Effects of Various Extents of High-Frequency Hearing Loss on Speech Recognition and Gap Detection at Low Frequencies in Patients with Sensorineural Hearing Loss.

This study explored whether the time-compressed speech perception varied with the degree of hearing loss in high-frequency sensorineural hearing loss (HF SNHL) individuals. 65 HF SNHL individuals with different cutoff frequencies were recruited and further divided into mildly, moderately, and/or severely affected subgroups in terms of the averaged thresholds of all frequencies exhibiting hearing loss. Time-compressed speech recognition scores under both quiet and noisy conditions and gap detection thresholds within low frequencies that had normal thresholds were obtained from all patients and compared with data from 11 age-matched individuals with normal hearing threshold at all frequencies. Correlations of the time-compressed speech recognition scores with the extents of HF SNHL and with the 1 kHz gap detection thresholds were studied across all participants. We found that the time-compressed speech recognition scores were significantly affected by and correlated with the extents of HF SNHL. The time-compressed speech recognition scores also correlated with the 1 kHz gap detection thresholds except when the compression ratio of speech was 0.8 under quiet condition. Above all, the extents of HF SNHL were significantly correlated with the 1 kHz gap thresholds.

Laboratory evaluation of an optimised internet-based speech-in-noise test for occupational high-frequency hearing loss screening: Occupational Earcheck.

OBJECTIVE: The "Occupational Earcheck" (OEC) is a Dutch online self-screening speech-in-noise test developed for the detection of occupational high-frequency hearing loss (HFHL). This study evaluates an optimised version of the test and determines the most appropriate masking noise. DESIGN: The original OEC was improved by homogenisation of the speech material, and shortening the test. A laboratory-based cross-sectional study was performed in which the optimised OEC in five alternative masking noise conditions was evaluated. STUDY SAMPLE: The study was conducted on 18 normal-hearing (NH) adults, and 15 middle-aged listeners with HFHL. RESULTS: The OEC in a low-pass (LP) filtered stationary background noise (test version LP 3: with a cut-off frequency of 1.6 kHz, and a noise floor of -12 dB) was the most accurate version tested. The test showed a reasonable sensitivity (93%), and specificity (94%) and test reliability (intra-class correlation coefficient: 0.84, mean within-subject standard deviation: 1.5 dB SNR, slope of psychometric function: 13.1%/dB SNR). CONCLUSIONS: The improved OEC, with homogenous word material in a LP filtered noise, appears to be suitable for the discrimination between younger NH listeners and older listeners with HFHL. The appropriateness of the OEC for screening purposes in an occupational setting will be studied further.

Health-related quality of life and mental distress in patients with partial deafness: preliminary findings.

The aim of the study was to evaluate mental distress and health-related quality of life in patients with bilateral partial deafness (high-frequency sensorineural hearing loss) before cochlear implantation, with respect to their audiological performance and time of onset of the hearing impairment. Thirty-one patients and 31 normal-hearing individuals were administered the Beck Depression Inventory (BDI), the State-Trait-Anxiety-Inventory (STAI) and the World Health Organization Quality of Life-BREF questionnaire (WHOQOL-BREF). Patients also completed the Nijmegen-Cochlear-Implant-Questionnaire (NCIQ), a tool for evaluation of quality of life related to hearing loss. Patients revealed increased depressive and anxiety symptoms, as well as decreased health-related quality of life (psychological health, physical health), in comparison with their healthy counterparts (t tests, p < 0.05). Furthermore, a General Linear Model demonstrated in patients with a prelingual onset of hearing loss enhanced self-evaluated social interactions and activity (NCIQ), when their outcomes were contrasted with those obtained in individuals with postlingual partial deafness (p < 0.05). The study failed to show any effect of collateral tinnitus. Patients not using hearing aids had better audiological performance and, therefore, better sound perception and speech production, as measured with NCIQ. There was no effect of hearing aid use with respect to mental distress. Additional statistically significant correlations seen in patients included those between a steeper slope hearing loss configuration (averaged pure-tone thresholds at 1 and 2 kHz with subtracted threshold at 0.5 kHz) and better audiometric speech detection, between audiometric thresholds and the subjectively rated sound perception (NCIQ), as well as left-ear audiometric word recognition scores and the subjectively perceived ability to recognize advanced sounds (NCIQ). In addition, a longer duration of postlingual deafness, as well as a younger age at the onset were both related to worse speech detection thresholds. The results of the study provide evidence that successful rehabilitation in patients with partial deafness might have to go beyond the standard speech therapy. Enhancement of the regular diagnostic assessment with additional psychological tools is highly recommended. Further investigation is required as to the role of functional residual hearing, hearing aid use and tinnitus, in relation to future outcomes of cochlear implantation.

