Publication Abstracts - 2004

Henry JA, Flick CL, Gilbert AM, Ellingson RM, Fausti SA. Comparison of manual and computer-automated procedures for tinnitus pitch-matching. Journal of Rehabilitation Research and Development, 41:121-138.

     Clinical assessment of tinnitus usually includes pitch-matching between the tinnitus and a pure tone.  Although such testing is performed routinely, response reliability has not been demonstrated yet.  The present study continues a series of studies designed to develop automated methodology for quantifying tinnitus perceptual characteristics.  Three methods for tinnitus pitch-matching were performed in a group of 42 subjects. Two methods were computed automated (Binary and Subject-Guided) and the third method was a traditional manual technique.  Each method provided excellent response reliability for about half of the subjects.  The most reliable subjects, however, differed widely between the different methods.  Each subject provided a total of 14 pitch matches using the three different methods.  Analyses based on each subject's total of 14 pitch matches revealed the range of pitch matches for each subject.  About half of the subjects selected pitch matches over a range of 2 1/3 octaves.  Results of this study suggest that specifying the range of tinnitus pitch matches rather than attempting to identify a single pitch match may be more appropriate.

Henry JA, Rheinsburg B, Zaugg T. Comparison of custom sounds for achieving tinnitus relief. Journal of the American Academy of Audiology, 2004. (In Press)

     Tinnitus Masking has been a widely used method for treating clinically significant tinnitus. The method, referred to herein as "sound-based relief," typically uses wearable ear-level devices ("maskers") to effect palliative tinnitus relief. Although often effective, this approach is limited to the use of broadband noise with the maskers. We hypothesized that the effectiveness of treatment can be improved by expanding the auditory-stimulus options available to patients. A pilot study was conducted to determine for each of 21 subjects the most effective of custom sounds that are designed to promote tinnitus relief. While sitting in a sound booth, subjects listened to white noise and to custom sounds that are available commercially for providing tinnitus relief. Three sound formats ("E-Water," "E-Nature" and "E-Air"), were provided by the Dynamic Tinnitus Mitigation (DTM-6a) system (Petroff Audio Technologies, Inc.) Additionally, seven sounds were provided by the Moses/Lang CD7 system (Oregon Hearing Research Center). Considering group data, all of the sounds provided a significant reduction in tinnitus annoyance relative to the annoyance of tinnitus alone. Two of the commercial sounds (DTM E-Nature and E-Water) were judged significantly more effective than the other sounds.

Lewis, M.S, Crandell, C., Valente, M., & Enrietto, J. Speech perception in noise: Directional microphones versus frequency modulation (FM) systems. Journal of the American Academy of Audiology,15:424-437.

     The major consequence of sensorineural hearing loss (SNHL) is communicative difficulty, especially with the addition of noise and/or reverberation.  The purpose of this investigation was to directly compare two types of technologies that have been shown to improve the speech-perception performance of individuals with SNHL: directional microphones and frequency modulation (FM) systems. Forty-six adult subjects with slight to severe SNHL served as subjects. Speech perception was assessed using the Hearing in Noise Test (HINT) with correlated diffuse noise under five different listening conditions.  Results revealed that speech perception was significantly better with the use of the FM system over that of any of the hearing aid conditions, even with the use of the directional microphone.  Additionally, speech perception was significantly better with the use of two hearing aids used in conjunction with two FM receivers rathe rthan with just one FM receiver.  Directional microphone performance was significantly better than omni-directional microphone performance. All aided listening conditions were significantly better than the unaided listening condition.

The National Center for Rehabilitative Auditory Research, Portland, Oregon 97207, USA. Gabrielle.Saunders@va.gov

OBJECTIVE: Measurement of hearing aid outcomes is necessary for demonstration of treatment efficacy, third-party payment, and cost-benefit analysis. Outcomes are usually measured with hearing-related questionnaires and/or tests of speech recognition. However, results from these two types of test often conflict. In this paper, we provide data from a new test measure, known as the Performance-Perceptual Test (PPT), in which subjective and performance aspects of hearing in noise are measured using the same test materials and procedures. A Performance Speech Reception Threshold (SRTN) and a Perceptual SRTN are measured using the Hearing In Noise Test materials and adaptive procedure. A third variable, the discrepancy between these two SRTNs, is also computed. It measures the accuracy with which subjects assess their own hearing ability and is referred to as the Performance-Perceptual Discrepancy (PPDIS). DESIGN: One hundred seven subjects between 24 and 83 yr of age took part. Thirty-three subjects had normal hearing, while the remaining seventy-four had symmetrical sensorineural hearing loss. Of the subjects with impaired hearing, 24 wore hearing aids and 50 did not. All subjects underwent routine audiological examination and completed the PPT and the Hearing Handicap Inventory for the Elderly/Adults on two occasions, between 1 and 2 wk apart. The PPT was conducted for unaided listening with the masker level set to 50, 65, and 80 dB SPL. RESULTS: PPT data show that the subjects with normal hearing have significantly better Performance and Perceptual SRTNs at each test level than the subjects with impaired hearing but that PPDIS values do not differ between the groups. Test-retest reliability for the PPT is excellent (r-values > 0.93 for all conditions). Stepwise multiple regression analysis showed that the Performance SRTN, the PPDIS, and age explain 40% of the variance in reported handicap (Hearing Handicap Inventory for the Elderly/Adults scores). More specifically, poorer performance, underestimation of hearing ability and younger age result in greater reported handicap, and vice versa. CONCLUSION: Reported handicap consists of a performance component and a (mis)perception component, as measured by the Performance SRTN and the PPDIS respectively. The PPT should thus prove to be a valuable tool for better understanding why some individuals complain of hearing difficulties but have only a mild hearing loss or conversely report few difficulties in the presence of substantial impairment. The measure would thus seem to provide both an explanation and a counseling tool for patients for whom there is a mismatch between reported and measured hearing difficulties.

