This was followed by a conference organized by the American Academy of Audiology.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. Definitions
in 2005 The American Speech-Language-Hearing Association (ASHA) published "Central Auditory Processing Disorders" as an update to the 1996 "Central Auditory Processing: Current Status of Research and Implications for Clinical Practice". The American Academy of Audiology has released more current practice guidelines related to the disorder. ASHA formally defines APA as "a difficulty in the efficiency and effectiveness by which the central nervous system (CNS) utilizes auditory information. "In 2018, the British Society of Audiology published a position statement and practice guidance on auditory processing disorder (APD) updated its definition of APD. According to the Society, APD refers to the inability to process speech and on-speech sounds.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.
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. Performance on a battery of non-verbal auditory tests devised by the Medical Research Councils 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. 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. 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 unravelling 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.