The effects of frequency lowering on speech perception in noise with adult hearing-aid users.

OBJECTIVE: Frequency lowering (FL) strategies move high frequency sound into a lower frequency range. This study determined if speech perception differences are observed between some of the different frequency lowering strategies that are available. DESIGN: A cross-sectional, repeated-measures design was used to compare three hearing aids that used wide-dynamic range compression (WDRC) and either non-linear frequency compression (NFC), linear frequency transposition (LFT), or frequency translation (FT). The hearing aids were matched to prescriptive real ear targets for WDRC. The settings for each FL strategy were adjusted to provide audibility for a 6300 Hz filtered speech signal. Sentence recognition in noise, subjective measures of sound quality, and a modified version of the speech intelligibility index (SII) were measured. STUDY SAMPLE: Ten adults between the ages of 63 to 82 years with bilateral, high frequency hearing loss. RESULTS: LFT and FT led to poorer sentence recognition compared to WDRC for most individuals. No difference in sentence recognition occurred with and without NFC. The quality questionnaire and SII showed few differences between conditions. CONCLUSION: Under similar fitting and testing conditions of this study, FL techniques may not provide speech understanding benefit in certain background noise situations.

Benefit from non-linear frequency compression hearing aids in a clinical setting: the effects of duration of experience and severity of high-frequency hearing loss.

OBJECTIVES: To determine whether non-linear frequency compression (NLFC) is effective for hearing-impaired adults in a clinical setting. To determine whether benefit from NLFC is related to duration of NLFC experience or severity of high-frequency hearing loss. DESIGN: Participants were fitted with Phonak frequency compression hearing aids as part of their standard clinical care, using the manufacturer's default fitting settings. Participants had been using NLFC for between 1 and 121 weeks at the time of testing. Speech recognition thresholds in noise and consonant recognition in quiet were measured with and without NLFC enabled. STUDY SAMPLE: Forty-six experienced adult hearing-aid users. RESULTS: Consonant recognition in quiet, but not speech recognition in noise was significantly better with NLFC enabled. There was no significant correlation between duration of frequency compression experience and benefit. Benefit for consonant recognition was negatively correlated with mean audiometric thresholds from 2-6 kHz. CONCLUSIONS: NLFC was beneficial for consonant recognition but not speech recognition in noise. There was no evidence to support the idea that a long period of acclimatization is necessary to gain full benefit. The relation between benefit and high-frequency thresholds might be explained by the poor audibility of compressed information for some listeners with severe loss.

Frequency discrimination in ears with and without contralateral cochlear dead regions.

