Newswise — One professor of otolaryngology states that "auditory processing disorder (APD) is to the ear as dyslexia is to the eye." In other words, children with APD can hear, but a problem exists in the brain process of translating sound into understandable speech. No one knows the true number of children affected by this disorder.
Children with APD are often identified through their behavior by teachers, parents, and healthcare professionals based on certain indications such as inattention, inability to follow directions, difficulty with language, reading, spelling, comprehension, and vocabulary, and difficulty carrying out multi-step directions. It is believed that difficulties with auditory processing may be associated with a range of learning disorders including Attention Deficit/Hyperactivity Disorder (ADHD), Specific Language Impairment (SLI), and Specific Reading Disability (SRD, "dyslexia" ).
Researchers, Justin Cowan, Adrian Davis, Sally Hind, and David Moore at the Medical Research Council Institute of Hearing Research, in University Park, Nottingham, United Kingdom, have addressed the absence of a reliable screening tool. In the first phase of their study, "Diagnosing Auditory Processing Disorder (APD): The Auditory Processing Inventory for Children (APIC)," the authors present APIC as a new screening tool for children suspected of having APD, while plans for the second phase (now underway) include validation of APIC and development of a standard battery of diagnostic behavior tests for APD. Their research is being presented at the Mid Winter Meeting of the Association for Research in Otolaryngology (http://www.aro.org) being held February 22-26, 2004, at the Adam's Mark Hotel, Daytona Beach, FL.
Methodology: This project explores the diagnosis of APD in children aged five to 14 using a self-report questionnaire and audiological test battery.
Phase 1: The self-reporting APIC test, designed for use by parent and child, is based on another self-report inventory, the 'Speech-, Spatial- and Qualities-of-Hearing' Questionnaire, used mainly to examine hearing handicap in the elderly. APIC consists of 37 real-life scenarios describing situations thought to be affected by APD. Items are rated on a 4-point scale by the child or parent. The test includes subscales for spatial localization, auditory discrimination, pattern recognition, temporal processing, and performance decrements with competing acoustic signals or degraded signals. Accompanying the test is a form completed by parents and teachers containing questions about the child's medical and educational history, listening abilities, and several items designed to indicate the presence or absence of attention or memory problems. To date, APIC has been given to more than 600 children and 285 parents.
Phase 2: (ongoing) Participants recruited in Phase 1 are randomly selected for audiological evaluation to assess hearing ability (including otoscopy, pure-tone audiometry, otoacoustic emissions measures, tympanometry and measurement of the acoustic reflex thresholds), tests of auditory processing (including binaural, temporal, frequency and intensity components), and tests of cognitive functioning (including attention, memory, phonological, linguistic and general cognitive abilities).
Results: The APIC questionnaire and subscales have been found to have good potential sensitivity to differences between children and normative data were reported at the meeting. It is hoped that the audiological validation of the APIC (Phase 2) will obtain reliable estimates of various aspects of auditory processing within the shortest possible time.
Conclusion: The APIC and the audiological test battery will represent a considerable advance in the objective screening and diagnosis of children with APD. With these tools it will be possible to determine what the normal range of abilities are for children on each of these tests and what typical profiles of test scores might look like, as well as identify discrete auditory processing deficits. These findings will enable clinicians to judge the appropriateness of using the label "Auditory Processing Disorder."