Experienced Hearing Aid Wearers Research Articles

Hearing at the Mall: Multibeam Processing Technology Improves Hearing Group Conversations in a Real-World Food Court Environment.

This study aimed to evaluate conversation hearing with an adaptive beamforming hearing aid that supports adaptive tracking of multiple talkers in an ecologically valid, real-world food court environment in a busy mall. Twenty older adult experienced hearing aid wearers with sensorineural hearing loss were fitted in the lab with binaural receiver-in-the-canal style hearing aids set with two programs, each having a different beamforming strategy. The participant and two researchers then met in a moderately noisy and reverberant food court at a local mall where the participant was asked to listen to a conversation between the two researchers. Participants rated the extent of their agreement with 10 positively worded statements specific to the conversation twice, once for each program. Participants then provided program-preference ratings for seven different aspects of a conversation during which the programs were switched back and forth by the researcher, so that participants were unaware of the condition to which they were listening. Real-world subjective ratings for all domains resulted in positive values on average for both programs. Pairwise comparisons indicated that the intervention algorithm had higher absolute ratings on five of the 10 criteria including understanding, clarity, focus, listening effort, and background noise. Ratings for preference between programs indicated a significant preference for the intervention algorithm for all seven criteria. In a real-world setting, the use of hearing aids with separate processing of sounds from the front and back hemisphere provided positive subjective ratings. However, following a group conversation with multiple conversation partners, improvements in the algorithm to account for the locations of interlocutors and the natural head turning of the hearing aid wearer that occurs during a conversation by adding and controlling multiple adaptive beams in the front hemisphere significantly influenced preference for all aspects rated.

Reasons for ceiling ratings in real-life evaluations of hearing aids: the relationship between SNR and hearing aid ratings.

In past Ecological Momentary Assessment (EMA) studies, hearing aid outcome ratings have often been close to ceiling. To analyze the underlying reasons for the very positive ratings, we conducted a study with 17 experienced hearing aid wearers who were fitted with study hearing aids. The acceptable noise level and the noise level where participants were unable to follow speech were measured. The participants then rated hearing aid satisfaction, speech understanding and listening effort for pre-defined SNRs between -10 and +20 dB SPL in the laboratory. These ratings were compared to ratings of a two-week EMA trial. Additionally, estimates of SNRs were collected from hearing aids during the EMA trial and we assessed whether the participants experienced those SNRs rated poorly in the laboratory in real life. The results showed that for hearing aid satisfaction and speech understanding, the full rating scale was used in the laboratory, while the ratings in real life were strongly skewed towards the positive end of the scale. In the laboratory, SNRs where participants indicated they could not follow the narrator ("unable to follow" noise level) were rated clearly better than the lowest possible ratings. This indicates that very negative ratings may not be applicable in real-life testing. The lower part of the distribution of real-life SNR estimates was related to participants' individual "unable to follow" noise levels and the SNRs which were rated poorly in the laboratory made up less than 10% of the speech situations experienced in real life. This indicates that people do not seem to frequently experience listening situations at SNRs where they are dissatisfied with their hearing aids and this could be the reason for the overly positive hearing aid outcome ratings in EMA studies. It remains unclear to what extent the scarcity of such situations is due lack of encounters or intentional avoidance.

Tracking of Noise Tolerance to Predict Hearing Aid Satisfaction in Loud Noisy Environments.