OBJECTIVE: The purpose of this study was to test the ability to discriminate low-frequency pure-tone stimuli for ears with and without contralateral dead regions, in subjects with bilateral high-frequency hearing loss; we examined associations between hearing loss characteristics and frequency discrimination of low-frequency stimuli in subjects with high-frequency hearing loss. DESIGN: Cochlear dead regions were diagnosed using the TEN-HL test. A frequency discrimination test utilizing an adaptive three-alternative forced choice method provided difference limens for reference frequencies 0.25 kHz and 0.5 kHz. STUDY SAMPLE: Among 105 subjects with bilateral high-frequency hearing loss, unilateral dead regions were found in 15 subjects. These, and an additional 15 matched control subjects without dead regions, were included in the study. RESULTS: Ears with dead regions performed best at the frequency discrimination test. Ears with a contralateral dead region performed significantly better than ears without a contralateral dead region at 0.5 kHz, the reference frequency closest to the mean audiogram cut-off, while the opposite result was obtained at 0.25 kHz. CONCLUSIONS: Results may be seen as sign of a contralateral effect of unilateral dead regions on the discrimination of stimuli with frequencies well below the audiogram cut-off in adult subjects with bilateral high-frequency hearing loss.

Hearing impairment and self-masking: listening during vocalization.

OBJECTIVES: To describe the masking effect of a vocalized [a:] on noise bands and speech in persons with mild-to-moderate hearing impairment (HI). DESIGN: The masked threshold of noise bands (250-8000 Hz), continuous discourse, and the amount of masking produced were determined. The maximal vocalization level was determined, that still allowed the subject to just follow the continuous discourse. STUDY SAMPLE: Twenty persons with sensory-neural HI, twelve with a high-frequency (HF) loss and eight with low-, mid-frequency or flat (LMF) loss. RESULTS: The [a:] gave a significantly higher masked threshold at 70 and 80 dBA vocalization for subjects with HF loss than for normal-hearing (NH) subjects, and somewhat higher thresholds than for those with LMF loss. The amount of masking produced was significantly smaller for subjects with HI than NH. CONCLUSIONS: It is important to consider masking effects of self-produced sounds in auditory rehabilitation, and in the future design of hearing aids.

Hearing aid outcomes for listeners with high-frequency hearing loss.

PURPOSE: To determine whether listeners with primarily high-frequency sensorineural hearing loss (HF SNHL) perceived benefit from amplification provided by completely-in-the-canal (CIC) hearing aids. METHOD: The Hearing Handicap for the Elderly-Screening version, the Abbreviated Profile of Hearing Aid Benefit, and the Satisfaction With Amplification in Daily Life questionnaires were mailed to 2 groups of listeners (n = 79) who matched preset criteria, including threshold at 2000 Hz and use of CIC amplification. Sixty-seven percent (n = 53) of the questionnaires were returned and were divided into 2 groups. Group I (n = 26) consisted of listeners with normal hearing through 2000 Hz, and Group II (n = 27) consisted of listeners with normal hearing only through 1000 Hz. RESULTS: Results revealed that both groups perceived significant hearing handicap, hearing aid benefit, and hearing aid satisfaction. Differences between the 2 groups on the 3 measures, however, were not statistically significant. CONCLUSIONS: Listeners with HF SNHL perceived benefit and satisfaction from amplification with CIC hearing aids. Individuals with SNHL limited to the high frequencies should be considered candidates for amplification.

Effect of minimal hearing loss on children's ability to multitask in quiet and in noise.

PURPOSE: The purpose of the present study was to examine the effect of minimal hearing loss (HL) on children's ability to perform simultaneous tasks in quiet and in noise. METHOD: Ten children with minimal HL and 11 children with normal hearing (NH) participated. Both groups ranged in age from 8 to 12 years. The children categorized common words (primary task) while completing dot-to-dot games (secondary task) in quiet as well as in noise presented at 0 dB and +6 dB signal-to-noise ratios (SNRs). It was hypothesized that the children's progression through the dot-to-dot games would slow as they encountered more difficult listening environments. This hypothesis was based on the theory that listeners have limited cognitive resources to allocate to any combination of tasks. RESULTS: The dot rate of both groups decreased similarly in the multitasking conditions relative to baseline. However, no other differences between groups or listening conditions were revealed. Significantly poorer word categorization was observed for the children with minimal HL in noise. CONCLUSION: These data suggest that children with minimal HL may be unable to respond to a difficult listening task by drawing resources from other tasks to compensate.

