Auditory processing disorder

Individuals with this disorderNational Center for Learning Disabilities | NCLD.org – NCLD. National Center for Learning Disabilities | NCLD.org – NCLD. N.p., n.d. Web. 19 November 2014. may experience the following signs and symptoms:{{Cite journal |last1=Bamiou |first1=D.-E. |last2=Musiek |first2=F. E. |last3=Luxon |first3=L. M. |date=2001-11-01 |title=Aetiology and clinical presentations of auditory processing disorders—a review |url=https://adc.bmj.com/content/85/5/361 |journal=Archives of Disease in Childhood |language=en |volume=85 |issue=5 |pages=361–365 |doi=10.1136/adc.85.5.361 |issn=0003-9888 |pmid=11668093|pmc=1718975 }}

• speaking louder or softer than is situationally appropriate;
• difficulty remembering lists or sequences;
• needing words or sentences to be repeated;
• impaired ability to memorize information learned by listening;
• interpreting words too literally;
• needing assistance to hear clearly in noisy environments;
• relying on accommodation and modification strategies;
• finding or requesting a quiet work space away from others;
• requesting written material when attending oral presentations; and
• asking for directions to be given one step at a time.

APD and attention deficit hyperactivity disorder (ADHD) can present with overlapping symptoms. Below is a ranked order of behavioral symptoms that are most frequently observed in each disorder. Professionals evaluated the overlap of symptoms between the two disorders, note the order of symptoms that are almost always observed.{{cite journal|last1=Chermak|first1=Gail D.|last2=Somers|first2=Erin K.|last3=Seikel|first3=J. Anthony|title=Behavioral signs of central auditory processing disorder and attention deficit hyperactivity disorder|journal=Journal of American Academy of Audiology|volume=9|issue=1|date=1998|pages=78–84|pmid=9493945}} Although the symptoms listed have differences, their similar presentation in individuals often makes it difficult to differentiate between the two conditions.{{Cite journal |last1=de Wit |first1=Ellen |last2=van Dijk |first2=Pim |last3=Hanekamp |first3=Sandra |last4=Visser-Bochane |first4=Margot I. |last5=Steenbergen |first5=Bert |last6=van der Schans |first6=Cees P. |last7=Luinge |first7=Margreet R. |date=January 2018 |title=Same or Different: The Overlap Between Children With Auditory Processing Disorders and Children With Other Developmental Disorders: A Systematic Review |journal=Ear and Hearing |volume=39 |issue=1 |pages=1–19 |doi=10.1097/AUD.0000000000000479 |issn=0196-0202 |pmc=7654752 |pmid=28863035}}

There is a co-occurrence between ADHD and APD. A systematic review published in 2018{{cite journal |last1=de Wit |first1=Ellen |last2=van Dijk |first2=Pim |last3=Hanekamp |first3=Sandra |last4=Visser-Bochane |first4=Margot I. |last5=Steenbergen |first5=Bert |last6=van der Schans |first6=Cees P. |last7=Luinge |first7=Margreet R. |title=Same or Different: The Overlap Between Children With Auditory Processing Disorders and Children With Other Developmental Disorders: A Systematic Review |journal=Ear and Hearing |date=2018 |volume=39 |issue=1 |pages=1–19 |doi=10.1097/AUD.0000000000000479 |pmid=28863035 |pmc=7654752 |url=}} detailed one study that showed 10% of children with APD have confirmed or suspected ADHD. It also stated that it is sometimes difficult to distinguish the two, since characteristics and symptoms between APD and ADHD tend to overlap. The systematic review also described this overlap between APD and other behavioral disorders and whether or not it was easy to distinguish those children that solely had auditory processing disorder.{{citation needed|date=December 2020}}

There has been considerable debate over the relationship between APD and developmental language disorder (DLD), previously called specific language impairment (SLI).

SLI is diagnosed when a child has difficulties with understanding or producing spoken language, and the cause of these difficulties is not obvious (and specifically cannot be explained by peripheral hearing loss). The child is typically late in their language development and may struggle to produce clear speech sounds and produce or understand complex sentences. Some theorize that SLI is the result of auditory processing problems.{{cite journal|last=Miller|first=C. A.|s2cid=17500092|year=2011|title= Auditory processing theories of language disorders: Past, present, and future.|journal=Language, Speech, and Hearing Services in Schools|volume=42|issue=3|pages=309–319|doi= 10.1044/0161-1461(2011/10-0040)|pmid=21757567}}{{cite journal|last1=Ferguson|first1= M. A.|last2=Hall|first2=R. L.|last3= Riley|first3=A|last4= Moore|first4= D. R.|year=2011|title=Communication, listening, cognitive and speech perception skills in children with auditory processing disorder (APD) or specific language impairment (SLI)|journal=Journal of Speech, Language, and Hearing Research|volume= 54|issue=1|pages=211–227| doi=10.1044/1092-4388(2010/09-0167)|pmid= 20689032}} However, this theory is not universally accepted; others theorize that the main difficulties associated with SLI stem from problems with the higher-level aspects of language processing. Where a child has both auditory and language problems, it can be difficult to sort out the causality at play.

Similarly with developmental dyslexia, researchers continue to explore the hypothesis that reading problems emerge as a downstream consequence of difficulties in rapid auditory processing. Again, cause and effect can be hard to unravel. This is one reason why some experts have recommended using non-verbal auditory tests to diagnose APD. Specifically regarding neurological factors, dyslexia has been linked to polymicrogyria which causes cell migrational problems. Children that have polymicrogyri almost always present with deficits on APD testing.{{cite book|last1=Chermak|first1=Gail|last2=Musiek|first2=Frank|title=Handbook of central auditory processing disorder. comprehensive intervention|date=2014|publisher=Plural Publishing|location=San Diego, CA|isbn=978-1-59756-562-2|edition=2}} It has also been suggested that APD may be related to cluttering,{{cite book |author1=Pindzola, Rebekah H. |author2=Haynes, William O. |author3=Moran, Michael J. |title=Communication disorders in the classroom: an introduction for professionals in school setting |publisher=Jones and Bartlett Publishers |location=Boston |year=2006 |page=251 |isbn=978-0-7637-2743-7 |oclc=59401841 }} a fluency disorder marked by word and phrase repetitions.

Some studies found that a higher than expected proportion of individuals diagnosed with SLI and dyslexia on the basis of language and reading tests also perform poorly on tests in which auditory processing skills are tested.{{cite journal|last1=Moore|first1=David R.|title=Auditory processing disorders: Acquisition and treatment|journal=Journal of Communication Disorders|date=July 2007|volume=40|issue=4|pages=295–304|doi=10.1016/j.jcomdis.2007.03.005|pmid=17467002}}{{cite journal |last1=Kalaiah |first1=Mohan |date=2015 |title=Relation between phonological processing, auditory processing and speech perception among bilingual poor readers |url= |journal=Korean Journal of Audiology |volume=19 |issue=3 |pages=125–131 |doi=10.7874/jao.2015.19.3.125 |pmc= 4704549|pmid= 26771010|s2cid=488841 |name-list-style=vanc}} APD can be assessed using tests that involve identifying, repeating, or discriminating speech, and a child may perform poorly because of primary language problems. In a study comparing children with a diagnosis of dyslexia and those with a diagnosis of APD, they found the two groups could not be distinguished.{{cite journal|last1=Dawes|first1=P|last2=Bishop|first2= D|year=2010|title=Psychometric profile of children with auditory processing disorder (APD) and children with dyslexia|journal=Archives of Disease in Childhood|volume=95|issue=6|pages=432–436|doi=10.1136/adc.2009.170118|pmid=20501538|pmc=3576918}}

{{cite journal |last1=Miller|first1= C.A.|last2=Wagstaff|first2=D.A.|year=2011 |title=Behavioral profiles associated with auditory processing disorder and specific language impairment.|journal=Journal of Communication Disorders|volume=44|issue=6|pages=745–763 |doi=10.1016/j.jcomdis.2011.04.001|pmid= 21636094|pmc=3174343}} Analogous results were observed in studies comparing children diagnosed with SLI or APD, the two groups presenting with similar diagnostic criteria.{{cite journal |vauthors=Corriveau K, Pasquini E, Goswami U |s2cid=1074440 |title=Basic auditory processing skills and specific language impairment: a new look at an old hypothesis |journal=J. Speech Lang. Hear. Res. |volume=50 |issue=3 |pages=647–66 |date=June 2007 |pmid=17538107 |doi=10.1044/1092-4388(2007/046) }}{{cite journal |vauthors=Dlouha O, Novak A, Vokral J |title=Central auditory processing disorder (CAPD) in children with specific language impairment (SLI). Central auditory tests |journal=Int. J. Pediatr. Otorhinolaryngol. |volume=71 |issue=6 |pages=903–7 |date=June 2007 |pmid=17382411 |doi=10.1016/j.ijporl.2007.02.012 }} As such, the diagnosis a child receives may depend on which specialist they consult: the same child who might be diagnosed with APD by an audiologist may instead be diagnosed with SLI by a speech-language therapist, or with dyslexia by a psychologist.

