The Full Wiki

Auditory processing disorder: Wikis

Advertisements
  
  

Note: Many of our articles have direct quotes from sources you can cite, within the Wikipedia article! This article doesn't yet, but we're working on it! See more info or our list of citable articles.

Encyclopedia

From Wikipedia, the free encyclopedia

Auditory processing disorder
Classification and external resources
ICD-9 315.32, 388.45
MeSH D001308

Auditory Processing Disorder (APD) (also known as (Central) Auditory Processing Disorder or (C)APD) is an umbrella term for a variety of disorders that affect the way the brain processes auditory information. It is not a sensory (inner ear) hearing impairment; individuals with APD usually have normal peripheral hearing ability.

Contents

Definitions

The American Speech-Language-Hearing Association (ASHA) published "(Central) Auditory Processing Disorders" in January 2005 as an update to the "Central Auditory Processing: Current Status of Research and Implications for Clinical Practice (ASHA, 1996)",[1] complementing the UK's Medical Research Council's Institute of Hearing Research's Auditory Processing Disorder (APD) pamphlet, Oct 2004.[2]

Auditory processing disorder can be congenital or acquired. It may result from ear infections, head injuries or developmental delays that cause central nervous system difficulties that affect processing of auditory information. This can include problems with: "...sound localization and lateralization; auditory discrimination; auditory pattern recognition; temporal aspects of audition, including temporal integration, temporal discrimination (e.g., temporal gap detection), temporal ordering, and temporal masking; auditory performance in competing acoustic signals (including dichotic listening); and auditory performance with degraded acoustic signals."[3]

The Committee of UK Medical Professionals Steering the UK Auditory Processing Disorder Research Program have developed the following working definition of Auditory Processing Disorder:

"APD results from impaired neural function and is characterized by poor recognition, discrimination, separation, grouping, localization, or ordering of non-speech sounds. It does not solely result from a deficit in general attention, language or other cognitive processes."[4]

Diagnosis

As APD is one of the more difficult information processing disorders to detect and diagnose, it may sometimes be misdiagnosed as ADD/ADHD, Asperger syndrome and other forms of autism, but it may also be a comorbid[5] aspect of those conditions if it is considered a significant part of the overall diagnostic picture. APD shares common symptoms in areas of overlap, such that professionals unfamiliar with APD might misdiagnose it as a condition they are aware of.

People with APD intermittently experience an inability to process verbal information. When people with APD have a processing failure, they do not process what is being said to them. They may be able to repeat the words back word for word, but the meaning of the message is lost. Simply repeating the instruction is of no use if a person with APD is not processing. Neither will increasing the volume help.

People with APD have a disorder processing auditory information within the brain. The written word is a visual notation of verbal language, thus Auditory Processing Disorder can extend into reading and writing.

There are also many other hidden implications, which are not always apparent even to the person with the disability. For example, because people with APD are used to guessing to fill in the processing gaps, they may not even be aware that they have misunderstood something.

APD has been defined anatomically in terms of the integrity of the auditory nervous system[6], as "what we do with what we hear",[7] and in terms of performances on a selected group of behavioral auditory tests (Task Force for the American Speech, Language, and Hearing Association; ASHA, 1994). The ASHA Task Force definition considered APD to be any observed deficits in one or more of these so-called "behaviors". Problems inherent in test validation by consensus are highlighted by the succession of task force reports that have appeared in recent years. The first of these occurred in 1996.[1] This was followed by a conference organized by the American Academy of Audiology[8] that explicitly embraced modality specificity as a defining characteristic of auditory processing disorders. Subsequently, an ASHA committee rejected modality specificity as a defining characteristic of auditory processing disorders.[9]

