Better Together. March 13, 2012 Features: The ASHA Leader. by Tena McNamara & Gail Richard

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1 March 13, 2012 Features: The ASHA Leader Better Together by Tena McNamara & Gail Richard How do auditory processing disorders and deficits in language relate to one another if at all? It's a question that spurs endless debate. Some professionals believe that an auditory processing disorder (APD) is nothing more than a reflection of a language disorder or delay. Others believe true auditory processing difficulties exist that cause problems in language and academic skills. They point to neuroscience research that links auditory processing skills to sites in the central auditory nervous systems (e.g., Bamiou, Musiek, & Luxon, 2001; Musiek, Kibbe, & Baran, 1984; Musiek, Shinn Jirsa, Bamiou, Baran, & Zaidan, 2005). Abnormal functioning in these areas, it is theorized, can lead to an auditory processing deficit possibly triggering language and learning difficulties. What's challenging for professionals apart from the limited evidence to date on APD treatment efficacy (Fey et al., 2011, p. 254) is that listening and language skills can be difficult to tease apart in behavioral testing. For example, a problem with auditory input can compromise the linguistic signal, which in turn can cause problems in the development of vocabulary, syntax, and semantics. That said, we believe it is more productive to focus on addressing the effects of auditory weaknesses on school and home life than to expend energy debating whether poor performance on auditory skills tests reflects an auditory processing deficit or a language deficit. Audiologists are experts at investigating neurological components of auditory deficits. But when it comes to meeting a child's educational needs, information on functional performance will be needed. For example, behavioral tests for auditory processing often assess temporal processing defined as "the ability of the auditory system to represent and process changes in the acoustic signal that occur over time and to its ability to process brief transient acoustic events" (Banai & Kraus, 2007, p. 91). A child who performs poorly on temporal tasks may struggle to process rapid speech or longer segments of information presented auditorily. In such a case, a simple recommendation from the audiologist can make a big difference just decreasing the time and length of utterances, for example, may substantially boost that child's comprehension. Similarly, if a child scores poorly on behavioral tests for low redundancy speech, it is likely that poor classroom acoustics will impair that child's ability to interpret speech. Reducing excessive classroom noise and seating the child away from noise sources could help a great deal. Audiologists can and do offer such tips to teachers to help them improve children's comprehension of speech in the classroom. However, testing and intervention for APDs is not the sole domain of the audiologist. A speechlanguage pathologist also should be involved, providing key input on language abilities that may

2 be affected by deficits in auditory skills. Hence, intervention with APDs requires a close, ongoing collaboration between the SLP and the audiologist. What should that collaboration look like? We propose a model, but first we provide more justification. Why Collaborate? One major reason a cooperative model is so important is the large variability in how APDs affect children's language behaviors. It is inappropriate to make general judgments about a child's language skills based purely on auditory skills assessments. In turn, it is unrealistic to assume that poor performance on language tests means that the same would be true for performance on auditory processing tests. Problems can emerge if clinicians try to categorize or infer language and learning deficits based on results of the auditory processing evaluation alone. It is unrealistic to make recommendations for intervention based on a "profile" of the child, rather than by actually focusing on the child's unique needs. By involving the SLP, information on the child's language abilities and educational can be included in planning. While the audiologist identifies how deficits in auditory skills may affect language development, the SLP investigates effects of auditory deficits on actual language performance. Working together they can establish an intervention plan that better reflects the educational needs of the child. For a collaborative model to work efficiently, however, two aspects must be included: The SLP needs to incorporate multiple evaluation tools that address not only basic language skills, but also higher-level language function. As with any child who experiences auditory deficits (because of deafness, hearing loss, or auditory processing disorder), abstract language, critical thinking, and other language processing skills can pose challenges. Metalinguistic analysis may be affected due to difficulty applying the rules of language to auditory input. Also, testing should involve phonological/phonemic awareness skills, as problems with speech discrimination may correlate with abnormal auditory processes (Banai & Kraus, 2007). The audiologist also needs to employ multiple evaluation tools to ensure the accuracy of the diagnosis (Friberg & McNamara, 2010). Unfortunately, many tests have not been adequately assessed for their diagnostic accuracy and validity. An important consideration is the specific auditory challenges that children experience at home and in the classroom. Valid and reliable measures of auditory processing in natural environments are needed. No single assessment tool is likely sufficient for diagnostic decision-making. Rather, a variety of approaches should be used, including tests of dichotic listening, temporal processing/patterning, binaural interaction, and lowredundancy speech tasks (Musiek & Chermak, 2007). Collaboration with other professionals and the interpretation of multiple cross-check testing data (including those gathered from nonbehavioral tests), can help to yield a diagnosis.