Acquired APD can be caused by any damage to, or dysfunction of, the central auditory nervous system and can cause auditory processing problems.{{cite journal |vauthors=Musiek FE, Chermak GD, Weihing J, Zappulla M, Nagle S |title=Diagnostic accuracy of established central auditory processing test batteries in patients with documented brain lesions |journal=J Am Acad Audiol |volume=22 |issue=6 |pages=342–58 |date=June 2011 |pmid=21864472 |doi=10.3766/jaaa.22.6.4 }}{{cite journal |vauthors=Lew HL, Weihing J, Myers PJ, Pogoda TK, Goodrich GL |title=Dual sensory impairment (DSI) in traumatic brain injury (TBI)--An emerging interdisciplinary challenge |journal=NeuroRehabilitation |volume=26 |issue=3 |pages=213–22 |year=2010 |pmid=20448311 |doi=10.3233/NRE-2010-0557 }} For an overview of neurological aspects of APD, see T. D. Griffiths's 2002 article "Central Auditory Pathologies".{{cite journal|last=Griffiths|first=T. D.|year=2002|title=Central auditory pathologies. |journal=British Medical Bulletin|volume=63|issue=1|pages=107–120| doi=10.1093/bmb/63.1.107|pmid=12324387|doi-access=free}}

Some studies have indicated an increased prevalence of a family history of hearing impairment in these patients. The pattern of results is suggestive that auditory processing disorder may be related to conditions of autosomal dominant inheritance.{{cite journal |vauthors=Stephens D, Zhao F |s2cid=45623565 |title=The role of a family history in King Kopetzky Syndrome (obscure auditory dysfunction) |journal=Acta Otolaryngol. |volume=120 |issue=2 |pages=197–200 |date=March 2000 |pmid=11603771 |doi=10.1080/000164800750000900 }}{{cite journal |vauthors=Liu XZ, Xu L, Newton V |title=Audiometric configuration in non-syndromic genetic hearing loss |journal=J Audiol Med |volume=3 |pages=99–106 }}{{cite journal |vauthors=Van Camp G, Willems PJ, Smith RJ |title=Non-syndromic hearing impairment: unparalleled heterogeneity |journal=Am J Genet |volume=60 |pages=758–64 |year=1997}} In other words, the ability to listen to and comprehend multiple messages at the same time is a trait that is heavily influenced by genes.("Genetics Influence Auditory Processing." Psych Central.com. N.p., n.d. Web. 2 December 2014.) These "short circuits in the wiring" sometimes run in families or result from a difficult birth, just like any learning disability.(NCLD.org – NCLD." National Center for Learning Disabilities | NCLD.org.) Inheritance of auditory processing disorder refers to whether an individual inherits the condition from their parents, or whether it runs in families.("Inheritance and Genetics of Auditory Processing Disorder." – RightDiagnosis.com. N.p., n.d. Web. 2 December 2014.) Central auditory processing disorder may be hereditary neurological traits from the mother or the father.{{cite journal | vauthors = Brewer CC, Zalewski CK, King KA | title = Heritability of non-speech auditory processing skills

| journal = European Journal of Human Genetics

| publisher = Eur J Hum Genet. | date=10 May 2020 | volume = 24 | issue = 8 | pages = 1137–1144

| doi=10.1038/ejhg.2015.277 | pmid = 26883091| pmc = 4872837

}}

In the majority of cases of developmental APD, the cause is unknown. An exception is acquired epileptic aphasia or Landau–Kleffner syndrome, where a child's development regresses, with language comprehension severely affected.{{cite journal |vauthors=Fandiño M, Connolly M, Usher L, Palm S, Kozak FK |title=Landau-Kleffner syndrome: a rare auditory processing disorder series of cases and review of the literature |journal=Int. J. Pediatr. Otorhinolaryngol. |volume=75 |issue=1 |pages=33–8 |date=January 2011 |pmid=21074868 |doi=10.1016/j.ijporl.2010.10.001 }} The child is often thought to be deaf, but testing reveals normal peripheral hearing. In other cases, suspected or known causes of APD in children include delay in myelin maturation,{{cite book |author1=Weihing, Jeff |author2=Musiek, Frank |chapter=15 Dichotic Interaural Intensity Difference (DIID) |title=Auditory Processing Disorders: Assessment, Management and Treatment |editor=Ross-Swain, Deborah |editor2=Geffner, Donna S |publisher=Plural Publishing Inc |year=2007 |isbn=978-1-59756-107-5 |oclc=255602759 }} ectopic (misplaced) cells in the auditory cortical areas,{{cite journal |vauthors=Boscariol M, Garcia VL, Guimarães CA |s2cid=6078682 |title=Auditory processing disorder in perisylvian syndrome |journal=Brain Dev. |volume=32 |issue=4 |pages=299–304 |date=April 2010 |pmid=19410403 |doi=10.1016/j.braindev.2009.04.002 |display-authors=etal}} or genetic predisposition.{{cite journal |vauthors=Bamiou DE, Campbell NG, Musiek FE |s2cid=45483072 |title=Auditory and verbal working memory deficits in a child with congenital aniridia due to a PAX6 mutation |journal=Int J Audiol |volume=46 |issue=4 |pages=196–202 |date=April 2007 |pmid=17454233 |doi=10.1080/14992020601175952 |display-authors=etal}} In one family with autosomal dominant epilepsy, seizures which affected the left temporal lobe seemed to cause problems with auditory processing.{{cite journal |vauthors=Pisano T, Marini C, Brovedani P, Brizzolara D, Pruna D, Mei D, Moro F, Cianchetti C, Guerrini R |title=Abnormal phonologic processing in familial lateral temporal lobe epilepsy due to a new LGI1 mutation |journal=Epilepsia |volume=46 |issue=1 |pages=118–23 |date=January 2005 |pmid=15660777 |doi=10.1111/j.0013-9580.2005.26304.x |s2cid=19751059 |doi-access=free }} In another extended family with a high rate of APD, genetic analysis showed a haplotype in chromosome 12 that fully co-segregated with language impairment.{{cite journal |vauthors=Addis L, Friederici AD, Kotz SA, Sabisch B, Barry J, Richter N, Ludwig AA, Rübsamen R, Albert FW, Pääbo S, Newbury DF, Monaco AP |title=A locus for an auditory processing deficit and language impairment in an extended pedigree maps to 12p13.31-q14.3 |journal=Genes, Brain and Behavior |volume=9 |issue=6 |pages=545–61 |date=August 2010 |pmid=20345892 |pmc=2948670 |doi=10.1111/j.1601-183X.2010.00583.x }}