There have been several commentaries questioning various aspects of these proposals.[7][10][11] Additionally, Moore suggests that APD is primarily a difficulty in processing non-speech sounds and that a population-based approach should be taken to identify outlying performers.[11] However, inclusive conceptualizations of APD have been criticized based on their lack of diagnostic specificity.[12][13] Auditory processing disorder has been defined as a modality specific perceptual dysfunction that is not due to peripheral hearing loss.[10][14] This viewpoint emphasizes the perceptual nature of auditory processing and asserts that the disorder should be conceptualized as being limited to problems in processing auditory material. Numerous authors have suggested that existing tests of APD may be sensitive to factors that are not of an auditory perceptual nature.[15][16] Modality specificity has been advocated as a way to improve APD diagnosis.[10][14]

Causes

The causes of APD are unknown. There is anecdotal evidence to suggest links to autistic spectrum disorder, dyslexia, middle ear infections and lack of oxygen at birth, among other conditions.[citation needed]

Characteristics

Persons with APD often:[citation needed]

  • have trouble paying attention to and remembering information presented orally; they cope better with visually acquired information
  • may have trouble paying attention and remembering information when information is simultaneously presented in multiple modalities
  • have problems carrying out multi-step directions given orally; need to hear only one direction at a time
  • appear to have poor listening skills, and need people to speak slowly
  • need more time to process information.
  • develop a dislike for locations with background noise such as bar, clubs or other social locations
  • prefer written communication (e.g. text chat)
  • have behavioral problems.

APD can manifest as problems determining the direction of sounds, difficulty perceiving differences between speech sounds and the sequencing of these sounds into meaningful words, confusing similar sounds such as "hat" with "bat", "there" with "where", etc. Fewer words may be perceived than were actually said, as there can be problems detecting the gaps between words, creating the sense that someone is speaking unfamiliar or nonsense words. Those suffering from APD may have problems relating what has been said with its meaning, despite obvious recognition that a word has been said, as well as repetition of the word. Background noise, such as the sound of a radio, television or a noisy bar can make it difficult to impossible to understand speech, depending on the severity of the auditory processing disorder. Using a telephone can be problematic for someone with auditory processing disorder, in comparison with someone with normal auditory processing, due to low quality audio, poor signal, intermittent sounds and the chopping of words.[9] Many who have auditory processing disorder subconsciously develop visual coping strategies, such as lip reading, reading body language, and eye contact, to compensate for their auditory deficit, and these coping strategies are not available when using a telephone.

Advertisements

Secondary characteristics

Those who have APD tend to be quiet or shy,[citation needed] even withdrawn from mainstream society due to their communication problems, and the lack of understanding of these problems by their peers.

One who fails to process any part of the communication of others may be unable to comprehend what is being communicated. This has some obvious social and educational implication, which can cause a lack of understanding from others. In adults this can lead to persistent interpersonal relationship problems.

APD shares some of these signs with related disorders, which may have other overlap areas, such as acquired brain injury, attention deficits, dyslexia, learning difficulties, hearing loss, and psychologically-based behavioral problems.

APD may be related to cluttering,[17] a fluency disorder marked by word and phrase repetitions.

Remediations and training

Recent research has shown that practice with basic auditory processing tasks (i.e. auditory training) can improve performance on auditory processing measures (Chermak & Musiek, 2007) and phonemic awareness measures (Moore et al, 2005). These auditory training benefits have also been recorded at the physiological level (Russo et al, 2005; Alonso & Schochat, 2009). Many of these tasks are incorporated into computer based auditory training programs such as Earobics and Fast Forword.

There is no research supporting the following APD treatments:

  • Auditory Integration Training typically involves a child attending two 30-minute sessions per day for ten days.[18]
  • Lindamood-Bell Learning Processes (particularly, the Visualizing and Verbalizing program)
  • Physical activities that require frequent crossing of the midline (e.g., occupational therapy)
  • Sound Field Amplification

Relation to Specific language impairment

APD can also be confused with Specific language impairment (SLI).

SLI is more specifically a problem associated with the linking of words, both written and spoken, to semantics (meaning) and someone can have both APD and SLI. Unlike those with SLI, those with APD can usually get the meaning of language from written words where those with SLI show problems with both heard and read words, demonstrating that the basic issue is not an auditory one.

