Central Auditory Processing Disorders (CAPD) is a symptom complex that can be vague and difficult to detect in some and represent a devastating learning disability to others. Auditory processing in its basic definition constitutes "what we do with what we hear." According to Katz et al. (1992) "it is the ability of the brain to process incoming auditory signals." The brain identifies sound by pitch, loudness, and duration--the perceptual correlates of frequency, intensity, and time. Once the brain's analysis is complete, it develops an "image" of the signal and compares it to other auditory images stored in the brain. When a matching of the two auditory "images" occur, the brain processes the match and recognizes what is being said or what importance those past sounds have at that time-honking horn, barking dog, etc.
Difficulties encountered by those with CAPD may include some of the following characteristics in whole or in part or in varied combinations: Attention related issues such as directing, sustaining, or dividing attention; difficulty staying on the topic of conversation; difficulty implementing oral instructions; problems hearing and understanding speech on the telephone or television; difficulty taking notes; general organizational skill deficits; difficulty understanding the content of a talker's message in noisy situations or in the presence if distracting auditory signals-easily distracted from content; poor listening skills; difficulty understanding speech in unfavorable acoustic environments.
Of course, many of the above difficulties can be the result of conductive or sensorineural hearing loss. Anyone suspected of having CAPD should have a comprehensive audiologic evaluation. CAPD often co-exists with other disabilities, including hearing loss, speech and language disorders or delays, learning disabilities or dyslexia, attention deficit disorders with or without hyperactivity, social and/or emotional difficulties and academic failure. Estimates of the prevalence of CAPD in children range from 2 to 5% with males having twice the incidence than females.
At Audiology & Speech Associates we approach CAPD evaluation and management from both the audiology as well as the functional receptive language aspect. As such, both audiologists and speech-language pathologists will be involved in a team approach to each individuals processing problem.
There are several behavioral and electrophysiologic tests our audiologists will use to assess central auditory function. Selection of the tests will depend on a variety of factors not the least of which will be the age of appropriateness of the material to be used and the child or adult's ability to respond to a variety of speech signals modified to assess processing abilities. Children under the age of 5 or those with significant development delays/cognitive deficits may not qualify for testing. Additionally, adults with cognitive deficits may not qualify for evaluation.
Speech-Language Pathologists will focus primarily on receptive language utility and will assess expressive parameters as well. Commonly used assessment tools for receptive language function as well as specific tools to evaluate CAPD will be used to develop the clinical picture and guide clinical management. Particular attention will be placed on assessing processing skills necessary for successful classroom participation.
Management of CAPD will depend on the specific needs of each individual. Planning and actions to be taken will be discussed with parents or patient as well as those interacting with children in school. In some situations, specific IEPs may be recommended and activities may be coordinated with school psychologists, teachers or speech-language pathologists in their respective districts. Primary Care Providers will be notified of the findings and recommendations and may be called upon to consider medical management, referral or other involvement as indicated by the respective school system. We have found that a well-coordinated, interdisciplinary approach to the problem of auditory processing disorders fosters smooth classroom integration and represents a successful intervention for everyone- especially the person with CAPD!