Hearing begins in utero, but the central auditory system continues to develop for at least the first decade after birth.{{cite journal |author=Moore DR |title=Auditory development and the role of experience |journal=British Medical Bulletin |volume=63 |pages=171–81 |year=2002 |pmid=12324392 |doi= 10.1093/bmb/63.1.171|doi-access=free }} There is considerable interest in the idea that disruption to hearing during a sensitive period may have long-term consequences for auditory development.{{cite journal |vauthors=Thai-Van H, Veuillet E, Norena A, Guiraud J, Collet L |s2cid=27423669 |title=Plasticity of tonotopic maps in humans: influence of hearing loss, hearing aids and cochlear implants |journal=Acta Otolaryngol. |volume=130 |issue=3 |pages=333–7 |date=March 2010 |pmid=19845491 |doi=10.3109/00016480903258024 }} One study showed thalamocortical connectivity in vitro was associated with a time sensitive developmental window and required a specific cell adhesion molecule (lcam5) for proper brain plasticity to occur.{{cite journal |vauthors=Barkat TR, Polley DB, Hensch TK |title=A critical period for auditory thalamocortical connectivity |journal=Nature Neuroscience |volume=14 |issue=9 |pages=1189–94 |date=September 2011 |pmid=21804538 |doi=10.1038/nn.2882 |pmc=3419581}} This points to connectivity between the thalamus and cortex shortly after being able to hear (in vitro) as at least one critical period for auditory processing. Another study showed that rats reared in a single tone environment during critical periods of development had permanently impaired auditory processing.{{cite journal |vauthors=Han YK, Köver H, Insanally MN, Semerdjian JH, Bao S |s2cid=11772101 |title=Early experience impairs perceptual discrimination |journal=Nature Neuroscience |volume=10 |issue=9 |pages=1191–7 |date=September 2007 |pmid=17660815 |doi=10.1038/nn1941 }} In rats, "bad" auditory experiences, such as temporary deafness by cochlear removal, leads to neuron shrinkage. In a study looking at attention in APD patients, children with one ear blocked developed a strong right-ear advantage but were not able to modulate that advantage during directed-attention tasks.{{cite journal |vauthors=Asbjørnsen A, Holmefjord A, Reisaeter S, Møller P, Klausen O, Prytz B, Boliek C, Obrzut JE |s2cid=77979 |title=Lasting auditory attention impairment after persistent middle ear infections: a dichotic listening study |journal=Developmental Medicine and Child Neurology |volume=42 |issue=7 |pages=481–6 |date=July 2000 |pmid=10972421 |doi= 10.1111/j.1469-8749.2000.tb00352.x|doi-access=free }}

In the 1980s and 1990s, there was considerable interest in the role of chronic otitis media (also called middle ear disease or "glue ear") in causing APD and related language and literacy problems. Otitis media with effusion is a very common childhood disease that causes a fluctuating conductive hearing loss, and there was concern this may disrupt auditory development if it occurred during a sensitive period.{{cite journal |vauthors=Whitton JP, Polley DB |title=Evaluating the perceptual and pathophysiological consequences of auditory deprivation in early postnatal life: a comparison of basic and clinical studies |journal=J. Assoc. Res. Otolaryngol. |volume=12 |issue=5 |pages=535–47 |date=October 2011 |pmid=21607783 |doi=10.1007/s10162-011-0271-6 |pmc=3173557}} Consistent with this, in a sample of young children with chronic ear infections recruited from a hospital otorhinolaryngology department, increased rates of auditory difficulties were found later in childhood.{{cite journal |vauthors=Hartley DE, Moore DR |title=Effects of otitis media with effusion on auditory temporal resolution |journal=International Journal of Pediatric Otorhinolaryngology |volume=69 |issue=6 |pages=757–69 |date=June 2005 |pmid=15885328 |doi=10.1016/j.ijporl.2005.01.009}} However, this kind of study will have sampling bias because children with otitis media will be more likely to be referred to hospital departments if they are experiencing developmental difficulties. Compared with hospital studies, epidemiological studies, which assesses a whole population for otitis media and then evaluate outcomes, found much weaker evidence for long-term impacts of otitis media on language outcomes.{{cite journal|last1=Feldman|first1=H.M.|year=2003|title=Parent-reported language skills in relation to otitis media during the first 3 years of life|journal=Journal of Speech, Language, and Hearing Research|volume=46|issue=2|pages=273–287|doi=10.1044/1092-4388(2003/022)|pmid=14700371|display-authors=etal}}

It seems that somatic anxiety (that is, physical symptoms of anxiety such as butterflies in the stomach or cotton mouth) and situations of stress may be determinants of speech-hearing disability.{{cite journal |vauthors=Zhao F, Stephens D |title=Determinants of speech-hearing disability in King-Kopetzky syndrome |journal=Scand Audiol |volume=25 |issue=2 |pages=91–6 |year=1996 |pmid=8738633 |doi=10.3109/01050399609047989 }}{{cite journal |vauthors=King K, Stephens D |title=Auditory and psychological factors in 'auditory disability with normal hearing' |journal=Scand Audiol |volume=21 |issue=2 |pages=109–14 |year=1992 |pmid=1641572 |doi=10.3109/01050399209045990 }}

Questionnaires which address common listening problems can be used to identify individuals who may have auditory processing disorder, and can help in the decision to pursue clinical evaluation.

One of the most common listening problems is speech recognition in the presence of background noise.{{cite journal |last1=Jerger |first1=James |last2=Musiek |first2=Frank |title=Report of the Consensus Conference on the Diagnosis of Auditory Processing Disorders in School-Aged Children. |journal=Journal of the American Academy of Audiology |date=October 2000 |volume=11 |issue=9 |pages=467–74 |doi=10.1055/s-0042-1748136 |pmid=11057730 |s2cid=18887683 |url=https://www.audiology.org/sites/default/files/journal/JAAA_11_09_01.pdf |access-date=2018-10-21 |archive-date=2017-08-29 |archive-url=https://web.archive.org/web/20170829093120/https://www.audiology.org/sites/default/files/journal/JAAA_11_09_01.pdf }}{{cite journal|url=https://www.asha.org/policy/PS2005-00114/|author1=Working Group on Auditory Processing Disorders |website=American Speech-Language-Hearing Association|title=(Central) Auditory Processing Disorders—The Role of the Audiologist [Position Statement] |date=2005 |doi=10.1044/policy.PS2005-00114}}

According to the respondents who participated in a study by Neijenhuis, de Wit, and Luinge (2017),{{cite journal |last1=Neijenhuis |first1=Karin |last2=de Wit |first2=Ellen |last3=Luinge |first3=Margreet |s2cid=30517252 |title=Perspectives of Dutch health professionals regarding auditory processing disorders; a focus group study |journal=International Journal of Audiology |date=13 July 2017 |volume=56 |issue=12 |pages=942–950 |doi=10.1080/14992027.2017.1347290 |pmid=28701055|url=https://www.rug.nl/research/portal/en/publications/perspectives-of-dutch-health-professionals-regarding-auditory-processing-disorders-a-focus-group-study(6ef5d00f-ee2e-4b7d-bc50-9ccef6d84491).html }} symptoms of APD which are characteristic in children with listening difficulties, and are typically problematic with adolescents and adults, include:

• Difficulty hearing in noisy environments
• Auditory attention problems
• Understanding speech more easily in one-on-one situations
• Difficulties in noise localization
• Difficulties in remembering oral information

According to the [https://www.audiology.org.nz/assets/Uploads/APD/NZ-APD-GUIDELINES-2019.pdf New Zealand Guidelines on Auditory Processing Disorders (2017)],Keith, W.J., Purdy, S.C., Baily, M., Kay, Flora. Draft of New Zealand APD Guidelines on Auditory Processing Disorder (2018) Published by the Auditory Processing Disorders Reference Group, New Zealand Audiological Society. the following checklist of key symptoms of APD or comorbidities can be used to identify individuals who should be referred for audiological and APD assessment:

• Difficulty following spoken directions unless they are brief and simple
• Difficulty attending to and remembering spoken information
• Slowness in processing spoken information
• Difficulty understanding in the presence of other sounds
• Overwhelmed by complex or "busy" auditory environments e.g. classrooms, shopping malls
• Poor listening skills
• Insensitivity to tone of voice or other nuances of speech
• Acquired brain injury
• History of frequent or persistent middle ear disease (otitis media, "glue ear").
• Difficulty with language, reading, or spelling
• Suspicion or diagnosis of dyslexia
• Suspicion or diagnosis of language disorder or delay