Those with APD have auditory difficulty distinguishing sounds including speech from extraneous sounds, e.g. fans or other chatter. APD is purely about processing what you hear both verbal and non-verbal. For those who have APD, difficulty processing verbal language is only one of many symptoms.

See also

References

  1. ^ a b "Central Auditory Processing: Current Status of Research and Implications for Clinical Practice. Technical Report, (1996)". Working Group on Auditory Processing Disorders. American Speech-Language-Hearing Association. http://www.asha.org/docs/html/TR1996-00241.html. 
  2. ^ "Auditory Processing Disorder (APD). Pamphlet, (2004).". British Society of Audiology APD Special Interest Group. MRC Institute of Hearing Research. http://www.ihr.mrc.ac.uk/research/apd.php/apd.php?page=apd_docs. Retrieved 2008-01-15. 
  3. ^ (Central) Auditory Processing Disorders, Technical Report, Jan 2005)
  4. ^ http://www.thebsa.org.uk/apd/Home.htm The British Society of Audiology and the UK APD Steering Group
  5. ^ http://www.tsbvi.edu/Outreach/seehear/spring00/centralauditory.htm
  6. ^ Rintelmann, W.F. (1985). Monaural speech tests in the detection of central auditory disorders. In M.L. Pinheiro, & F.E. Musiek (Eds.), Assessment of central auditory dysfunction: foundations and clinical correlates (pp. 173-200). Baltimore: Williams & Wilkens
  7. ^ a b Katz, J. (1992). Classification of auditory processing disorders. In J. Katz, N. Stecker, D. Henderson (Eds.), Central Auditory Processing: A Transdisciplinary View (p. 81-92). Chicago: Mosby Yearbook.
  8. ^ Jerger, J, Musiek, F (2000) Report of the Consensus Conference in the diagnosis of auditory processing disorders in school-aged children. Journal of the American Academy of Audiology, 11, 467-474.
  9. ^ a b "(Central) Auditory Processing Disorders. Technical Report, (2005).". Working Group on Auditory Processing Disorders.. American Speech-Language-Hearing Association.. http://www.asha.org/docs/html/TR2005-00043.html. 
  10. ^ a b c Cacace, AT and McFarland, DJ (2005) The importance of modality specificity in diagnosing central auditory processing disorder. American Journal of Audiology, 14: 112-123.
  11. ^ a b Moore DR (2006). Auditory processing disorder (APD): Definition, diagnosis, neural basis, and intervention. Audiological Medicine, 4, p4-11
  12. ^ Rees, N.: Auditory processing factors in language disorders: The view from Procrustes' bed. Journal of Speech and Hearing Disorders, 1973, 38, 304–315
  13. ^ Cacace A T; McFarland D J, Central auditory processing disorder in school-aged children: a critical review. Journal of speech, language, and hearing research : JSLHR 1998;41(2):355-73.
  14. ^ a b Cacace, Anthony T., McFarland, Dennis J. Opening Pandora's Box: The Reliability of CAPD Tests Am J Audiol 1995 4: 61-62
  15. ^ Friel-Patti, S. (1999) Clinical decision-making in the assessment and intervention of central auditory processing disorders. “Language, Speech, and Hearing Services in the Schools”, 30, 345-352
  16. ^ Grundast, K.M, Berkowiitz, R.G, Connerss, C.K.,and Bellman, P. (191) Complete evaluation of the child identified as a poor listener. “International Journal of Pediatric Otorhinolarynglogy”, 21, 65-78.
  17. ^ William O. Haynes, Rebekah Hand Pindzola, Michael J. Moran, Communication Disorders in the Classroom: An Introduction for Professionals in School Settings, ISBN 0763727431, Jones & Bartlett Publishers (2006), p. 251
  18. ^ Mudford OC, Cullen C (2004). "Auditory integration training: a critical review". in Jacobson JW, Foxx RM, Mulick JA (eds.). Controversial Therapies for Developmental Disabilities. Routledge. pp. 351–62. ISBN 080584192X. 

External links


Advertisements






Got something to say? Make a comment.
Your name
Your email address
Message