The primary aim of this research was to evaluate the validity, efficacy, and generalization of principles underlying a sound therapy-based treatment for promoting expansion of the auditory dynamic range (DR) for loudness. The basic sound therapy principles, originally devised for treatment of hyperacusis among patients with tinnitus, were evaluated in this study in a target sample of unsuccessfully fit and/or problematic prospective hearing aid users with diminished DRs (owing to their elevated audiometric thresholds and reduced sound tolerance). Secondary aims included: (1) delineation of the treatment contributions from the counseling and sound therapy components to the full-treatment protocol and, in turn, the isolated treatment effects from each of these individual components to intervention success; and (2) characterization of the respective dynamics for full, partial, and control treatments. Thirty-six participants with bilateral sensorineural hearing losses and reduced DRs, which affected their actual or perceived ability to use hearing aids, were enrolled in and completed a placebo-controlled (for sound therapy) randomized clinical trial. The 2 × 2 factorial trial design was implemented with or without various assignments of counseling and sound therapy. Specifically, participants were assigned randomly to one of four treatment groups (nine participants per group), including: (1) group 1-full treatment achieved with scripted counseling plus sound therapy implemented with binaural sound generators; (2) group 2-partial treatment achieved with counseling and placebo sound generators (PSGs); (3) group 3-partial treatment achieved with binaural sound generators alone; and (4) group 4-a neutral control treatment implemented with the PSGs alone. Repeated measurements of categorical loudness judgments served as the primary outcome measure. The full-treatment categorical-loudness judgments for group 1, measured at treatment termination, were significantly greater than the corresponding pretreatment judgments measured at baseline at 500, 2,000, and 4,000 Hz. Moreover, increases in their "uncomfortably loud" judgments (∼12 dB over the range from 500 to 4,000 Hz) were superior to those measured for either of the partial-treatment groups 2 and 3 or for control group 4. Efficacy, assessed by treatment-related criterion increases ≥ 10 dB for judgments of uncomfortable loudness, was superior for full treatment (82% efficacy) compared with that for either of the partial treatments (25% and 40% for counseling combined with the placebo sound therapy and sound therapy alone, respectively) or for the control treatment (50%). The majority of the group 1 participants achieved their criterion improvements within 3 months of beginning treatment. The treatment effect from sound therapy was much greater than that for counseling, which was statistically indistinguishable in most of our analyses from the control treatment. The basic principles underlying the full-treatment protocol are valid and have general applicability for expanding the DR among individuals with sensorineural hearing losses, who may often report aided loudness problems. The positive full-treatment effects were superior to those achieved for either counseling or sound therapy in virtual or actual isolation, respectively; however, the delivery of both components in the full-treatment approach was essential for an optimum treatment outcome.
Computer Graphics is evolving as a discipline characterized by the fusion of artistic and technical theories and skills. The goal of the SIGGRAPH Curriculum Working Group has been to create a knowledge base that defines this discipline. This knowledge base is presented as a palette of subject areas and skills that forms the necessary educational framework for creation of undergraduate curricula that specialize in computer graphics. It facilitates the development of attributes that will create paths toward professional work, graduate studies, and lifelong skills-development and learning focused on computer graphics. The details provided here are principally oriented toward faculty members designing new computer graphics programs or those evolving existing ones. They also benefit students who wish to craft their own programs in computer graphics, as well as administrators and accreditors seeking guidance for framing and assessing these programs.
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.
Strategies for treating hyperacusis, an anomolous condition of loudness perception, paradoxically seek either to minimize or enhance listeners’ sound exposures. We show that these reciprocal treatment approaches, implemented with similar amounts of background sound attenuation and enhancement, produce diametrically opposite perceptual effects in normal listeners. Specifically, we show after continuous, 2-week earplugging and low-level noise treatments that listeners become more and less sensitive, respectively, to the loudness of sounds. This simple demonstration of adaptive plasticity is consistent with modification of a theoretical gain control process, which is the basis for desensitizing sound therapies used in treating hyperacusis and related sound tolerance problems.
Hyperacusis is the intolerance to sound levels that normally are judged acceptable to others. The presence of hyperacusis (diagnosed or undiagnosed) can be an important reason that some persons reject their hearing aids. Tinnitus Retraining Therapy (TRT), a treatment approach for debilitating tinnitus and hyperacusis, routinely gives rise to increased loudness discomfort levels (LDLs) and improved sound tolerance. TRT involves both counseling and the daily exposure to soft sound from bilateral noise generator devices (NGs). We implemented a randomized, double-blind, placebo-controlled clinical trial to assess the efficacy of TRT as an intervention for reduced sound tolerance in hearing-aid eligible persons with hyperacusis and/or restricted dynamic ranges. Subjects were assigned to one of four treatment groups (2x2): Devices: NGs or placebo NGs and Counseling: Yes or No. They were evaluated at least monthly on a variety of audiometric tests, including LDLs, the Contour Test for Loudness for tones and speech, and word recognition measured at each session's comfortable and loud levels. Eighty percentage of the participants who received full treatment benefited significantly; whereas the other treatment groups demonstrated ≤ 45% treatment efficacy. Treatment dynamics and examples of improved word recognition post-treatment will be described. [Work supported by NIH R01 DC04678.]