Finally, the New Zealand guidelines state that behavioral checklists and questionnaires should only be used to provide guidance for referrals, for information gathering (for example, prior to assessment or as outcome measures for interventions), and as measures to describe the functional impact of auditory processing disorder. They are not designed for the purpose of diagnosing auditory processing disorders. The New Zealand guidelines indicate that a number of questionnaires have been developed to identify children who might benefit from evaluation of their problems in listening. Examples of available questionnaires include the Fisher's Auditory Problems Checklist,Fisher, L. I. (1976). Fisher's Auditory Problems Checklist. Tampa, FL. The Educational Audiology Association the Children's Auditory Performance Scale,Smoski, W.J., Brung, M.A.. and Tannahill, J.C., (1998) Children's Auditory Performance Scale, Tampa, FL: The Educational Audiology Association the Screening Instrument for Targeting Educational Risk,Anderson, K. (1989). SIFTER: Screening instrument for targeting educational risk in children identified by hearing screening or who have known hearing loss. Tampa, FL The Educational Audiology Association and the Auditory Processing Domains Questionnaire{{cite journal |last1=O'Hara |first1=Brian |last2=Mealings |first2=Kiri |s2cid=51886769 |title=Developing the auditory processing domains questionnaire (APDQ): a differential screening tool for auditory processing disorder |journal=International Journal of Audiology |volume=57 |issue=10 |date=31 July 2018 |pages=764–775 |doi=10.1080/14992027.2018.1487087 |pmid=30063869|url=https://dspace.nal.gov.au/xmlui/handle/123456789/931}} among others. All of the previous questionnaires were designed for children and none are useful for adolescents and adults.{{citation needed|date=December 2020}}

The University of Cincinnati Auditory Processing Inventory ([https://www.tandfonline.com/doi/suppl/10.1080/14992027.2019.1585973?scroll=top UCAPI])Keith, R.W., Tektas, M., and Ramsay, K. (2018) Development of the University of Cincinnati Auditory Processing Inventory for Adolescents and Adults (UCAPI), American Academy of Audiology Annual Conference. April 18–21, 2018, Nashville, TN. Research Podium Presentation.

Published in the International Journal of Audiology (IJA), 58:6. 373–378, 2019 under the same title.

DOI:10.1080/14992027.1585973{{Cite journal|last1=Keith|first1=Robert W.|last2=Tektas|first2=Melisa|last3=Ramsay|first3=Kendall|last4=Delaney|first4=Sarah|s2cid=92999722|date=2019|title=Development and standardization of the University of Cincinnati Auditory Processing Inventory (UCAPI)†|journal=International Journal of Audiology|volume=58|issue=6|pages=373–378|doi=10.1080/14992027.2019.1585973|issn=1708-8186|pmid=30939055}} was designed for use with adolescents and adults seeking testing for evaluation of problems with listening and/or to be used following diagnosis of an auditory processing disorder to determine the subject's status. Following a model described by Zoppo et al. (2015{{Cite journal|last1=Del Zoppo|first1=C.|last2=Sanchez, L.|last3=Lind, C.|s2cid=13567744|date=2015|title=A long-term follow-up of children and adolescents referred for assessment of auditory processing disorder.|journal=International Journal of Audiology|volume=54|issue=6|pages=368–375|doi=10.3109/14992027.2014.972523|pmid=25544358|url=https://figshare.com/articles/journal_contribution/1623139}}), a 34-item questionnaire was developed that investigates auditory processing abilities in each of the six common areas of complaint in APD (listening and concentration, understanding speech, following spoken instructions, attention, and other.) The final questionnaire was standardized on normally-achieving young adults ranging from 18 to 27 years of age. Validation data was acquired from subjects with language-learning or auditory processing disorders who were either self-reported or confirmed by diagnostic testing. A UCAPI total score is calculated by combining the totals from the six listening conditions and provides an overall value to categorize listening abilities. Additionally, analysis of the scores from the six listening conditions provides an auditory profile for the subject. Each listening condition can then be utilized by the professional in making recommendation for diagnosing problem of learning through listening and treatment decisions. The UCAPI provides information on listening problems in various populations that can aid examiners in making recommendations for assessment and management.{{citation needed|date=December 2021}}

APD has been defined anatomically in terms of the integrity of the auditory areas of the nervous system.{{cite book | last1 = Rintelmann | first1 = W.F. | title = Assessment of central auditory dysfunction: foundations and clinical correlates | chapter = Monaural speech tests in the detection of central auditory disorders. |editor = Marilyn L Pinheiro |editor2=Frank E Musiek | publisher = Williams & Wilkins | year = 1985 | location = Baltimore | pages = 173–200 | isbn = 978-0-683-06887-0 | oclc= 11497885 }} However, children with symptoms of APD typically have no evidence of neurological disease, so the diagnosis is made based on how the child performs behavioral auditory tests. Auditory processing is "what we do with what we hear",{{cite book | last1 = Katz | first1 = Jack | title = Central auditory processing: a transdisciplinary view | chapter = Classification of auditory processing disorders |editor = Jack Katz |editor2=Nancy Austin Stecker |editor3=Donald Henderson | publisher = Mosby Year Book | year = 1992 | location = St. Louis | pages = 81–92 | isbn = 978-1-55664-372-9| oclc= 25877287 }} and in APD there is a mismatch between peripheral hearing ability (which is typically normal) and ability to interpret or discriminate sounds. Thus in those with no signs of neurological impairment, APD is diagnosed on the basis of auditory tests. There is, however, no consensus as to which tests should be used for diagnosis, as evidenced by the succession of task force reports that have appeared in recent years.{{Update inline|date=February 2024}}

The first of these occurred in 1996.{{cite journal |last1=Task Force on Central Auditory Processing Consensus Development |first1=American Speech-Language-Hearing Association |title=Central Auditory Processing: Current Status of Research and Implications for Clinical Practice |journal=American Journal of Audiology |date=1996 |volume=5 |issue=2 |pages=41–52 |doi=10.1044/1059-0889.0502.41 |url=https://pubs.asha.org/doi/10.1044/1059-0889.0502.41 |access-date=23 October 2020}} This was followed by a conference organized by the American Academy of Audiology.{{cite journal |vauthors=Jerger J, Musiek F |title=Report of the Consensus Conference on the Diagnosis of Auditory Processing Disorders in School-Aged Children |journal=J Am Acad Audiol |volume=11 |issue=9 |pages=467–74 |date=October 2000 |doi=10.1055/s-0042-1748136 |pmid=11057730 |s2cid=18887683 }}

Experts attempting to define diagnostic criteria have to grapple with the problem that a child may do poorly on an auditory test for reasons other than poor auditory perception: for instance, failure could be due to inattention, difficulty in coping with task demands, or limited language ability. In an attempt to rule out at least some of these factors, the American Academy of Audiology conference explicitly advocated that for APD to be diagnosed, the child must have a modality-specific problem, i.e. affecting auditory but not visual processing. However, a committee of the American Speech-Language-Hearing Association subsequently rejected modality-specificity as a defining characteristic of auditory processing disorders.

in 2005 the American Speech–Language–Hearing Association published "Central Auditory Processing Disorders" as an update to the 1996 publication, "Central Auditory Processing: Current Status of Research and Implications for Clinical Practice".{{cite web |title=(Central) Auditory Processing Disorders [technical report] |url=https://www.asha.org/policy/TR2005-00043/ |website=American Speech-Language-Hearing Association |publisher=ASHA |access-date=23 October 2020 |location=Rockville (MD) |date=2005}} The American Academy of Audiology has released more current practice guidelines related to the disorder. ASHA formally defines APD as "a difficulty in the efficiency and effectiveness by which the central nervous system (CNS) utilizes auditory information."{{cite journal|last1=Paul|first1=Rhea|s2cid=33085064|title=Auditory Processing Disorder|journal=Journal of Autism and Developmental Disorders|date=25 August 2007|volume=38|issue=1|pages=208–209|doi=10.1007/s10803-007-0437-6|pmid=17721695}}

In 2018, the British Society of Audiology published a "position statement and practice guidance" on auditory processing disorder and updated its definition of APD. According to the Society, APD refers to the inability to process speech and on-speech sounds.{{cite book |last1=British Society of Audiology |title=Auditory Processing Disorder (APD) |date=2018 |publisher=British Society of Audiology |location=London, England |url=https://www.thebsa.org.uk/wp-content/uploads/2018/02/Position-Statement-and-Practice-Guidance-APD-2018.pdf |access-date=23 October 2020}}

Auditory processing disorder can be developmental or acquired. It may result from ear infections, head injuries, or neurodevelopmental delays that affect processing of auditory information. This can include problems with: "...sound localization and lateralization (see also binaural fusion); 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".

