Ricky W. Burk
Dorothy Kelly, D.A.., CCC-S, is a speech-language pathologist and teacher of the hearing impaired with 28 years clinical and teaching experience. She is Chair of the Department of Speech Communication at St. Joseph's College in Patchogue, NY. Dr. Kelly is author of two books published by Communication Skill Builders: Auditory Processing Disorders: Strategies for Use with Children and Adolescents (1995), and A Winner's Workbook: Reproducible Activities for Children With ADD (1998). She also has an inservice program on Central Auditory Processing Disorder (CAPD) scheduled for publication in January 1999. She serves as editorial consultant and occasional contributor to Advance for Speech-Language Pathologists and Audiologists. Dr. Kelly has worked in schools, hospitals, and rehabilitation settings. Her undergraduate education focused on deaf education and elementary education; her Master's and doctoral work was in speech-language pathology.
RB: Dr. Kelly, would you give us your definition of central auditory processing disorder (CAPD)?
DK: The ASHA definition is very detailed, but a good way to summarize the definition of CAPD is to say that it involves a disorder of the interpretation of the verbal and nonverbal auditory stimuli. The person with CAPD has difficulty utilizing auditory information.
RB: Are there gender differences in patients with CAPD?
DK: Yes. Although we do not have a tremendous amount of data on the specifics, the caseloads are mostly male. The etiology of CAPD can range from traumatic brain injury (TBI) to malformation of the corpus callosum to lead poisoning, to chronic Otis media and many others. When we talk about malformation of the corpus callosum, then we are possibly on the track of talking about identifying gender differences. We know that the structure of the corpus callosum of the male is different from that of the female. In the normal individual, there are gender differences in terms of using the right and left hemispheres. It is possible that the corpus callosum is a part of the story in some cases; however, we certainly need additional research on this issue.
RB: How about age differences?
DK: Age is certainly a parameter in terms of remediation. I hesitate to use the term recovery because CAPD is not always a matter of catch-up. There is often a qualitative difference in an individual with CAPD. The younger child, especially before puberty, appears to respond to therapy better than children past puberty. A major factor here would be neural plasticity of the brain. In the older individual, there appears to be a degeneration of processing skills.
RB: So, would it be fair to say that there are two categories of CAPD: developmental and acquired?
DK: Yes. However, I believe that the term Central Auditory Processing Disorder is too amorphous. Perhaps we should have several categories of the disorder such as Central Auditory Processing Impairment, Central Auditory Processing Disorder, and Central Auditory Processing Delay, especially where the CAP is secondary to another disorder. I also think that we should have a term called Specific Central Auditory Processing Disorder to describe CAPD when it exists alone. CAPD exists in secondary form in the vast majority of cases. I think that is one of the main reasons that the incidence estimates we have are probably underestimated. In the school setting, for example, CAPD is frequently applied to an academic school setting, which does not deal with those terms. In the school, the primary diagnosis would be an educational diagnosis such as Attention Deficit Disorder, Learning Disability, and so forth. So, the diagnosis of CAPD may be missed because all symptoms are lumped together under one disorder.
RB: I understand you deal with five skill areas in CAPD. Could you describe those skill areas?
DK: I have been working on CAPD since about 1974. My first years in practice were spent as a teacher of the deaf. My first group of students was a group of Rubella children that first entered the school system in the early 1970s. It was apparent to me at that time there were kids with very similar audiograms that had very different uses of residual hearing and there appeared to be a mismatch between hearing and perception. I came across a wonderful book (Auditory Perceptual Disorders and Remediation; 1974, Springfield, IL: Charles C. Thomas) by Bernice Heasley. Heasley identified fourteen areas of processing skills. As I studied these fourteen areas, I began thinking of five key areas that impact on social and academic performance and that is how I developed my five skill areas. The first area I would mention is AUDITORY MEMORY. Auditory memory is often misunderstood and misdiagnosed, especially in schools. We tend to think of it as a generic skill involving repeating five numbers or five letters, or repeating a direction. If they repeat well, we tend to think that they have a good memory. Auditory memory if far more complex than that. It involves immediate as well as deferred memory. It also involves a variety of units. For example, a child may have good auditory memory for sentences, but not for numbers. We also tend to think that if a child has a good auditory memory, then the child should be able to carry out a direction. Carrying out a task involves far more than just rote recall of information. It involves an interpretation as well as an ability to carry out the direction. So, when we give a direction and ask the child to repeat the direction, we tend to assume that the child can carry out the task simply because the direction was repeated correctly. We know many children will be able to repeat a direction, but may have other programming problems (e.g., executive disfunction) that will inhibit or prevent them from actually carrying out the task. The second skill area is