A method that tracked tolerable noise level (TNL) over time while maintaining subjective speech intelligibility was reported previously. Although this method was reliable and efficacious as a research tool, its clinical efficacy and predictive ability of real-life hearing aid satisfaction were not measured. The study evaluated an adaptive method to estimate TNL using slope and variance of tracked noise level as criteria in a clinical setting. The relationship between TNL and subjective hearing aid satisfaction in noisy environments was also investigated. A single-blinded, repeated-measures design. Seventeen experienced hearing aid wearers with bilateral mild-to-moderately-severe sensorineural hearing loss. Participants listened to 82-dB SPL continuous speech and tracked the background noise level that they could "put up with" while subjectively understanding >90% of the speech material. Two trials with each babble noise and continuous speech-shaped noise were measured in a single session. All four trials were completed aided using the participants' own hearing aids. The stimuli were presented in the sound field with speech from 0° and noise from the 180° azimuth. The instantaneous tolerable noise level was measured using a custom program and scored in two ways; the averaged TNL (aTNL) over the 2-min trial and the estimated TNL (eTNL) as soon as the listeners reached a stable noise estimate. Correlation between TNL and proportion of satisfied noisy environments was examined using the MarkeTrak questionnaire. All listeners completed the tracking of noise tolerance procedure within 2 min with good reliability. Sixty-five percent of the listeners yielded a stable noise estimate after 59.9 sec of actual test time. The eTNL for all trials was 78.6 dB SPL (standard deviation [SD] = 4.4 dB). The aTNL for all trials was 78.0 dB SPL (SD = 3.3 dB) after 120 sec. The aTNL was 79.2 dB SPL (SD = 5.4 dB) for babble noise and 77.0 dB SPL (SD = 5.9 dB) for speech-shaped noise. High within-session test-retest reliability was evident. The 95% confidence interval was 1.5 dB for babble noise and 2.8 dB for continuous speech-shaped noise. No significant correlation was measured between overall hearing aid satisfaction and the aTNL (ρ = 0.20 for both noises); however, a significant relationship between aTNL and proportion of satisfied noisy situations was evident (ρ = 0.48 for babble noise and ρ = 0.55 for speech-shaped noise). The eTNL scoring method yielded similar results as the aTNL method although requiring only half the time for 65% of the listeners. This time efficiency, along with its reliability and the potential relationship between TNL and hearing aid satisfaction in noisy listening situations suggests that this procedure may be a good clinical tool to evaluate whether specific features on a hearing aid would improve noise tolerance and predict wearer satisfaction with the selected hearing aid in real-life loud noisy situations. A larger sample of hearing aid wearers is needed to further validate these potential uses.

Feasibility of Using a Smartphone-Based Hearing Aid Application to Improve Attitudes Toward Amplification and Hearing Impairment.

Objective The objective of the study was to determine whether short-term experience (i.e., 4 weeks) with a smartphone-based hearing aid application (SHAA) might positively improve attitudes toward amplification uptake and hearing impairment. Method We recruited 15 experienced hearing aid wearers who had ceased wearing their devices for > 1 year (i.e., "In-the-Drawer" group) and 15 individuals with self-reported hearing difficulties who had yet to adopt hearing aids (i.e., "First-Time" group). We obtained participant attitudes pre- and post-SHAA using 3 surveys and analyzed perceptible changes in attitude for each survey. Comparative findings were then generalized to the health belief model in the context of perceived benefits (i.e., efficacy of an action to reduce risk) and reduced perceived barriers (i.e., tangible and psychological costs that inhibit compliance and adoption). Results A short trial period with an SHAA appears to modify the psychological perception toward amplification and reduce listener perception with respect to hearing difficulties in both groups. Conclusion A short trial period with an SHAA improved the perceived benefits and reduced the perceived barriers in the average First-Time listener, who often delays adoption of traditional amplification. The same trial period was also found to improve perceived benefits and reduce perceived barriers for the average In-the-Drawer listener, but to a lesser degree than their First-Time counterparts.

Effect of talker variability on hearing aid benefit with closed word recognition test

The relationship between hearing aid benefit measured in a clinical setting and hearing aid performance in daily listening situations is not clearly established. A significant aspect of realistic listening situations is the variety of talkers that people normally encounter. This is a daily listening obstacle that is not easily recreated in a clinical setting; however, with the appropriate speech testing material the results could contribute to a better understanding of the benefit of amplification in realistic listening situations. Our present study investigated the interaction between talker variability and amplification benefit. Nine experienced hearing aid wearers with moderate to severe hearing loss were tested in aided and unaided conditions with the original and a multi-talker version of the WAKO word recognition test. Word recognition scores and response times were simultaneously measured for each test condition and test version. Variability of the test material was quantified in terms of the fundamental frequency and duration of each test word. The statistical analysis used a logistic mixed effect regression model on the word recognition scores and a linear mixed effect regression model on the response times. Introducing talker variability in the test material led to a significant decrease in amplification benefit for word recognition accuracy. These results suggest that using speech materials closer to that experienced in daily life might change the magnitude of measured benefit from hearing aids amplification.