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 speech sounds. It does not solely result from a deficit in general attention, language or other cognitive processes."{{Cite web|url=https://www.thebsa.org.uk/|title=British Society of Audiology – BSA|website=British Society of Audiology}}

1. The SCAN-C{{cite web |last1=Keith|first1=Robert W.|date=2000|title=SCAN-C Test for Auditory Processing Disorders in Children |website=Pearson US |url=https://pearsonclinical.in/solutions/scan-c-test-for-auditory-processing-disorders-in-children-revised/}} for children and SCAN-A{{Cite web |last=Keith|first=Robert|date=2009|title=SCAN-3:A Tests for Auditory Processing Disorders in Adolescents and Adults.|url=https://www.pearsonassessments.com/en-us/Store/Professional-Assessments/Speech-%26-Language/SCAN-3%3AA-Tests-for-Auditory-Processing-Disorders-in-Adolescents-and-Adults/p/100000237|website=Pearson US}} for adolescents and adults are the most common tools for screening and diagnosing APD in the USA. Both tests are standardized on a large number of subjects and include validation data on subjects with auditory processing disorders. The SCAN test batteries include screening tests: norm-based criterion-referenced scores; diagnostic tests: scaled scores, percentile ranks and ear advantage scores for all tests except the Gap Detection test. The four tests include four subsets on which the subject scores are derived include: discrimination of monaurally presented single words against background noise (speech in noise), acoustically degraded single words (filtered words), dichotically presented single words and sentences.
2. Random Gap Detection Test (RGDT) is also a standardized test. It assesses an individual's gap detection threshold of tones and white noise. The exam includes stimuli at four different frequencies (500, 1000, 2000, and 4000 Hz) and white noise clicks of 50 ms duration. This test provides an index of auditory temporal resolution. In children, an overall gap detection threshold greater than 20 ms means they have failed and may have an auditory processing disorder based on abnormal perception of sound in the time domain.{{Cite journal|last1=Muluk|first1=Nuray Bayar|last2=Yalçınkaya|first2=Fulya|last3=Keith|first3=Robert W.|date=February 2011|title=Random gap detection test and random gap detection test-expanded: Results in children with previous language delay in early childhood|journal=Auris Nasus Larynx|volume=38|issue=1|pages=6–13|doi=10.1016/j.anl.2010.05.007|pmid=20599334|issn=0385-8146}}{{cite journal|last1=Keith|first1=Robert W.|title=Random gap detection test|date=2011}}
3. Gaps in Noise Test (GIN) also measures temporal resolution by testing the patient's gap detection threshold in white noise.{{cite journal|last1=Musiek|first1=Frank E.|last2=Shinn|first2=Jennifer B.|last3=Jirsa|first3=Robert|last4=Bamiou|first4=Doris-Eva|last5=Baran|first5=Jane A.|last6=Zaida|first6=Elena|s2cid=25534002|title=GIN (Gaps-In-Noise) Test Performance in Subjects with Confirmed Central Auditory Nervous System Involvement|journal=Ear and Hearing|date=December 2005|volume=26|issue=6|pages=608–618|doi=10.1097/01.aud.0000188069.80699.41|pmid=16377996}}
4. Pitch Patterns Sequence Test (PPT) and Duration Patterns Sequence Test (DPT) measure auditory pattern identification. The PPS has s series of three tones presented at either of two pitches (high or low). Meanwhile, the DPS has a series of three tones that vary in duration rather than pitch (long or short). Patients are then asked to describe the pattern of pitches presented.{{cite journal|last1=Musiek|first1=Frank|title=Frequency (Pitch) and Duration Pattern Tests|journal=Journal of the American Academy of Audiology|volume=5|issue=4|date=1994|pages=265–268|pmid=7949300}}
5. Masking Level Difference (MLD) at 500 Hz measures overlapping temporal processing, binaural processing, and low-redundancy by measuring the difference in threshold of an auditory stimulus when a masking noise is presented in and out of phase.{{Cite journal|last1=Brown|first1=Mallory|last2=Musiek|first2=Frank|date=January 2013|title=Pathways: The Fundamentals of Masking Level Differences for Assessing Auditory Function|journal=The Hearing Journal|volume=66|issue=1|page=16|doi=10.1097/01.HJ.0000425772.41884.1d|issn=0745-7472|doi-access=free}}
6. The Staggered Spondaic Word Test (SSW) is one of the oldest tests for APD developed by Jack Katz. Although it has fallen into some disuse by audiologists as it is complicated to score, it is one of the quickest and most sensitive tests to determine APD.

The issue of modality-specificity has led to considerable debate among experts in this field. Cacace and McFarland have argued that APD should be defined as a modality-specific perceptual dysfunction that is not due to peripheral hearing loss.{{cite journal | title = Opening Pandora's Box: The Reliability of CAPD Tests | journal = American Journal of Audiology | date = July 1995 | first = Anthony T. | last = Cacace | author2 = Dennis J. McFarland | volume = 4 | pages = 61–62 | url = http://aja.asha.org/cgi/content/citation/4/2/61 | access-date = 2010-08-31 | issue = 2 | archive-url = https://web.archive.org/web/20110127172849/http://aja.asha.org/cgi/content/citation/4/2/61 | archive-date = 2011-01-27 | doi = 10.1044/1059-0889.0402.61 }}{{cite journal | title = The Importance of Modality Specificity in Diagnosing Central Auditory Processing Disorder | journal = American Journal of Audiology | date = December 2005 | first = Anthony T. | last = Cacace | pmid = 16489868 | author2 = Dennis J. McFarland | volume = 14 | issue = 2 | pages = 112–123| doi = 10.1044/1059-0889(2005/012) }} They criticize more inclusive conceptualizations of APD as lacking diagnostic specificity.{{cite journal |last1=Cacace |first1=A.T. |last2=McFarland |first2=D.J. |title=Central auditory processing disorder in school-aged children: a critical review |journal=Journal of Speech, Language, and Hearing Research |date=1998 |volume=41 |issue=2 |pages=355–73 |doi=10.1044/jslhr.4102.355 |pmid=9570588}} A requirement for modality-specificity could potentially avoid including children whose poor auditory performance is due to general factors such as poor attention or memory. Others, however, have argued that a modality-specific approach is too narrow, and that it would miss children who had genuine perceptual problems affecting both visual and auditory processing. It is also impractical, as audiologists do not have access to standardized tests that are visual analogs of auditory tests.{{cite journal |last1=Bellis |first1=Teri James |last2=Ross |first2=Jody |title=Performance of normal adults and children on central auditory diagnostic tests and their corresponding visual analogs |journal=Journal of the American Academy of Audiology |date=2011 |volume=22 |issue=8 |pages=491–500 |doi=10.3766/jaaa.22.8.2 |pmid=22031674}} The debate over this issue remains unresolved between modality-specific researchers such as Cacace, and associations such as the American Speech-Language-Hearing Association (among others). It is clear, however, that a modality-specific approach will diagnose fewer children with APD than a modality-general one, and that the latter approach runs a risk of including children who fail auditory tests for reasons other than poor auditory processing. Although modality-specific testing has been advocated for well over a decade, the visual analog of APD testing has met with sustained resistance from the fields of optometry and ophthalmology.{{citation needed|date=April 2017}}{{editorializing|date=November 2019}}

Another controversy concerns the fact that most traditional tests of APD use verbal materials.{{cite journal|last=Moore|first=David R.|s2cid=145753219|year=2006|title=Auditory processing disorder (APD): Definition, diagnosis, neural basis, and intervention|journal=Audiological Medicine|volume=4|issue=1|pages=4–11|doi=10.1080/16513860600568573}} The British Society of Audiology has embraced Moore's (2006) recommendation that tests for APD should assess processing of non-speech sounds. The concern is that if verbal materials are used to test for APD, then children may fail because of limited language ability. An analogy may be drawn with trying to listen to sounds in a foreign language. It is much harder to distinguish between sounds or to remember a sequence of words in a language you do not know well: the problem is not an auditory one, but rather due to lack of expertise in the language.