AUDITORY DISCRIMINATION. This is also an area that is underestimated in terms of its importance in the classroom. It impacts on following directions as well as spelling, reading, writing, and phonology skills. It is my belief that an auditory discrimination test should be a part of every reading program in schools. I feel that poor auditory discrimination is often a key factor when a child is not reading on target. There is a hierarchy involved in addressing auditory discrimination skills in therapy. Paula Tallal's work in the neurophysiological aspects of timing give us a lot of information on how to conceptualize a hierarchy for auditory discrimination tasks within a program. The third area is AUDITORY FIGURE-GROUND, which involves background noise. We know that auditory figure-ground in a normally developing child doesn't really mature until about age eight. If we have very noisy, unstructured, open classrooms in kindergarten through third grade, we may be asking a child to do more than he is capable of doing. Planning a program of intervention for the child with poor auditory figure-ground skills should start with building a tolerance for a variety of types and levels of noise and then having the child perform harder and harder tasks in those noises. We could begin with noise similar to that produced by an air-conditioner (white noise) and progress to a middle-ground type of noise that varies a little in frequency and volume but repeats a pattern, like the noise rain makes when falling or a dish-washer makes, and finally we could work with a cafeteria-type noise, noisy playground-type noise or the noisy classroom type noise, which is the most difficult type of noise to tolerate. Another factor that is not really auditory figure-ground, but is related to it is reverberation. We know that children don't do well perceiving speech within reverberant environments until as late as age thirteen. So, classroom acoustics is certainly something that we should be aware of and fine tune as far as possible. The fourth skill area, AUDITORY COHESION, is a higher order linguistic processing skill. It relates to such skills as complicated conversations as well as understanding jokes, riddles, inferences, and abstractions. It also impacts the child's ability to do note-taking. AUDITORY ATTENTION, the fifth skill area is the key skill. We come into the world with some ability to auditorily attend. We see in very young infants momentary attention to auditory stimuli. The auditory attention skill grows with maturation in the child. If there is delay in development of auditory attention, the everything else for the child is at risk in terms of performance in the classroom. Auditory attention is the glue that holds all the other auditory processing skills together. The skill areas are interrelated and hierarchial in nature. A child with CAPD may have any combination of difficulties to varying degrees of severity.
RB: Let's move to the topic of assessment of CAPD.
DK: The speech-language pathologist should certainly assess the five skill areas we just talked about and look at the impact of performance in those skill areas on spelling, reading, following directions, phonology, writing, vocabulary, and other language and language-dependent behaviors. Before I see a child for assessment, I send home a checklist for the parents. I have the teacher fill out a questionnaire on reading and a checklist of symptoms exhibited in the classroom. When I see the child, I will look at those five skill areas, and administer a reading decoding test. I think that how a child fails a task is just as important as what he fails. In spelling, for example, I am interested in the pattern of errors. Does he do better with sight vocabulary than with words with which he has to apply work-attack strategies? Does he do better with logically spelled words than with illogically spelled words? You can get a great deal of programming direction for intervention by observing the pattern of error in a variety of tasks. I typically spend two to two and a half hours of on-site testing. Following the formal assessment, I will spend six to seven hours putting the pieces of this assessment puzzle together and writing the report of six to seven pages. The issue of auditory discrimination is very important in the assessment. The possibility for a false negative on assessment of auditory discrimination is very real. If only the auditory discrimination subtest of the Test of Auditory Perceptual Skills (TAPS) is administered we could get the impression that the child's auditory discrimination is quite good. If we compare the performance on auditory discrimination subtest of the TAPS, which involves only auditory stimuli, with another test that involves visual stimuli (e.g., Goldman-Fristoe Woodcock Test of Auditory Discrimination) we may see many children who will do very well on the TAPS, but very poorly on the Goldman-Fristoe Woodcock. This may mean that the child has good auditory discrimination, but poor auditory-visual integration discrimination. I feel that some children with CAPD have hidden auditory-visual integration difficulties. The assessment of a child with CAPD is not a formula, not a specific protocol. Assessment involves looking at the relationship between the child's performance and the impact of auditory processing skills on that performance. Audiological evaluation must precede all assessment. CAPD assessment by both an audiologist and a speech-language pathologist is ideal. I also feel that screening for CAPD should be completed at the preschool or kindergarten level.
Dr. Kelly will appearing at the 1999 MSHA Annual Continuing Education Conference in a six-hour presentation on Central Auditory Processing Disorder. You may contact Dr. Dorothy Kelly at 44 Long Meadow Place, S. Setauket, NY 11720
