Auditory Processing Disorder
The child with Auditory Processing Disorder (APD) has difficulty processing auditory information or quite simply processing what we hear, despite having normal hearing. Over the past thirty years there have been many misconceptions and false information surrounding APD. This has caused confusion over what exactly APD is and how it is diagnosed and most importantly how it is managed with relation to special education. The American Speech-Language-Hearing Association defines APD as an auditory deficit affecting how the central nervous system processes information.(A) Correlations have been made between APD, Autism, Attention Deficit Disorder, Attention Deficit Hyperactivity Disorder and Dyslexia. As a result, the existence of APD have been questioned by some. Although these disorders present similarly and co-morbidity may exist, they are distinct clinical conditions with different and unique diagnostic criteria. One should not be mistaken for the other. In this paper, I will discuss the history, diagnosis, interventions, and special education considerations as indicated by law.
Keywords: Auditory Processing Disorder, auditory information, central nervous system.
History of Auditory Processing Disorder
What is Auditory Processing Disorder? Auditory Processing Disorder, commonly referred to as Central Auditory Processing Disorder or APD/CAPD, is not a disease. Rather, APD refers to a set of problems a child may experience when faced with certain listening tasks. These children typically present with normal hearing. The problem lies in the higher auditory pathways of the central nervous system. In other words, the central nervous system has difficulties processing information that comes from listening. This is especially difficult in environments with extensive background noise. APD may manifest itself in a variety of ways. Examples include poor performance in listening tasks, comprehending speech and developing language skills (B).
To add some context, a brief history of this disorder is necessary. Early 20th Century definitions include the title “Word Deafness” or simply put, the inability to understand spoken words. This is an obvious barrier to understanding and development. More succinctly, APD is the inability of the brain to properly process and interpret auditory information. In the mid 20th Century, widely considered the dawn of research with respect to Auditory Processing Disorder, Psychologist Helmer Myklebust of Northwestern University focused his interest in auditory function and cognition. While at Northwestern, Myklebust researched learning disabilities with relation to children who had diminished communicative ability as a result of a hearing deficit. The correlation between hearing and how the brain processes what is heard became foundational to his research. Researchers like Mykelbust and James Jerger, PhD, the founder of The American Academy of Audiology, committed much of their professional careers to the study of Auditory Processing Disorder. Federal financial support of research became important to the study of APD and many other areas of the Communicative Sciences, in general. This research continued well in to the 1970’s when Jerger developed the first scientifically validated testing protocol for APD. Patients from Baylor College of Medicine were the first subjects of these testing procedures. These patients suffered with many different types of brain defects. What made their testing procedures so significant, is that they were effective in diagnosing patients with a wide variety of brain problems and were responsive to these central nervous system issues. These testing procedures are still commonly used in Audiology to this day.
Diagnosis
It is important when screening for APD to use a multidiscipline approach in order to rule out other disorders. School psychologists and Speech Language Pathologists are able to perform specific tests that will help to exclude cognitive or language disorders. Though children with APD typically have normal hearing, a screening should be performed to rule out a deficit. This approach will help to eliminate misdiagnosis as well as unnecessary referrals. Testing for APD includes a thorough case history along with a test battery that was specifically designed for children ages 3-11 years old, by Robert Keith in 1986 called The SCAN (Stern, C. 2016) VALIDITY DISSERTATION. This test battery is the most widely used screening tool because it is easy to administer and score. After several revisions the current SCAN-3 C batteries are used not only as a screening tool, but as a diagnostic tool for APD. Administered by an audiologist, the child is screened for Gap Detection, Auditory Figure Ground, Competing Words (free recall), Filtered Words, and Competing Sentences. Gap Detection measures the child’s ability to detect gaps of silence in between tones. Auditory Figure Ground assess the subject’s ability to understand speech in the presence of background noise, this is used as a screening test or diagnostic tool. Competing words is where the subject will be given two monosyllabic word pairs simultaneously to the right and left ear, the child will be instructed to repeat the words in order. This is used to assess the child’s ability to process competing speech signals. Filtered Words will evaluate the child’s ability to understand distorted speech. And finally, Competing Sentences is where the child is presented with competing sentences in each ear. The child will be asked to repeat one sentence heard in one ear and ignore the other. Both the ASHA (2005) and the American Academy of Audiology (AAA) (2010) take a similar stance on the screening and diagnosing of APD. They indicate that “the APD test battery should be based on the individual’s case history and other information provided to the audiologist, rather than a preset battery of tests for all patients.” APD affects roughly 5-7% of school-aged children, proper diagnosis is essential due to the struggles this child has academically. It is quite common that this disorder is confused with or misdiagnosed as ADHD because many of the cognitive functions like memory processing and attentiveness that ADHD affects, are needed to correct auditory processing. Just because there is a correlation between the two does not mean that ADHD is the cause of APD. Dyslexia is also another common misdiagnosis because of the fact that children who have APD also have language cognition challenges. Even though some children who suffer from Dyslexia also suffer from APD, they are separate diagnoses. Commonalities also seem to exist with Autism and as with ADHD, children who suffer from APD do not have to have a diagnosis of Autism but they can co-exist.