In recent years there have been additional criticisms of some popular tests for diagnosis of APD. Tests that use tape-recorded American English have been shown to over-identify APD in speakers of other forms of English.{{cite journal|title=The SCAN-C in testing for auditory processing disorder in a sample of British children.|first1=P|last1=Dawes |first2=D.V. M.|last2=Bishop|s2cid=20449768|year=2007|journal=International Journal of Audiology|volume=46|issue=12|pages=780–786|doi=10.1080/14992020701545906|pmid=18049967|url=https://www.research.manchester.ac.uk/portal/en/publications/the-scanc-in-testing-for-auditory-processing-disorder-in-a-sample-of-british-children(a69403d7-9e40-4c82-90f7-674f7dbbf65c).html}} Performance on a battery of non-verbal auditory tests devised by the Medical Research Council's Institute of Hearing Research was found to be heavily influenced by non-sensory task demands, and indices of APD had low reliability when this was controlled for.{{cite journal|title=Nature of auditory processing disorder in children.|first1=D.R.|last1=Moore|first2=M.A.|last2=Ferguson|first3=A.M.|last3=Edmondson-Jones|first4=S|last4=Ratib|first5=A|last5=Riley|s2cid=34412421|year=2010|journal=Pediatrics|volume=126|issue=2|pages=e382–390|doi=10.1542/peds.2009-2826|pmid=20660546}}{{cite journal|title= Development of auditory processing in 6-11 year old children.|first1=D.R.|last1=Moore|first2=J.A.|last2=Cowan|first3=A|last3=Riley|first4=A.M.|last4=Edmondson-Jones|first5= M.A.|last5=Ferguson|s2cid=36072231|year=2011|journal=Ear and Hearing|volume=32|issue=3|pages=269–285|doi=10.1097/AUD.0b013e318201c468|pmid=21233712}} This research undermines the validity of APD as a distinct entity in its own right and suggests that the use of the term "disorder" itself is unwarranted. In a recent review of such diagnostic issues, it was recommended that children with suspected auditory processing impairments receive a holistic psychometric assessment including general intellectual ability, auditory memory, and attention, phonological processing, language, and literacy.{{cite book |title= Controversies in central auditory processing disorder |veditors=Cacace AT, McFarland DJ |chapter= Putting the Auditory Processing Back into Auditory Processing Disorder in Children |vauthors=Cowan J, Rosen S, Moore DR |pages=187–197 |year=2009 |location= San Diego, Calif. |publisher=Plural Publishing |isbn=978-159-756260-7}} The authors state that "a clearer understanding of the relative contributions of perceptual and non-sensory, unimodal and supramodal factors to performance on psychoacoustic tests may well be the key to unraveling the clinical presentation of these individuals."

Depending on how it is defined, APD may share common symptoms with ADD/ADHD, specific language impairment, and autism spectrum disorders. A review showed substantial evidence for atypical processing of auditory information in children with autism.{{cite journal |author=O'Connor K |s2cid=13991425 |title=Auditory processing in autism spectrum disorder: A review |journal=Neurosci Biobehav Rev |volume= 36|issue= 2|pages= 836–54|date=December 2011 |pmid=22155284 |doi=10.1016/j.neubiorev.2011.11.008 }} Dawes and Bishop noted how specialists in audiology and speech-language pathology often adopted different approaches to child assessment, and they concluded their review as follows: "We regard it as crucial that these different professional groups work together in carrying out assessment, treatment and management of children and undertaking cross-disciplinary research."{{cite journal |vauthors=Dawes P, Bishop D |title=Auditory processing disorder in relation to developmental disorders of language, communication and attention: a review and critique |journal=Int J Lang Commun Disord |volume=44 |issue=4 |pages=440–65 |year=2009 |pmid=19925352 |doi=10.1080/13682820902929073 |url=https://www.research.manchester.ac.uk/portal/en/publications/auditory-processing-disorder-in-relation-to-developmental-disorders-of-language-communication-and-attention-a-review-and-critique-research-report(3ef563b2-8640-4889-be16-8dee9207aa43).html }} In practice, this seems rare.{{according to whom|date=November 2019}}

To ensure that APD is correctly diagnosed, the examiners must differentiate APD from other disorders with similar symptoms. Factors that should be taken into account during the diagnosis are: attention, auditory neuropathy, fatigue, hearing and sensitivity, intellectual and developmental age, medications, motivation, motor skills, native language and language experience, response strategies and decision-making style, and visual acuity.{{cite journal|last1=Jerger|first1=James|last2=Musick|first2=Frank|title=Report of the Consensus Conference on the Diagnosis of Auditory Processing Disorders in School-Aged Children|journal=Journal of the American Academy of Audiology|date=2000|volume=11|issue=9|pages=467–474|doi=10.1055/s-0042-1748136 |pmid=11057730|s2cid=18887683 }}

It should also be noted that children under the age of seven cannot be evaluated correctly because their language and auditory processes are still developing. In addition, the presence of APD cannot be evaluated when a child's primary language is not English.{{cite journal|last1=Brandstaetter|first1=Patt|last2=Hunter|first2=Lisa|last3=Kalweit|first3=Linda|last4=Kloos|first4=Eric|last5=Landrud|first5=Sherry|last6=Larson|first6=Nancy|last7=Packer|first7=Amy|last8=Wall|first8=Deb|title=Introduction to Auditory Processing Disorders|journal=Minnesota Department of Education Total Special Education System|date=2003}}{{Ambiguous|date=November 2019}}

The American Speech-Language-Hearing Association{{cite web |title=Central Auditory Processing Disorder: Signs and Symptoms |url=https://www.asha.org/PRPSpecificTopic.aspx?folderid=8589943561§ion=Signs_and_Symptoms |website=American Speech-Language-Hearing Association |access-date=23 October 2020}} state that children with (central) auditory processing disorder often:

• have trouble paying attention to and remembering information presented orally, and may cope better with visually acquired information
• have problems carrying out multi-step directions given orally; need to hear only one direction at a time
• have poor listening skills
• need more time to process information
• have difficulty learning a new language
• have difficulty understanding jokes, sarcasm, and learning songs or nursery rhymes
• have language difficulties (e.g., they confuse syllable sequences and have problems developing vocabulary and understanding language)
• have difficulty with reading, comprehension, spelling, and vocabulary

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. In addition, it is common for APD to cause speech errors involving the distortion and substitution of consonant sounds.{{cite conference |last1=DeVore |first1=Brooke |last2=Nagao |first2=Kyoko |last3=Pereira |first3=Olivia |last4=Nemith |first4=Julianne |last5=Sklar |first5=Rachele |last6=Deeves |first6=Emily |last7=Kish |first7=Emily |last8=Welsh |first8=Kelsey |last9=Morlet |first9=Thierry |title=Speech errors among children with auditory processing disorder |conference=Proceedings of Meetings on Acoustics |date=2016 |volume=29 |issue=1 |page=6 |doi=10.1121/2.0000440 |doi-access=free}} Those with 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, since spoken words may sound distorted either into irrelevant words or words that do not exist, depending on the severity of the auditory processing disorder.{{cite journal |vauthors=Anderson S, Kraus N |title=Sensory-cognitive interaction in the neural encoding of speech in noise: a review |journal=J Am Acad Audiol |volume=21 |issue=9 |pages=575–85 |date=October 2010 |pmid=21241645 |pmc=3075209 |doi=10.3766/jaaa.21.9.3 }} 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. 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.{{citation needed|date=December 2020}}

As noted above, the status of APD as a distinct disorder has been queried, especially by speech-language pathologists{{cite journal|first=A.G.|last=Kamhi|s2cid=18198216|year=2011|title= What speech-language pathologists need to know about Auditory Processing Disorder.|journal=Language, Speech, and Hearing Services in Schools|volume= 42|issue=3|pages=265–272|doi=10.1044/0161-1461(2010/10-0004)|pmid=20844272}} and psychologists,{{cite journal|last=Lovett|first=B.J.|year=2011|title=Auditory processing disorder: School psychologist beware?|journal=Psychology in the Schools|volume=48|issue=8|pages=855–867|doi=10.1002/pits.20595}} who note the overlap between clinical profiles of children diagnosed with APD and those with other forms of specific learning disability. Many audiologists, however, would dispute that APD is just an alternative label for dyslexia, SLI, or ADHD, noting that although it often co-occurs with these conditions, it can be found in isolation.{{cite journal|journal=Hearing Journal|year=2001|volume = 54|issue =7|pages=10–25|doi=10.1097/01.HJ.0000294109.14504.d8|title= Auditory processing disorder: An overview for the clinician|last=Chermak|first=Gail D|s2cid=147238455 |doi-access=free}}

