Search

Many human subjects suffering from chronic tinnitus also suffer from hyperacusis, a heightened perception of loudness at moderate to intense sound levels. While numerous studies suggest that animals develop chronic tinnitus following intense noise exposure, it is not yet clear whether sound exposure also induces chronic hyperacusis-like responses in animals. We addressed this question by examining the chronic effects of intense sound exposure on the acoustic startle response (ASR) and its suppression by background noise containing brief gaps. We compared startle amplitudes in intense tone-exposed (10 kHz, 115 dB SPL, 4 h) and age-matched controls at 2–28 weeks post-exposure. While both groups showed similar startle thresholds, exposed animals showed a hyperacusis-like augmentation of ASR at high stimulus levels. Addition of background noise had little effect on ASR in controls but had a strong suppressive effect on startle in exposed animals, indicating a sensitization to background noise. When the background noise contained a gap preceding the startle stimulus, ASR was suppressed in control animals, but exposed animals showed a marked weakening of gap-induced suppression of ASR. This weakening of gap-induced startle suppression is consistent with the interpretation that the gap may have been masked by tinnitus. The associated hyper-responsiveness to startle stimuli presented alone and the sensitization to background noise suggest that hyperacusis may have also been induced. The results indicate that noise exposure leads to increases in the gain of auditory responsiveness and may offer a model of the association of hyperacusis with tinnitus.

There is a wide range of assessment techniques for tinnitus, but no consensus has developed concerning how best to measure either the presenting features of tinnitus or the effects of tinnitus treatments. Standardization of reliable and valid tinnitus measures would provide many advantages including improving the uniformity of diagnostic and screening criteria between clinics and facilitating comparison of treatment outcomes obtained at different sites. This chapter attempts to clarify issues involved in developing self-report questionnaires for the assessment of tinnitus. While the tinnitus questionnaires that are currently available provide valuable information on which to base diagnostic and screening decisions, they were not originally developed in such a way as to maximize their sensitivity to treatment-related changes in tinnitus. As a result, their construct validity for measuring treatment benefit has not received appropriate attention. In this paper, special emphasis is devoted to the use of effect sizes as an estimate of the ability of questionnaires (and their individual items) to measure changes associated with treatment. We discuss the criteria relevant to evaluating the effectiveness of a questionnaire for diagnostic purposes vs. for treatment-evaluation purposes, and we present a detailed illustration of how the various criteria have been applied in a recent questionnaire development effort.

The Three-Clinic Hearing Aid Selection Profile (HASP) was developed to assess a patient's beliefs about a number of basic considerations felt to be critical to the hearing aid selection (HAS) process. These characteristics are felt to be key to the acceptance of amplification and include motivation, expectations, cost of goods and services, appearance (cosmesis), attitudes about technology, physical function/limitations, communication needs, and lifestyle. The results of the first investigation suggest that we have been successful in developing a 40-item metric with adequate internal consistency reliability that assesses the aforementioned characteristics. Second, results of the administration of this tool to a large group of individuals indicated that (1) age impacted scores on the Technology, Physical Function, and Communicative Needs subscales; (2) gender impacted scores on the Motivation, Expectation, Technology, Communicative Needs, and Appearance subscales; (3) previous hearing aid use affected scores on the Motivation subscale; (4) level of education impacted scores on the Physical Function and Lifestyle subscales; and (5) self-perceived hearing handicap had an effect on Motivation and Communicative Needs subscale scores. Percentile data collected from this subject sample are presented as a benchmark against which to evaluate responses from individual patients. Case studies are presented to illustrate the potential clinical utility of this device.

This study assessed the test-retest reliability/repeatability and 95 percent confidence intervals (CIs) of the Tinnitus Handicap Inventory (THI) and developed categories for classifying self-perceived tinnitus handicap severity. Twenty-nine adults with tinnitus as their primary auditory complaint served as subjects. The THI was administered on two occasions (mean interval 20 days) using a paper-pencil format. Results support the contention that the THI is psychometrically robust. Specifically, the test-retest reliability/repeatability was high. Additionally, the 95 percent CI for the THI was 20-points, indicating that a 20-point or greater change had to occur from test to retest for a change to be considered statistically significant at the 5 percent confidence level. Quartiles calculated from raw scores were used to create a matrix of values representing tinnitus severity. We conclude that the THI is a brief, easily administered, and psychometrically robust measure that evaluates the impact of tinnitus on daily living.

To evaluate long-term hearing results and quality of life in patients with Ménière's disease.Detailed audiometric evaluation and disease-specific as well as global health quality evaluation of patients with Ménière's disease.Ambulatory evaluation was conducted in a large multispecialty clinic.Ménière's disease in only one ear, were at least 1 year posttreatment, were65 years of age, had no neurologic or psychologic disorders, and lived within driving distance of the ambulatory clinic.Audiometry, the Hearing Handicap Inventory, Dizziness Handicap Inventory, Tinnitus Handicap Inventory, and SF-36 Health Survey.No statistically significant differences in long-term hearing results were detected from natural history in medically or surgically treated patients with Ménière's disease. A significant disease-specific symptom handicap was detected. The global health handicap was greater for emotional disability than for physical disability.Medical and surgical treatment does not significantly influence hearing results in Ménière's disease. Patients with Ménière's disease have a greater emotional disability than a physical disability.

The mismatch negativity (MMN) was recorded from 10 young adults with normal hearing using naturally produced speech contrasts. Consonant-place and vowel-height contrasts were examined in consonant-vowel (CV) syllables by pairing either the consonant /t/ or /p/ with the vowel /I/ or /E/. Vowel-height was also examined as a pseudovowel; one cycle of the vowel segment of a CV was extracted and replicated over 200 msec. A total of five contrasts were examined: vowel-height following /p/, vowel-height following /t/, consonant-place preceding /E/, consonant-place preceding /I/, and pseudovowels. Significant MMN responses were elicited from all five contrasts, albeit with different amplitudes, latencies, and waveform morphology. The pseudovowel elicited the most well-defined MMN with the greatest amplitude and was found to be significantly different from the other four contrasts. Naturally produced speech stimuli appear to be viable stimuli for eliciting the MMN.

A 48-item questionnaire was administered to 100 older adults to determine their expectations regarding hearing aid use. The sample consisted of volunteers from a variety of senior citizen organizations and ranged in age from 55 to 92 years. Only individuals who reported no prior hearing aid usage were included in the sample. Expectations for the following factors were considered: cosmetics, acoustics, communication benefits, comfort, ease of use, cost and upkeep, and attitudes toward hearing aid use. In general, the older adults in this sample appeared to have very positive expectations regarding the use of hearing aids. Eighty-seven percent apparently have medium to high expectations for hearing aid use. Since the older adult's satisfaction with amplification may be influenced by original expectations and attitudes, the information provided in this study may be useful in improving the pre-fitting counseling of older hearing-impaired adults.