3 An Ideal Partnership Based on the need for frequent communication between the audiologist and SLP, an effective diagnostic and intervention model for a child with a possible APD could look like this: The audiologist and SLP consult when the client is first referred. After reviewing the available case information, they can jointly identify possible deficits in areas such as phonology, semantics, syntax/morphology, reasoning, discourse, pragmatics, and literacy. Deficiencies in auditory skills would likely be reflected in one or more of these language areas. Based on their analysis, the SLP and audiologist should agree on the extent and type of testing needed. The audiologist evaluates the client and shares the results with the SLP. Functional performance on auditory tests may provide important insights into the deficits underlying disordered language performance. As explained by Richard (2007), the audiologist's role is to evaluate transmission of the acoustic signal through the peripheral and central auditory system, whereas the SLP's role is to explore problems in analyzing the acoustic signal to comprehend and respond. The SLP now assesses the specific language skills of the child, armed with the auditory skill performance data and the behavioral profile of language concerns. The SLP discusses results and intervention strategies with the audiologist and, based on the conversation, develops a tailor-made treatment plan to boost the child's performance in school and daily living. The plan should include measurements to assess academic and psychosocial progress. Given that electronic media now connect us, teamwork between audiologists and SLPs is always possible, even when they work at different sites. Ideally, audiologists who administer and interpret auditory processing assessments should forge relationships with local SLPs. Both professions need to understand the purpose of auditory processing assessment tools, the implications of test results for auditory skill performance, the purpose and implications of the various speech-language assessments, and the meaning of the results. Getting Connected With increased shared knowledge and collaboration between these professions, a child's auditory deficits can be addressed more efficiently and effectively. Both the audiologist and the SLP play an integral part in the diagnosis and treatment of children with these deficits, whether languageor auditory-related. Audiologists provide a unique perspective concerning why a child may not interpret auditory information accurately; SLPs increase awareness of how language skills are affected by the breakdown in auditory processing. As audiologists and SLPs, we address many disorders in which the true underlying etiology is a mystery. However, we still have a responsibility to treat the resulting deficits. It is time for each discipline to move beyond debating etiology issues. We should focus on working together to meet the pressing needs of children whose struggles to interpret and comprehend auditory information result in compromised academic performance.

4 Tena McNamara, AuD, CCC-A/SLP, is assistant professor in the Department of Communication Disorders and Sciences at Eastern Illinois State University and a member of ASHA's Special Interest Groups 9 (Hearing and Hearing Disorders in Children) and 10 (Issues in Higher Education). Contact her at tmcnamara@eiu.edu. Gail Richard, PhD, CCC-SLP, is professor and chair of the Department of Communication Disorders and Sciences at Eastern Illinois State University and ASHA vice president for speech-language pathology practice. Contact her at gjrichard@eiu.edu. cite as: McNamara, T. & Richard, G. (2012, March 13). Better Together. The ASHA Leader. References Banai, K., & Kraus, N. (2007). Neurobiology of (central) auditory processing disorder and language-based learning disability. In F. Musiek & G. Chermak (Ed.) Handbook of (central) auditory processing disorder: Auditory Neuroscience and Diagnosis. San Diego: Plural Publishing. Bocca, E. (1958). Clinical aspects of cortical deafness, Laryngoscope, 68, Bocca, E., & Calearo, C. (1963). Clinical aspects of cortical deafness. In J. Jerger (Ed.) Modern developments in audiology. New York: Academic Press. Bocca, E., Calearo, C., & Cassinari, V. (1954). A new method for testing hearing in temporal lobe tumor. Acta Otolaryngologica, 44, Bocca, E. Calearo, C., Cassinari, V., & Migliavacca, F. (1955). Testing "cortical hearing" in temporal lobe tumors. Acta Otolaryngologica, 42, Calearo, C., & Lazzaroni, A. (1957). Speech intelligibility in relation to the speech of the message. Laryngoscope, 67, Clarke, J. M., Lufkin, R. B., & Zaidel, E. (1993). Corpus callosum morphometry and dichotic listening performance: Individual differences in functional interhemispheric inhibition? Neuropsychologica, 31, Fey, M.E., Richard, G. J., Geffner, D., Kamhi, A.G., Medwetsky, L., Paul, D., Ross-Swain, D.,...Schooling, T. (2011). Clinical forum: The role of the speech-language pathologist in identifying and treating children with auditory processing disorder. Language, Speech, and Hearing Sciences in Schools, 42, Friberg, J. C., & McNamara, T. L. (2010). Psychometric validity of tests that assess central auditory processing abilities. Journal of Educational Audiology, 16,

5 Kimura, D. (1961). Some effects of temporal lobe damage on auditory perception. Canadian Journal of Psychology, 15, Musiek, F. E. (1983). Assessment of central auditory dysfunction: Dichotic Digits Test revisited, Ear and Hearing, 4, Musiek, F. E., & Chermak, G. D. (2007). Auditory neuroscience and (central) auditory processing disorder: An overview. In F. Musiek & G. Chermak (Ed.) Handbook of (central) auditory processing disorder: Auditory Neuroscience and Diagnosis. San Diego: Plural Publishing. Musiek, F. E., Kibbe, K., & Baran, J. (1984). Neuroaudiological results from split-brain patients. Seminars in Hearing, 5, Musiek, F. E., Shinn, J. B., Jirsa, R., Bamiou, D. E., Baran, J. A., & Zaidan, E. (2005). The GIN (Gaps-in-Noise) Test performance in subjects with confirmed central auditory nervous system involvement. Ear and Hearing, 26, Richard, G. J. (2007). Language processing versus auditory processing. In D. Geffner & D. Ross-Swain (Ed.) Auditory Processing Disorders: Assessment, Management, and Treatment. San Diego: Plural Publishing.