ABSTRACT
A vexing problem in audiology has been the modification of sound tolerance. Sound
intolerance and restricted dynamic ranges are common conditions that audiologists
encounter daily in the hearing-impaired population, especially in the fitting of hearing
aids. To date, no clinical protocol has proven to be successful for modifying sound
tolerance among the hearing- impaired population. This report describes the use of
low-level, broadband sound in a habituation-based treatment protocol termed Tinnitus
Retraining Therapy (TRT). Over the past decade, TRT has become increasingly popular
as an intervention for severe tinnitus and hyperacusis. One of the primary treatment
effects from TRT is that over the course of the intervention the patient's loudness
discomfort level (LDL) thresholds routinely shift to higher levels. Ostensibly, the
resulting higher LDL thresholds reflect treatment effects associated with the resetting
of a plastic and adaptive auditory gain process that somehow regulates the supra-threshold
sensitivity of the auditory system in response to chronic changes in the sound input
from the auditory periphery to the central auditory pathways. Tinnitus patients with
significant hearing losses and sound tolerance problems respond successfully to TRT
and, as a consequence, their LDL thresholds are usually elevated (improved) and, concomitantly,
their dynamic ranges are expanded. Many of these patients, who before the TRT intervention
could not tolerate amplified sound, then have been able to make a comfortable transition
into appropriate amplification after treatment. In principle, TRT would seem to offer
a viable intervention strategy for modifying sound tolerance in the general hearing-impaired
population. If so, then the clinical applications of TRT principles may extend well
beyond the treatment of tinnitus and hyperacusis.
KEYWORD
Sound tolerance - hyperacusis - Tinnitus Retraining Therapy - chronic auditory gain
- adaptive plasticity
