Proceedings of the 5th International NCRAR Conference—Expanding Our Horizons: Medical Conditions and Audiology

This issue of Seminars in Hearing consists of articles that arose from the 5th National Center for Rehabilitative Auditory Research (NCRAR) biennial conference “Expanding Our Horizons: Medical Conditions and Audiology” that took place in Portland, Oregon, on October 12 to 14, 2011, and was attended by ~160 clinicians, scientists, educators, and students from around the United States and abroad. The NCRAR hosts an international conference every 2 years, bringing together clinical researchers and practicing audiologists to our mutual benefit in an interactive format with the goal of translating research findings into practice.

The objective of this particular conference was to expand knowledge and understanding of the interactions between the auditory system and other medical conditions and how these impact auditory intervention and rehabilitation because, for optimal function, the auditory system requires intact physiological systems throughout the body. Conditions that affect the vascular, endocrine, immune, and nervous systems also can detrimentally affect auditory system function,[1] [2] [3] [4] and the prevalence of such pathologies, such as autoimmune disease, multiple sclerosis, and diabetes, are rapidly increasing.[5] [6] Furthermore, with the aging of the population, the prevalence of stroke and dementia also is increasing.[7] [8] Clinicians need to consider these conditions during patient evaluations and be aware of the challenges posed by these factors to select the most effective methods for rehabilitation.[9] Likewise, scientists need to be aware of the clinical issues these patients present to target research that can be translated from the laboratory into clinical practice.

Our invited speakers gave podium presentations at the conference on a variety of these topics, including effects of hormones on auditory functions; epidemiological factors associated with hearing loss and tinnitus; interactions between cognitive function and auditory processing; immune-mediated inner ear disease and hearing loss; effects of drug abuse on auditory and vestibular functions; auditory processing in patients with multiple sclerosis; and auditory hallucinations.

The main conference began with a keynote address by Dr. Karen Cruickshanks. She engaged the audience with her description of epidemiological evidence suggesting that hearing loss may signal risk for negative psychological impacts and that there are unmet needs for hearing screening and hearing healthcare. Thursday's session began with a welcome from Dr. Patrick Feeney, the Director of the NCRAR, followed by fascinating presentations from Drs. Bob Frisina and Richard Smith. Dr. Frisina presented data showing that hormone replacement therapy and testosterone can diminish peripheral and central auditory function, and Dr. Smith described how phenomic data on hearing complement genomic data. He also discussed current genetic counseling practices for disorders and conditions that affect hearing. Thursday's presentations continued with the NCRAR multiple sclerosis research team (Drs. M. Samantha Lewis, Bob Folmer, and Bill Rooney) and inner ear disease expert Dr. Dennis Trune. We learned that behavioral, electrophysiological, and imaging data show multiple sclerosis to be associated with dysfunction of auditory pathways, and from Dr. Trune we learned about the current theories of mechanisms and treatments for autoimmune hearing loss.

Dr. Ivan Lopez opened Friday's presentations with an overview of hearing loss and vestibular dysfunction due to abuse of drugs, including opiates. This was followed by Dr. Nina Dronkers' superb presentation on neural correlates of auditory comprehension deficits in stroke patients. She demonstrated the utility of new imaging techniques for localizing brain damage, and she used patient videos to illustrate how stroke-related damage impacts both speech understanding and production. The final presentations of the meeting were from Drs. George Gates and Cynthia Wible. Dr. Gates described his findings that show an association between central auditory processing deficits and dementia, and Dr. Wible explained her new model of auditory hallucinations, including the brain regions hypothesized to generate these abnormal perceptions.

The conference ended with a roundtable discussion of the concepts that our speakers raised during their talks. We were honored to have as members of the panel Dr. Patricia Dorn, Interim Director of Veterans Affairs (VA) Rehabilitation Research and Development Service; Dr. Stephen Fausti, Founder and Retired Director of NCRAR; Dr. Victoria Keetay, Director, School of Audiology at Pacific University; and Lt. Col. Dr. Mark Packer, Interim Director of the Department of Defense Hearing Center of Excellence. The audience especially enjoyed the fact that all of the presenters provided clinical recommendations based on their specialized research.

We thank the speakers who generously shared the content of their talks in this special issue of Seminars in Hearing, and all who participated in conference planning and organization, as well as our sponsors: National Institutes of Health–National Institutes on Deafness and Other Communication Disorders; VA Rehabilitation Research and Development Service; GNResound; Oticon; Etymotic Research Inc.; Phonak; and Frye Electronics Inc. for their generous support of this meeting. The VA Employee Education System (EES) professionally videoed the conference; the presentations have been broadcast through the Veterans Affairs Knowledge Network system. Conference DVDs prepared by EES can be obtained from the NCRAR on request.

By publishing this special issue of Seminars in Hearing, our goal is to raise awareness among hearing health clinicians and researchers about medical conditions that affect hearing and auditory processing and to raise awareness that patients' hearing and central auditory functions should be considered and assessed during the course of treatment or study. We hope these efforts will facilitate advancements in clinical research methods, patient assessment, and treatment protocols that will contribute to improvements in auditory rehabilitation.

• References

• 1 Al-Mana D, Ceranic B, Djahanbakhch O, Luxon LM. Hormones and the auditory system: a review of physiology and pathophysiology. Neuroscience 2008; 153: 881-900
• 2 Frisina RD. Age-related hearing loss: ear and brain mechanisms. Ann N Y Acad Sci 2009; 1170: 708-717
• 3 Hull RH, Kerschen SR. The influence of cardiovascular health on peripheral and central auditory function in adults: a research review. Am J Audiol 2010; 19: 9-16
• 4 Ryan AF, Pak K, Low W , et al. Immunological damage to the inner ear: current and future therapeutic strategies. Adv Otorhinolaryngol 2002; 59: 66-74
• 5 Mozumdar A, Liguori G. Persistent increase of prevalence of metabolic syndrome among US adults: NHANES III to NHANES 1999–2006. Diabetes Care 2010; 34: 216-219
• 6 U.S. Department of Health and Human Services. Biennial Report of the Director, NIH FY2006 & 2007 Summary of Research Activities by Disease Categories. Autoimmune Diseases. 2007. Updated October 19, 2010. Available at: http://report.nih.gov/biennialreport0607/research_activities_by_disease_categories/autoimmune_diseases.aspx?SID=24 . Accessed November 15, 2010
• 7 James BD, Schneider JA. Increasing incidence of dementia in the oldest old: evidence and implications. Alzheimers Res Ther 2010; 2: 9
• 8 Centers for Disease Control and Prevention (CDC). State-specific mortality from stroke and distribution of place of death—United States, 1999. MMWR Morb Mortal Wkly Rep 2002; 51: 429-433
• 9 Palmer CV, Adams SW, Bourgeois M, Durrant J, Rossi M. Reduction in caregiver-identified problem behaviors in patients with Alzheimer disease post-hearing-aid fitting. J Speech Lang Hear Res 1999; 42: 312-328