Declining and fluctuating prevalence values of hearing impairment in 18-year old Swedish men during three decades.

OBJECTIVE: To analyze time trends in prevalence of hearing impairment in almost complete birth cohorts of 18-year old Swedish men from 1970s up to 2010. STUDY GROUPS: Before 1999, all 18-year old men, in Sweden, were called for a compulsory conscription examination. In 1971-1999, the participation rate in audiometry was 73-95%. After 1999, when exemption from conscription was allowed, the participation rate gradually declined to 52% in 2004. Samples with participation rates below 50% (2005-2010) were considered non-representative and excluded from the analyses. RESULTS: High-frequency hearing impairments (HFHI) 35-40 dB HL and ≥45 dB HL showed a decreasing trend over the observed period, from a prevalence of 2.9% (35-40 dB HL) and 3.8% (≥45 dB HL) respectively in 1971 to 1.4% and 1.1% respectively in 2004. HFHI 25-30 dB HL, showed slow variations over time and decreased from 8.5% in 1971 to 3.2% in 1981 followed by an increase to 10.4% in 1992. After that year there was a decrease to 5.2% in 2004. The slow fluctuations affected only HFHI 25-30 dB HL, mainly at 6 kHz. The left ear was more affected than the right ear. CONCLUSIONS: The most important observation was a decrease of HFHI 35-40 dB HL by 52% percent and of HFHI ≥45 dB HL by 71% between the years 1971 and 2004. The prevalence of HFHI 25-30 dB HL in young Swedish males fluctuated over a period of 33 years. Possible reasons for these trends and variations are discussed.

Cochlear Implantation in Children with Postlingual Progressive Steeply Sloping High-Frequency Hearing Loss.

BACKGROUND: Children with steeply sloping sensorineural hearing loss (SNHL) lack access to critical high-frequency cues despite the use of advanced hearing aid technology. In addition, their auditory-only aided speech perception abilities often meet Food and Drug Administration criteria for cochlear implantation. PURPOSE: The objective of this study was to describe hearing preservation and speech perception outcomes in a group of young children with steeply sloping SNHL who received a cochlear implant (CI). RESEARCH DESIGN: Retrospective case series. STUDY SAMPLE: Eight children with steeply sloping postlingual progressive SNHL who received a unilateral traditional CI at Seattle Children's Hospital between 2009 and 2013 and had follow-up data available up to 24 mo postimplant were included. DATA COLLECTION AND ANALYSIS: A retrospective chart review was completed. Medical records were reviewed for demographic information, preoperative and postoperative behavioral hearing thresholds, and speech perception scores. Paired t tests were used to analyze speech perception data. Hearing preservation results are reported. RESULTS: Rapid improvement of speech perception scores was observed within the first month postimplant for all participants. Mean monosyllabic word scores were 76% and mean phoneme scores were 86.7% at 1-mo postactivation compared to mean preimplant scores of 19.5% and 31.0%, respectively. Hearing preservation was observed in five participants out to 24-mo postactivation. Two participants lost hearing in both the implanted and unimplanted ear, and received a sequential bilateral CI in the other ear after progression of the hearing loss. One participant had a total loss of hearing in only the implanted ear. Results reported in this article are from the ear implanted first. Bilateral outcomes are not reported. CONCLUSIONS: CIs provided benefit for children with steeply sloping bilateral hearing loss for whom hearing aids did not provide adequate auditory access. In our cohort, significant improvements in speech understanding occurred rapidly postactivation. Preservation of residual hearing in children with a traditional CI electrode is possible.

Prevalence of Hearing Loss in Teachers of Singing and Voice Students.