Based on sensitized measures of auditory dysfunction and on psychological assessment, patients can be subdivided into seven subcategories:{{cite journal |vauthors=Zhao F, Stephens D |s2cid=13246195|title=Subcategories of patients with Auditory Processing Disorder|journal=Br J Audiol |volume=34 |issue=4 |pages=241–56 |date=August 2000 |pmid=10997453|doi=10.3109/03005364000000134}}

1. middle ear dysfunction
2. mild cochlear pathology
3. central/medial olivocochlear efferent system (MOCS) auditory dysfunction
4. purely psychological problems
5. multiple auditory pathologies
6. combined auditory dysfunction and psychological problems
7. unknown

Different subgroups may represent different pathogenic and etiological factors. Thus, subcategorization provides further understanding of the basis of auditory processing disorder, and hence may guide the rehabilitative management of these patients. This was suggested by Professor Dafydd Stephens and Fei Zhao at the Welsh Hearing Institute, Cardiff University.{{Cite journal|url=https://informahealthcare.com/doi/abs/10.3109/03005364000000134|title=Subcategories of Patients with King-Kopetzky Syndrome|journal=British Journal of Audiology|date=2000 |via=informahealthcare.com|doi=10.3109/03005364000000134 |last1=Zhao |first1=F. |last2=Stephens |first2=D. |volume=34 |issue=4 |pages=241–256 |pmid=10997453 |s2cid=13246195 }}

{{See also|Alternative therapies for developmental and learning disabilities}}

Treatment of APD typically focuses on three primary areas: changing learning environment, developing higher-order skills to compensate for the disorder, and remediation of the auditory deficit itself.{{cite web|last1=Bellis|first1=Teri James|title=Auditory Processing Disorders (APD) in Children|url=https://www.asha.org/public/hearing/Understanding-Auditory-Processing-Disorders-in-Children/|website=www.asha.org|publisher=ASHA}} However, there is a lack of well-conducted evaluations of intervention using randomized controlled trial methodology. Most evidence for effectiveness adopts weaker standards of evidence, such as showing that performance improves after training. This does not control for possible influences of practice, maturation, or placebo effects. Recent research has shown that practice with basic auditory processing tasks (i.e. auditory training) may improve performance on auditory processing measures{{cite journal |vauthors=Chermak GD, Silva ME, Nye J, Hasbrouck J, Musiek FE |s2cid=36265513 |title=An update on professional education and clinical practices in central auditory processing |journal=J Am Acad Audiol |volume=18 |issue=5 |pages=428–52; quiz 455 |date=May 2007 |pmid=17715652 |doi= 10.3766/jaaa.18.5.7}}{{cite journal |author=Moore DR |title=Auditory processing disorders: acquisition and treatment |journal=J Commun Disord |volume=40 |issue=4 |pages=295–304 |year=2007 |pmid=17467002 |doi=10.1016/j.jcomdis.2007.03.005 }} and phonemic awareness measures.{{cite journal |vauthors=Moore DR, Rosenberg JF, Coleman JS |s2cid=3895590 |title=Discrimination training of phonemic contrasts enhances phonological processing in mainstream school children |journal=Brain Lang |volume=94 |issue=1 |pages=72–85 |date=July 2005 |pmid=15896385 |doi=10.1016/j.bandl.2004.11.009 }} Changes after auditory training have also been recorded at the physiological level.{{cite journal |vauthors=Russo NM, Nicol TG, Zecker SG, Hayes EA, Kraus N |s2cid=332303 |title=Auditory training improves neural timing in the human brainstem |journal=Behav. Brain Res. |volume=156 |issue=1 |pages=95–103 |date=January 2005 |pmid=15474654 |doi=10.1016/j.bbr.2004.05.012 }}{{cite journal |vauthors=Alonso R, Schochat E |title=The efficacy of formal auditory training in children with (central) auditory processing disorder: behavioral and electrophysiological evaluation |journal=Braz J Otorhinolaryngol |volume=75 |issue=5 |pages=726–32 |year=2009 |pmid=19893943 |doi=10.1590/S1808-86942009000500019 |pmc=9442236 |doi-access=free }} Many of these tasks are incorporated into computer-based auditory training programs such as Earobics and Fast ForWord, an adaptive software available at home and in clinics worldwide, but overall, evidence for effectiveness of these computerized interventions in improving language and literacy is not impressive.{{cite journal|last1=Loo|first1=J.H.Y.|last2=Bamiou|first2=D.-E.|last3=Campbell|first3=N.|last4=Luxon|first4= L.M.|year=2010|title= Computer-based auditory training (CBAT): benefits for children with language- and reading-related learning difficulties|journal=Developmental Medicine and Child Neurology|volume=52|issue=8|pages=708–717|doi=10.1111/j.1469-8749.2010.03654.x|pmid=20370814|doi-access=free}} One small-scale uncontrolled study reported successful outcomes for children with APD using auditory training software.{{cite journal |vauthors=Cameron S, Dillon H |title=Development and Evaluation of the LiSN & Learn Auditory Training Software for Deficit-Specific Remediation of Binaural Processing Deficits in Children: Preliminary Findings |journal=Journal of the American Academy of Audiology |volume=22 |issue=10 |pages=678–96 |date=November 2011 |pmid=22212767 |doi=10.3766/jaaa.22.10.6 }}

Treating additional issues related to APD can result in success. For example, treatment for phonological disorders (difficulty in speech) can result in success in terms of both the phonological disorder as well as APD. In one study, speech therapy improved auditory evoked potentials (a measure of brain activity in the auditory portions of the brain).{{cite journal |vauthors=Leite RA, Wertzner HF, Matas CG |title=Long latency auditory evoked potentials in children with phonological disorder |journal=Pró-fono: Revista de Atualização Científica |volume=22 |issue=4 |pages=561–6 |year=2010 |pmid=21271117 |doi= 10.1590/s0104-56872010000400034|doi-access=free }}

While there is evidence that language training is effective for improving APD, there is no current research supporting the following APD treatments:

• Auditory Integration Training typically involves a child attending two 30-minute sessions per day for ten days.{{cite book|title= Controversial Therapies for Developmental Disabilities|veditors=Jacobson JW, Foxx RM, Mulick JA |chapter= Auditory integration training: a critical review|vauthors=Mudford OC, Cullen C |pages=351–62|year=2004|publisher=Routledge|isbn=978-0-8058-4192-3}}
• 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
• Neuro-Sensory Educational Therapy
• Neurofeedback

The use of an individual FM transmitter/receiver system by teachers and students has nevertheless been shown to produce significant improvements with children over time.{{Cite journal|title=A Randomized Control Trial of Interventions In School-Aged Children with Auditory Processing Disorders|url=https://www.researchgate.net/publication/224707121 |author=Sharma, Mridula |author2=Purdy, Suzanne |author3=Kelly, Andrea|s2cid=25414619|date=2012|journal=International Journal of Audiology|volume=51|issue=7|pages=506–18|doi=10.3109/14992027.2012.670272|pmid=22512470}}

