Questionnaires can be used for the identification of persons with possible<unk> s, as these address common problems of listening. They can help in the decision for pursuing clinical evaluation. One of the most common listening problems is speech recognition in the presence of background noise. According to the respondents who participated in a study by Neijenhuis, de Wit, and Luinge (2017), the following symptoms are characteristic in children with listening difficulties, and they are typically problematic with adolescents and adults. They include: * Difficulty hearing in noise * Auditory attention problems * Better understanding in one on one situations * Difficulties in noise localization * Difficulties in remembering oral information According to the New Zealand Guidelines on<unk> s (2017) a checklist of key symptoms of APD or comorbidities that can be used to identify individuals who should be referred for audiological and APD assessment includes, among others: * Difficulty following spoken directions unless they are brief and simple * Difficulty attending to and remembering spoken information * Slowness in<unk>  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<unk>  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<unk> . They are not designed for the purpose of diagnosing<unk> s. 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, the Children's Auditory Performance Scale, the Screening Instrument for Targeting Educational Risk, and the Auditory<unk>  Domains Questionnaire among others. All of the previous questionnaires were designed for children and none are useful for adolescents and adults. The University of Cincinnati Auditory<unk>  Inventory ( UCAPI) 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<unk>  to determine the subject's status. Following a model described by Zoppo et al. (2015) a 34-item questionnaire was developed that investigates auditory<unk>  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<unk> s 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. APD has been defined anatomically in terms of the integrity of the auditory areas of the nervous system. However, children with symptoms of APD typically have no evidence of neurological disease and the diagnosis is made on the basis of performance on behavioral auditory tests. Auditory<unk>  is "what we do with what we hear", 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. The first of these occurred in 1996. 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<unk> . However, a committee of the American Speech-Language-Hearing Association subsequently rejected modality-specificity as a defining characteristic of<unk> s. Definitions in 2005 The American Speech-Language-Hearing Association (ASHA) published "Central<unk> s" as an update to the 1996 "Central Auditory<unk> : Current Status of Research and Implications for Clinical Practice". The American Academy of Audiology has released more current practice guidelines related to the<unk> . 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<unk>  (APD) updated its definition of APD. According to the Society, APD refers to the inability to process speech and on-speech sounds.<unk>  can be developmental or acquired. It may result from ear infections, head injuries or neurodevelopmental delays that affect<unk>  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<unk>  Research Program have developed the following working definition of<unk> : "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." Types of testing # The SCAN-C for children and SCAN-A 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<unk> s. 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. # 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. It is a useful test because it 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<unk>  based on abnormal perception of sound in the time domain. # Gaps in Noise Test (GIN) also measures temporal resolution by testing the patient's gap detection threshold in white noise. # 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. # Masking Level Difference (MLD) at 500 Hz measures overlapping temporal<unk> , binaural<unk> , and low-redundancy by measuring the difference in threshold of an auditory stimulus when a masking noise is presented in and out of phase. # 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. Modality-specificity and controversies 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. They criticise more inclusive conceptualizations of APD
Auditory processing disorder
Olfactory fatigue
Vibroacoustic disease
Olfactory reference syndrome
Auditory fatigue
Cortical deafness
Speech disorder
Post-lingual deafness