OBJECTIVES: Singers and voice teachers are exposed to a range of noise levels during a normal working day. This study aimed to assess the hearing thresholds in a large sample of generally healthy professional voice teachers and voice students to determine the prevalence of hearing loss in this population. STUDY DESIGN: A cross-sectional study was carried out. METHODS: Voice teachers and vocal students had the option to volunteer for a hearing screening of six standard frequencies in a quiet room with the Shoebox audiometer (Clearwater Clinical Limited) and to fill out a brief survey. Data were analyzed for the prevalence and severity of hearing loss in teachers and students based on several parameters assessed in the surveys. All data were analyzed using Microsoft Excel (Microsoft Corp.) and SPSS Statistics Software (IBM Corp.). RESULTS: A total of 158 participants were included: 58 self-identified as voice teachers, 106 as voice students, and 6 as both. The 6 participants who identified as both, were included in both categories for statistical purposes. Of the 158 participants, 36 had some level of hearing loss: 51.7% of voice teachers had hearing loss, and 7.5% of voice students had hearing loss. Several parameters of noise exposure were found to positively correlate with hearing loss and tinnitus (P < 0.05). Years as a voice teacher and age were both predictors of hearing loss (P < 0.05). CONCLUSIONS: Hearing loss in a cohort of voice teachers appears to be more prevalent and severe than previously thought. There is a significant association between years teaching and hearing loss. Raising awareness in this population may prompt teachers and students to adopt strategies to protect their hearing.

Neuromagnetic indicators of auditory cortical reorganization of tinnitus.

Animal studies show that following damage to inner-ear receptors, central representations of intact lesion-edge (LE) frequencies become enlarged (map reorganization). One theory of tinnitus holds that this process could be related to the tinnitus sensation. To test this hypothesis, neuromagnetic evoked fields of tinnitus participants with high-frequency hearing loss and normal hearing controls were measured, while subjects listened to monaurally presented LE or control (CO; an octave below LE) tones. The predictions made based on the map reorganization hypothesis of tinnitus were that neuronal responses to LE frequencies would be enhanced, and that source localizations for LE would be distorted. N1m equivalent dipole moments for LE were not supranormal in the tinnitus group, whereas responses to CO of tinnitus patients compared to controls were enlarged in the right hemisphere. This effect was positively associated with tinnitus-related distress. Abnormal source locations were found for generators activated by LE tones in the right hemisphere of the tinnitus group. This right-hemispheric map distortion was not associated with subjective variables of tinnitus. A positive correlation with tinnitus distress was found for the left hemisphere with more anterior sources being associated with enhanced distress. However, this result was independent of the frequency of the stimulus. Overall, the present study suggests that mechanisms of map reorganization, although present in the data, cannot satisfactorily explain the emergence of tinnitus and that differential hemispheric involvement must be considered.

Harmonic Frequency Lowering: Effects on the Perception of Music Detail and Sound Quality.

A novel algorithm for frequency lowering in music was developed and experimentally tested in hearing-impaired listeners. Harmonic frequency lowering (HFL) combines frequency transposition and frequency compression to preserve the harmonic content of music stimuli. Listeners were asked to make judgments regarding detail and sound quality in music stimuli. Stimuli were presented under different signal processing conditions: original, low-pass filtered, HFL, and nonlinear frequency compressed. Results showed that participants reported perceiving the most detail in the HFL condition. In addition, there was no difference in sound quality across conditions.

Factors affecting psychophysical tuning curves for hearing-impaired subjects with high-frequency dead regions.