Saunders, GH & Jutai JW (2004) Hearing specific and generic measures of the psychosocial impact of hearing aids. Journal of the American Academy of Audiology 15, 238-248.

National Center for Rehabilitative Auditory Research, 3710 SW US Veterans Hospital Road, Portland, OR 97207, USA. Gabrielle.saunders@va.gov

Hearing-specific and generic measures of hearing aid outcome were examined in order (a) to determine their relative sensitivity to hearing aid use and (b) to examine the relationship between pre-hearing aid use expectations and post-use outcomes. Ninety-two hearing-impaired individuals completed some combination of the Abbreviated Profile of Hearing Aid Benefit, Expected Consequences of Hearing Aid Ownership (ECHO), Satisfaction with Amplification in Daily Life (SADL), and Psychosocial Impact of Assistive Devices Scale, and provided reports of their daily and lifetime hearing aid use. In general, (a) the longer individuals wear hearing aids, the more positive the reported outcome, and (b) ECHO scores of non-hearing aid users are higher than SADL scores of new hearing aid users (six weeks to one year of use) but are similar to those obtained from experienced users (greater than one year of use). Between-questionnaire comparisons showed the generic measure to be as sensitive as the hearing aid specific measures. We suggest that generic measures have some advantages over hearing specific measures but that each has a place in the clinic.

Lewis, M.S., Crandell, C., & Kreisman, N. (2004). Effects of frequency modulation (FM) transmitter microphone setting on speech perception in noise. American Journal of Audiology, 13(1), 16-22.

Frequency modulation (FM) technology can significantly improve the speech perception ability of individuals with sensorineural hearing loss (SNHL) in background noise. Prior investigations have demonstrated that the microphone design of the FM transmitter can have a significant impact on this improved speech perception. The purpose of this investigation was to compare three types of FM transmitter microphone designs: (1) wide angle (omnidirectional microphone), which amplifies sounds coming from all directions around the microphone equally; (2) zoom (one directional microphone), which provides less amplification to signals coming from the rear and (3) superzoom (two directional microphones), which provides less amplification to signals originating from the rear and the sides. Fifteen adult subjects with bilateral slight to moderately-severe SNHL served as subjects. Speech perception was assessed using the Hearing in Noise Test (HINT). Speech spectrum shaped noise served as the noise competition. Results revealed that the best speech perception in noise was obtained when the FM transmitter was used in the zoom setting. The poorest performance was obtained when the FM transmitter was in the wide-angle mode. The clinical implications of these results are discussed.

Center for Research on Occupational and Environmental Toxicology, Oregon Health and Science University, Portland, OR 97201-3098, USA.

Neurobehavioral test batteries are often administered repeatedly to evaluate changes over time or effects of clinical interventions or neurotoxic exposures. Time intervals between test sessions range from very short (hours) to very long (decades). The aim of this study was to compare the impact of two brief time intervals on the test-retest reliability of frequently used neurobehavioral tests. Fifty healthy adults were recruited through newspaper advertisements in Portland, Oregon. Participants were divided into either a 6h (same-day) or 1-week retest group. All participants completed a battery of tests from the computerized Behavioral Assessment and Research System (BARS). Reliability was assessed by Pearson product-moment correlation and by intraclass correlation coefficient (ICC). The test battery generally showed adequate reliability in the short-term (week) and very short-term (day) and stability in performance over repeated administration when examined by multiple measures. Intraclass correlation coefficient ranged from 0.35 to 0.85. The magnitude of variation of performance in the administered tests was equally distributed around zero (i.e. no difference). The findings suggest that neurobehavioral tests such as BARS may be a useful tool for the assessment of acute exposures and clinical status where short-term evaluation is required (e.g. in the same-day or within 1 week).