For anyone interested in the current state of research into hyperacusis, the newsletters are worth reading in detail. To give an idea of some of the leading medical scientists and their associated institutions working on hyperacusis research, here is an excerpt highlighting the summaries of a series of presentations at a recent conference.
Richard S. Tyler, Ph.D.
Professor of Otolaryngology
Carver College of Medicine, University of Iowa
Overviewed hyperacusis and its treatment from the patient’s and clinician’s perspective. A key point he noted was that while sound therapy and counseling can be helpful for some patients, at present there are no cures.
M. Charles Liberman, Ph.D.
Harold F. Schuknecht Professor of Otolaryngology
Harvard Medical School, Harvard University
Described the two types of “afferent” neurons that transmit signals from the cochlea: Type I neurons transmit information about sound; Type II neurons may be nociceptive (transmitters of pain signals). Type II dysfunction may underlie hyperacusis with pain, while differences in the Type I pathway may underlie differences in loudness discomfort.
Jaime Garcia-Añoveros, Ph.D.
Associate Professor of Anesthesiology and Neurology
Northwestern University
Led us further into the topic of auditory nociception and the biological research that has added to the theory that Type II cochlear neurons are pain receptors. He proposed that the auditory nociceptive system may trigger the pain sensation often associated with trauma-induced hyperacusis, since pain hyperacusis represents a pathological sensation akin to neuropathic pain.
Paul Fuchs, Ph.D.
John E. Bordley Professor and Vice-chair for Research in Otolaryngology
Johns Hopkins University School of Medicine
Showed us that damaged Type II neurons do not require an extremely loud sound stimulus to transmit “this hurts!” information to the central nervous system. Because these neurons are strongly activated when the outer hair cells are damaged, they may serve as the cochlea’s nociceptors.
Ulf Baumgaertner, M.D.
Chair of Neurophysiology, Center for Biomedicine and Medical Technology
Heidelberg University
Illuminated where in the brain sound and sound-related pain are processed, suggesting a way to visualize through fMRI what transpires in the brain during painful hyperacusis. When exposed to a painful auditory stimulus, the regions activated were those considered to be part of the nociceptive network in the brain.
Allan Basbaum, Ph.D.
Professor & Chair, Department of Anatomy
University of California, San Francisco
Suggested the pain of hyperacusis may be in part neuropathic. If true, this may allow us to tap into emerging major discoveries in treating this type of pain in patients with severe and disabling chronic pain. Some currently available pharmacological agents could be tested with hyperacusis patients.