A dead region (DR) is a region of the cochlea where there are no functioning inner hair cells and/or neurons. DRs can be detected using the threshold-equalizing-noise (TEN) test, but psychophysical tuning curves (PTCs) are sometimes used to give a more precise estimate of the edge frequency of a DR; a shifted tip of the PTC indicates a DR. We show here that the shapes of PTCs for hearing-impaired subjects can be influenced by the detection of beats and simple difference tones (SDTs). As a result, PTCs can have tips at f(s), even when f(s) falls in a DR. PTCs were measured for subjects with mild to moderate low-frequency and severe high-frequency hearing loss using sinusoidal and narrowband noise maskers (80-, 160-, 320-Hz wide): (1) in quiet; (2) in the presence of additional lowpass filtered noise (LF noise) designed to mask SDTs; (3) in the presence of a pair of low-frequency tones designed to interfere with the detection of beats (MDI tones). In condition (1), the PTCs were often W-shaped, with a sharp tip at f(s). This occurred less for the wider noise bandwidths. For subjects with good low-frequency hearing, the LF noise often reduced or eliminated the tip at f(s), suggesting that this tip was partly caused by detection of SDTs. For the sinusoidal and 80-Hz wide noise maskers, the addition of the MDI tones reduced the masker level required for threshold for masker frequencies adjacent to f(s), for nearly all subjects, suggesting a strong influence of beat detection. To minimize the influence of beats, we recommend using noise maskers with a bandwidth of 160 or (preferably) 320 Hz. In cases of near-normal hearing at low frequencies, we recommend using an additional LF noise to mask SDTs.

The role of attentional abilities in lexically guided perceptual learning by older listeners.

This study investigates two variables that may modify lexically guided perceptual learning: individual hearing sensitivity and attentional abilities. Older Dutch listeners (aged 60+ years, varying from good hearing to mild-to-moderate high-frequency hearing loss) were tested on a lexically guided perceptual learning task using the contrast [f]-[s]. This contrast mainly differentiates between the two consonants in the higher frequencies, and thus is supposedly challenging for listeners with hearing loss. The analyses showed that older listeners generally engage in lexically guided perceptual learning. Hearing loss and selective attention did not modify perceptual learning in our participant sample, while attention-switching control did: listeners with poorer attention-switching control showed a stronger perceptual learning effect. We postulate that listeners with better attention-switching control may, in general, rely more strongly on bottom-up acoustic information compared to listeners with poorer attention-switching control, making them in turn less susceptible to lexically guided perceptual learning. Our results, moreover, clearly show that lexically guided perceptual learning is not lost when acoustic processing is less accurate.

A Patient-Centered, Provider-Facilitated Approach to the Refinement of Nonlinear Frequency Compression Parameters Based on Subjective Preference Ratings of Amplified Sound Quality.

PURPOSE: To evaluate sound quality preferences of participants wearing hearing aids with different strengths of nonlinear frequency compression (NFC) processing versus no NFC processing. Two analysis methods, one without and one with a qualifier as to the magnitude of preferences, were compared for their percent agreement to differentiate a small difference in perceived sound quality as a result of applied NFC processing. RESEARCH DESIGN: A single-blind design was used with participants unaware of the presence or strength of NFC processing (independent variable). The National Acoustic Laboratories-Nonlinear 2 (NAL-NL2) prescription of amplification was chosen because audibility is intentionally not prescribed in the presence of larger sensorineural hearing loss thresholds. A lack of prescribed audibility, when present, was deemed an objective qualifier for NFC. NFC is known to improve the input bandwidth available to listeners when high-frequency audibility is not otherwise available and increasing strengths of NFC were examined. Experimental condition 3 (EC3) was stronger than the manufacturer default (EC2). More aggressive strengths (e.g., EC4 and EC5), however, were expected to include excessive distortion and even reduce the output bandwidth that had been prescribed as audible by NAL-NL2 (EC1). STUDY SAMPLE: A total of 14 male Veterans with severe high-frequency sensorineural hearing loss. DATA COLLECTION AND ANALYSIS: Participant sound quality preference ratings (dependent variable) without a qualifier as to the magnitude of preference were analyzed based on binomial probability theory, as is traditional with paired comparison data. The ratings with a qualifier as to the magnitude of preference were analyzed based on the nonparametric statistic of the Wilcoxon signed rank test. RESULTS: The binomial probability analysis method identified a sound quality preference as well as the nonparametric probability test method. As the strength of NFC increased, more participants preferred the EC with less NFC. Fourteen of 14 participants showed equal preference between EC1 and EC2 perhaps, in part, because EC2 showed no objective improvement in audibility for six of the 14 participants (42%). Thirteen of the 14 participants showed no preference between NAL-NL2 and EC3, but all participants had an objective improvement in audibility. With more NFC than EC3, more and more participants preferred the other EC with less NFC in the paired comparison. CONCLUSIONS: By referencing the recommended sensation levels of amplitude compression (e.g., NAL-NL2) in the ear canal of hearing aid wearers, the targeting of NFC parameters can likely be optimized with respect to improvements in effective audibility that may contribute to speech recognition without adversely impacting sound quality. After targeting of NFC parameters, providers can facilitate decisions about the use of NFC parameters (strengths of processing) via sound quality preference judgments using paired comparisons.