Tracking of Noise Tolerance to Measure Hearing Aid Benefit.

The benefits offered by noise reduction (NR) features on a hearing aid had been studied traditionally using test conditions that set the hearing aids into a stable state of performance. While adequate, this approach does not allow the differentiation of two NR algorithms that differ in their timing characteristics (i.e., activation and stabilization time). The current study investigated a new method of measuring noise tolerance (Tracking of Noise Tolerance [TNT]) as a means to differentiate hearing aid technologies. The study determined the within-session and between-session reliability of the procedure. The benefits provided by various hearing aid conditions (aided, two NR algorithms, and a directional microphone algorithm) were measured using this procedure. Performance on normal-hearing listeners was also measured for referencing. A single-blinded, repeated-measures design was used. Thirteen experienced hearing aid wearers with a bilaterally symmetrical (≤10 dB) mild-to-moderate sensorineural hearing loss participated in the study. In addition, seven normal-hearing listeners were tested in the unaided condition. Participants tracked the noise level that met the criterion of tolerable noise level (TNL) in the presence of an 85 dB SPL continuous discourse passage. The test conditions included an unaided condition and an aided condition with combinations of NR and microphone modes within the UNIQUE hearing aid (omnidirectional microphone, no NR; omnidirectional microphone, NR; directional microphone, no NR; and directional microphone, NR) and the DREAM hearing aid (omnidirectional microphone, no NR; omnidirectional microphone, NR). Each tracking trial lasted 2 min for each hearing aid condition. Normal-hearing listeners tracked in the unaided condition only. Nine of the 13 hearing-impaired listeners returned after 3 mo for retesting in the unaided and aided conditions with the UNIQUE hearing aid. The individual TNL was estimated for each participant for all test conditions. The TNT index was calculated as the difference between 85 dB SPL and the TNL. The TNT index varied from 2.2 dB in the omnidirectional microphone, no NR condition to -4.4 dB in the directional microphone, NR on condition. Normal-hearing listeners reported a TNT index of -5.7 dB using this procedure. The averaged improvement in TNT offered by the NR algorithm on the UNIQUE varied from 2.1 dB when used with a directional microphone to 3.0 dB when used with the omnidirectional microphone. The time course of the NR algorithm was different between the UNIQUE and the DREAM hearing aids, with the UNIQUE reaching a stable TNL sooner than the DREAM. The averaged improvement in TNT index from the UNIQUE directional microphone was 3.6 dB when NR was activated and 4.4 dB when NR was deactivated. Together, directional microphone and NR resulted in a total TNT improvement of 6.5 dB. The test-retest reliability of the procedure was high, with an intrasession 95% confidence interval (CI) of 2.2 dB and an intersession 95% CI of 4.2 dB. The effect of the NR and directional microphone algorithms was measured to be 2-3 and 3.6-4.4 dB, respectively, using the TNT procedure. Because of its tracking property and reliability, this procedure may hold promise in differentiating among some hearing aid features that also differ in their time course of action.

Evaluation of a Wind Noise Attenuation Algorithm on Subjective Annoyance and Speech-in-Wind Performance.

Wind noise is a common problem reported by hearing aid wearers. The MarkeTrak VIII reported that 42% of hearing aid wearers are not satisfied with the performance of their hearing aids in situations where wind is present. The current study investigated the effect of a new wind noise attenuation (WNA) algorithm on subjective annoyance and speech recognition in the presence of wind. A single-blinded, repeated measures design was used. Fifteen experienced hearing aid wearers with bilaterally symmetrical (≤10 dB) mild-to-moderate sensorineural hearing loss participated in the study. Subjective rating for wind noise annoyance was measured for wind presented alone from 0° and 290° at wind speeds of 4, 5, 6, 7, and 10 m/sec. Phoneme identification performance was measured using Widex Office of Clinical Amplification Nonsense Syllable Test presented at 60, 65, 70, and 75 dB SPL from 270° in the presence of wind originating from 0° at a speed of 5 m/sec. The subjective annoyance from wind noise was reduced for wind originating from 0° at wind speeds from 4 to 7 m/sec. The largest improvement in phoneme identification with the WNA algorithm was 48.2% when speech was presented from 270° at 65 dB SPL and the wind originated from 0° azimuth at 5 m/sec. The WNA algorithm used in this study reduced subjective annoyance for wind speeds ranging from 4 to 7 m/sec. The algorithm was effective in improving speech identification in the presence of wind originating from 0° at 5 m/sec. These results suggest that the WNA algorithm used in the current study could expand the range of real-life situations where a hearing-impaired person can use the hearing aid optimally.

