system pathology or neurodevelopmental disorder (e.g., developmental
language disorder, dyslexia, learning disabilities, attention deficit disorder).
It has been reported in association with a history of chronic otitis media
(i.e., middle ear infection) and has been documented in older adults due to
neurologic changes resulting from the aging process. The overlapping symptomatology
across these diverse clinical populations and the range of listening and learning
deficits associated with this complex and heterogeneous group of disorders,
demands careful assessment and comprehensive intervention, both of which are
discussed in subsequent sections of this series.
Visit the American
Academy of Audiology and the American
Speech-Language-Hearing Association web sites for additional information
and/or to locate an audiologist or speech-language pathologist in your area.
Academy of Audiology
8300 Greensboro Dr., Suite 750
McLean, Virginia 22102
10801 Rockville Pike
Rockville, Maryland 20852
Gail D. Chermak Ph. D.,
is an Edward R. Meyer Distinguished Professor of Audiology and Chair of the
Department of Speech and Hearing Sciences at Washington State University. She
earned her doctorate in speech and hearing sciences from the Ohio State University,
holds the Certificate of Clinical Competence in Audiology, and is a fellow of
the American Academy of Audiology.
Dr. Chermak chaired the
ASHA Ad Hoc Committee on Central Auditory Processing which prepared the 1992
report entitled, Issues in Central Auditory Processing Disorders. She served
as a member of the ASHA Task Force on Central Auditory Processing Consensus
Development responsible for the 1995 report, Central Auditory Processing: Current
Status of Research and Implications for Clinical Practice. She was among 14
senior scientists and clinicians who met recently at the University of Texas
at Dallas (the Bruton Conference) to reach consensus on best practices in diagnosis
of auditory processing problems in school-age children.
Dr. Chermak has published
articles and delivered numerous workshops on assessment and management of central
auditory processing disorders. Her co-authored articles on central auditory
processing disorder and attention deficit hyperactivity disorder have been named
by her peers as among the best in diagnostic audiology for the past two consecutive
years. Her 1997 book, Central
Auditory Processing Disorders: New Perspectives, co-authored with Frank
Musiek and published by Singular Publishing Group, has become a landmark volume
in the field.