Effects of steep high-frequency hearing loss on speech recognition using temporal fine structure in low-frequency region.

The present study examined the effects of steep high-frequency sensorineural hearing loss (SHF-SNHL) on speech recognition using acoustic temporal fine structure (TFS) in the low-frequency region where the absolute thresholds appeared to be normal. In total, 28 participants with SHF-SNHL were assigned to 3 groups according to the cut-off frequency (1, 2, and 4 kHz, respectively) of their pure-tone absolute thresholds. Fourteen age-matched normal-hearing (NH) individuals were enrolled as controls. For each Mandarin sentence, the acoustic TFS in 10 frequency bands (each 3-ERB wide) was extracted using the Hilbert transform and was further lowpass filtered at 1, 2, and 4 kHz. Speech recognition scores were compared among the NH and 1-, 2-, and 4-kHz SHF-SNHL groups using stimuli with varying bandwidths. Results showed that speech recognition with the same TFS-speech stimulus bandwidth differed significantly in groups and filtering conditions. Sentence recognition in quiet conditions was better than that in noise. Compared with the NH participants, nearly all the SHF-SNHL participants showed significantly poorer sentence recognition within their frequency regions with "normal hearing" (defined clinically by normal absolute thresholds) in both quiet and noisy conditions. These may result from disrupted auditory nerve function in the "normal hearing" low-frequency regions.

Functional status and hearing impairments in women at midlife.

OBJECTIVES: The aim of this study was to address the prevalence of clinically assessed high-frequency hearing impairment (HFHI) and self-reported hearing impairment (SRHI) and examine the association of these hearing assessments with physical and mental functioning in African American and Caucasian women at midlife. METHODS: The sample included 467 women who participated in the Michigan Functioning Substudy of the Study of Women's Health Across the Nation. Outcomes examined were physical and mental functioning from the Medical Outcomes Trust SF-12 Health Survey. HFHI was defined as threshold averages of 25 dB or greater over 4000, 6000, and 8000 Hertz. RESULTS: Prevalence of unilateral HFHI was 26.6% (n = 68), and prevalence of bilateral HFHI was 12.0% (n = 56). Prevalence of SRHI was 16.7% (n = 78), with minimal overlap between HFHI and SRHI (n = 36). In multiple variable logistic regression analyses, HFHI in one ear only was not associated with physical or mental functioning and bilateral HFHI was associated with limited mental functioning only. SRHI was associated with limited physical and mental functioning. DISCUSSION: Poor correlation of HFHI and SRHI in this population, combined with the significant association of SRHI with both measures of functioning, indicates that the two methods may be measuring different aspects of impairment. SRHI may facilitate early identification of individuals with hearing-related functional limitations.

Speech discrimination of patients with high frequency hearing loss.

Mean speech discrimination curves were measured in three groups of patients having severe, moderate and mild high-tone hearing losses in pure-tone audiograms, 20 patients being tested in each group. The audiograms sloped linearly by 22 dB/oct. Recruiting ears in Reger's test were excluded. The group with moderate hearing loss achieved significantly poorer discrimination scores at high sound pressure levels than the group with severe hearing loss, a phenomenon not reported before. However, the results agree with preceding work in which equivalent sensorineural hearing losses were simulated with filter equipment. The causes of the phenomenon and its significance for hearing aid selection are discussed.