Samuel J. Kopetzky first described the condition in 1948. P. F. King first discussed the etiological factors behind it in 1954.{{cite journal|url = http://www.noiseandhealth.org/article.asp?issn=1463-1741;year=2003;volume=5;issue=20;spage=55;epage=62;aulast=Stephens|title = Is there an association between noise exposure and King Kopetzky Syndrome?|journal = Noise and Health|date = July 2003|volume = 5|issue = 20|access-date = 31 July 2010|last1 = Stephens|first1 = D.|last2 = Zhao|first2 = F.|last3 = Kennedy|first3 = V.|pages = 55–62|pmid = 14558893}} Helmer Rudolph Myklebust's 1954 study, "Auditory Disorders in Children".Myklebust, H. (1954). Auditory disorders in children. New York: Grune & Stratton. OCLC 553322 suggested auditory processing disorder was separate from language learning difficulties. His work sparked interest in auditory deficits after acquired brain lesions affecting the temporal lobes{{cite journal |vauthors=Bocca E, Calearo C, Cassinari V |title=A new method for testing hearing in temporal lobe tumours; preliminary report |journal=Acta Oto-Laryngologica |volume=44 |issue=3 |pages=219–21 |year=1954 |pmid=13197002 |doi= 10.3109/00016485409128700}}{{cite journal |vauthors=Bocca E, Calearo C, Cassinari V, Migliavacca F |title=Testing "cortical" hearing in temporal lobe tumours |journal=Acta Oto-Laryngologica |volume=45 |issue=4 |pages=289–304 |year=1955 |pmid=13275293 |doi= 10.3109/00016485509124282}} and led to additional work looking at the physiological basis of auditory processing,{{cite journal|last1=Kimura|first1=Doreen|title=Cerebral dominance and the perception of verbal stimuli.|journal=Canadian Journal of Psychology |

volume=15|issue=3|year=1961|pages=166–171|issn=0008-4255|doi=10.1037/h0083219}} but it was not until the late seventies and early eighties that research began on APD in depth.

In 1977, the first conference on the topic of APD was organized by Robert W. Keith, Ph.D. at the University of Cincinnati. The proceedings of that conference was published by Grune and Stratton under the title "Central Auditory Dysfunction" (Keith RW Ed.) That conference started a new series of studies focusing on APD in children.Katz, J., & Illmer, R. (1972). Auditory perception in children with learning disabilities. In J. Katz (Ed.), Handbook of clinical audiology (pp. 540–563). Baltimore: Williams & Wilkins. OCoLC 607728817{{cite book |author=Keith, Robert W. |title=Central auditory dysfunction: University of Cincinnati Medical Center Division of Audiology and Speech Pathology symposium |publisher=Grune & Stratton |location=New York |year=1977 |isbn=978-0-8089-1061-9 |oclc=3203948 |url=https://archive.org/details/centralauditoryd00keit }}{{cite journal |vauthors=Sweetow RW, Reddell RC |title=The use of masking level differences in the identification of children with perceptual problems |journal=J Am Audiol Soc |volume=4 |issue=2 |pages=52–6 |year=1978 |pmid=738915 }}{{cite journal |vauthors=Manning WH, Johnston KL, Beasley DS |title=The performance of children with auditory perceptual disorders on a time-compressed speech discrimination measure |journal=J Speech Hear Disord |volume=42 |issue=1 |pages=77–84 |date=February 1977 |pmid=839757 |doi= 10.1044/jshd.4201.77}}{{cite book |author=Willeford, J. A. |chapter=Assessing central auditory behavior in children A test battery approach |title=Central auditory dysfunction |editor=Keith, Robert W. |publisher=Grune & Stratton |location=New York |year=1977 |pages=[https://archive.org/details/centralauditoryd00keit/page/43 43–72] |isbn=978-0-8089-1061-9 |oclc=3203948 |chapter-url=https://archive.org/details/centralauditoryd00keit |url=https://archive.org/details/centralauditoryd00keit/page/43 }} Virtually all tests currently used to diagnose APD originate from this work. These early researchers also invented many of the auditory training approaches, including interhemispheric transfer training and interaural intensity difference training. This period gave us a rough understanding of the causes and possible treatment options for APD.

Much of the work in the late nineties and 2000s has been looking to refining testing, developing more sophisticated treatment options, and looking for genetic risk factors for APD. Scientists have worked on improving behavioral tests of auditory function, neuroimaging, electroacoustic, and electrophysiologic testing.{{cite journal |vauthors=Jerger J, Thibodeau L, Martin J |title=Behavioral and electrophysiologic evidence of auditory processing disorder: a twin study |journal=J Am Acad Audiol |volume=13 |issue=8 |pages=438–60 |date=September 2002 |pmid=12371661 |doi= 10.1055/s-0040-1716007|display-authors=etal}}{{cite journal |vauthors=Estes RI, Jerger J, Jacobson G |title=Reversal of hemispheric asymmetry on auditory tasks in children who are poor listeners |journal=J Am Acad Audiol |volume=13 |issue=2 |pages=59–71 |date=February 2002 |pmid=11895008 |doi= 10.1055/s-0040-1715949}} Working with new technology has led to a number of software programs for auditory training.{{cite journal |vauthors=Chermak GD, Musiek FE |title=Auditory training: Principles and approaches for remediation and managing auditory processing disorders |journal=Seminars in Hearing |volume=23 |issue=4 |pages=287–295 |year=2002 |issn=0734-0451 |doi=10.1055/s-2002-35878 |s2cid=260312631 }}{{cite journal |author=Musiek F |title=Habilitation and management of auditory processing disorders: overview of selected procedures |journal=J Am Acad Audiol |volume=10 |issue=6 |pages=329–42 |date=June 1999 |doi=10.1055/s-0042-1748504 |pmid=10385875 |s2cid=11936281 }} With global awareness of mental disorders and increasing understanding of neuroscience, auditory processing is more in the public and academic consciousness than in years past.{{cite journal |vauthors=Jerger J, Musiek F |title=Report of the Consensus Conference on the Diagnosis of Auditory Processing Disorders in School-Aged Children |journal=J Am Acad Audiol |volume=11 |issue=9 |pages=467–74 |date=October 2000 |doi=10.1055/s-0042-1748136 |pmid=11057730 |s2cid=18887683 |url=http://www.bsnpta.org/geeklog/public_html/filemgmt/filemgmt_data/files/Auditory_Processing_Disorders_in_Children.pdf |access-date=2012-05-24 |url-status=usurped |archive-url=https://web.archive.org/web/20130621224822/http://www.bsnpta.org/geeklog/public_html/filemgmt/filemgmt_data/files/Auditory_Processing_Disorders_in_Children.pdf |archive-date=2013-06-21 }}{{cite book |author=Keith, Robert W. |title=Central auditory and language disorders in children |publisher=College-Hill Press |location=San Diego, CA |year=1981 |isbn=978-0-933014-74-9 |oclc=9258682 }}{{cite book |author1=Katz, Jack |author2=Henderson, Donald |author3=Stecker, Nancy Austin |title=Central auditory processing: a transdisciplinary view |publisher=Mosby Year Book |location=St. Louis, MO |year=1992 |isbn=978-1-55664-372-9 |oclc= 2587728 }}{{cite book |author1=Katz, Jack |author2=Stecker, Nancy Austin |title=Central auditory processing disorders: mostly management |publisher=Allyn and Bacon |location=Boston |year=1998 |isbn=978-0-205-27361-4 |oclc=246378171 }}

• Amblyaudia
• Auditory verbal agnosia
• Cocktail party effect
• Cortical deafness
• Dafydd Stephens
• Echoic memory
• Hearing loss
• Language processing
• List of eponymous diseases
• Music-specific disorders
• Selective auditory attention
• Selective mutism
• Sensory processing disorders
• Spatial hearing loss

{{Reflist}}

• [http://journals.lww.com/thehearingjournal/Fulltext/2001/07000/Auditory_processing_disorder__An_overview_for_the.3.aspx Auditory processing disorder: An overview for the clinician]
• [https://web.archive.org/web/20110725015810/http://search.asha.org/default.aspx?q=auditory+processing+disorder American Speech-Language-Hearing Association (ASHA)]

{{Medical resources

| DiseasesDB =

| ICD10 = {{ICD10|H93.2}}

| ICD9 = {{ICD9|388.45}} {{ICD9|388.40}}

| ICDO =

| OMIM =

| MedlinePlus =

| eMedicineSubj =

| eMedicineTopic =

| MeshID = D001308

}}

{{Hearing and balance}}

{{CNS diseases of the nervous system}}

{{Authority control}}

{{DEFAULTSORT:Auditory Processing Disorder}}

Category:Neurological disorders

Category:Audiology

Category:Psychoacoustics

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Category:Learning disabilities

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Category:Phonology

Category:Speech processing

Category:Special education

Category:Communication disorders

Category:Syndromes