Clearly, the fact that there has been so much research of many different types of learning disabilities, it is not uncommon that diagnosis of a specific one can be difficult. This is what makes proper screening and early detection imperative when diagnosing and ultimately treating APD.
Interventions
Causality of APD in children could be associated with neurodevelopment deficits, head trauma, chronic ear infections, but often the cause is unknown. The treatment course is often nebulous. For some children, benefits may be realized with Speech Therapy. Others might do well when they experience priority seating in the classroom environment. The point is, there is not a “one size fits all” approach. Any type of intervention or “treatment” must be personalized to the child’s strengths and weaknesses (REFERENCE Intervention Approaches for individuals with APD) Based on my research of early studies of APD, it would not be surprising if many of these children were misdiagnosed. As a contrast, children who have been diagnosed with ADHD are often times prescribed medication as a treatment. I find it difficult to conceptualize a child that is diagnosed with APD being prescribed a medication, considering the prevalence of misdiagnosis. As cited in the University of South Dakota study, “Intervention Approaches for Individuals With CAPD”, the types of intervention approaches can be divided into three unique categories: (a) environmental modifications, (b) compensatory strategies, and central resources training, and (c) direct skills remediation. Each offer different aspects that allow a tailored approach to helping the child adapt to this disorder.
Affording the child learning structures that are more conducive to APD is achieved by modifying certain environmental aspects is the essence of the environmental modifications approach. This can be achieved through the use of hearing assistive technology, carefully planned architectural interventions intended to reduce acoustic distortion in a particular room, or even direct line of sight priority seating in the classroom, In any of these environmental modifications, it is absolutely essential that the educator is constantly assessing the effectiveness of the strategy to determine if other communicative methods need to be utilized.
Compensatory strategies, or otherwise characterized as central resources training, is primarily focused on helping ones with APD take a more active approach to listening. These strategies often times are utilized when the subject is dealing with residual disability associated with APD and the active listening approach relies on the child to take a high level of responsibility for their learning improvement. This can also be an effective tool to help enhance retention or memory skills.
Through evaluation, a more controversial type of intervention might be indicated. This has stirred controversy because of perceived inconsistencies in its’ level of effectiveness and its experimental nature. Auditory training is a type of direct remediation that utilizes either a sound booth or other targeted activities to help retrain the way that the brain processes sound. These particular activities have limited effectiveness without very frequent, intensive application. The training is is marked by achieving a level of success in an area before the difficulty of the tasks are increased.
As discussed earlier, a multidisciplinary approach should be tailored in a systematic way that targets specific cases in specific ways, as opposed to a one size fit’s all approach.
Some strategies that the educator might use can include: preferred seating, visual cues, fewer task at a time, concise directions, and word sequencing strategies. More intensive training can also include the use of FM systems to reduce background noise and computer programs to train the brain (direct remediation).
Special Education Considerations
As an educator, it is extremely important to be able to recognize when a student is having difficulty with different tasks. Children who suffer from APD sometimes slip through the cracks. It is incumbent upon us, as indicated by the IDEA Act, all children should be afforded a free, appropriate public education in the least restrictive environment. There has been contention in how APD is classified under the IDEA Act. Some states have classified APD as “speech or other impairment” while other states classify APD as “specific learning disability.” In terms of classifying children with APD, the courts have been very clear. in 2014, the U.S. 9th Circuit Court of Appeals ruled in EM v. Pajaro Valley Unified School District, that APD constitutes an “other health impairment” under IDEA. “Other health impairment” is currently how APD is classified in NJ, in parallel with the 9th Circuit’s decision. This is an important decision for children suffering with APD because it allows children to access the types of services that would help them through an IEP or 504 Plan.
Conclusion
Prior to researching this topic for this class, my professional experience with children potentially being afflicted with APD was limited to performing a hearing screening and subsequently referring them to a physician for further assessment. This topic of study has interested me for quite some time and I have always been curious in how this type of disability would be addressed, more so now in contemplation of this class. We have discussed Auditory Processing Disorder in the context of several different areas of focus. Historically, the study of APD is relatively young with relation to other types of disabilities such as ADHD and Dyslexia. Moreover, it is important to understand the difficulty in diagnosis of APD. The comorbidity of APD with other disabilities like ADHD, Dyslexia and Autism makes it a challenge to isolate APD. Developing a course of “treatment” in the classical sense is also a challenge. For example, treating children with ADHD with stimulants may be a protocol that will prove useful in the child’s ability to get an education. With APD, there is no medical treatment. There is not one particular approach that works with every child. These interventions are tailored to specific children with individual considerations. When taking a systematic approach to addressing the ongoing needs of the child as they progress through the education system is a long term proposition. Curative measures are not possible with APD. Utilizing IEP and 504 Plans are the key to managing this disability over time in the educational environment. Reassessing goals in relation to progress is the key to an educational foundation for children that are challenged with Auditory Processing Disorder.