Initial-Fit Approach Versus Verified Prescription: Comparing Self-Perceived Hearing Aid Benefit

Despite evidence suggesting inaccuracy in the default fittings provided by hearing aid manufacturers, the use of probe-microphone measures for the verification of fitting accuracy is routinely used by fewer than half of practicing audiologists. The present study examined whether self-perception of hearing aid benefit, as measured through the Abbreviated Profile of Hearing Aid Benefit (APHAB; Cox and Alexander, 1995), differed as a function of hearing aid fitting method, specifically, manufacturer's initial-fit approach versus a verified prescription. The prescriptive fit began at NAL-NL1 targets, with adjustments based on participant request. Each of the two fittings included probe-microphone measurement. A counterbalanced, cross-over, repeated-measures, single-blinded design was utilized to address the research objectives. Twenty-two experienced hearing aid users from the general Bay Pines VA Healthcare System audiology clinic population were randomized into one of two intervention groups. At the first visit, half of the participants were fit with new hearing aids via the manufacturer's initial fit while the second half were fit to a verified prescription using probe-microphone measurement. After a wear period of 4-6 wk, the participants' hearing aids were refit via the alternate method and worn for an additional 4-6 wk. Participants were blinded to the method of fitting by utilizing probe-microphone measures with both approaches. The APHAB was administered at baseline and at the end of each intervention trial. At the end of the second trial period, the participants were asked to identify which hearing aid fitting was "preferred." The APHAB data were subjected to a general linear model repeated-measures analysis of variance. For the three APHAB communication subscales (i.e., Ease of Communication, Reverberation, and Background Noise) mean scores obtained with the verified prescription were higher than those obtained with the initial-fit approach, indicating greater benefit with the former. The main effect of hearing aid fitting method was statistically significant [F (1, 21) = 4.69, p = 0.042] and accounted for 18% of the variance in the data (partial eta squared = 0.183). Although the mean benefit score for the APHAB Aversiveness subscale was also better (i.e., lower) for the verified prescription than the initial-fit approach, the difference was not statistically significant. Of the 22 participants, 7 preferred their hearing aids programmed to initial-fit settings and 15 preferred their hearing aids programmed to the verified prescription. The data support the conclusion that hearing aids fit to experienced hearing aid wearers using a verified prescription are more likely to yield better self-perceived benefit as measured by the APHAB than if fit using the manufacturer's initial-fit approach.

Comparison of three procedures for initial fitting of compression hearing aids. II. Experienced users, fitted unilaterally

This paper is the second in a series comparing three procedures for the initial fitting of multichannel compression hearing aids. The first paper reported the results for a group of 10 experienced hearing aid users fitted bilaterally. This paper reports the results for a different group of 10 experienced hearing aid users fitted unilaterally. The three procedures were: (1) CAMEQ, which aims to amplify speech so as to give equal loudness per critical band over the frequency range 500-5000 Hz, and to give similar overall loudness to normal over a wide range of speech levels; (2) CAMREST, which aims to amplify speech so as to restore normal specific loudness patterns, over a wide range of speech levels; and (3) DSL [i/o], which aims to map the dynamic range of normalhearing people into the reduced dynamic range of hearingimpaired people, with full restoration of audibility. Each subject was fitted with one Danalogic 163D digital hearing aid, using each of the three fitting procedures in turn; the order was counter-balanced across subjects. Prescribed insertion gains for 55 and 80 dB SPL input levels were verified using real-ear measurements. Immediately after fitting with a given procedure, and 1 week after fitting, the gains were adjusted, when required, by the minimum amount necessary to achieve acceptable fittings. On average, the adjustments were smallest for the CAMREST procedure, slightly larger for the CAMEQ procedure, and largest of all for DSL [i/o]. For the DSL [i/o] the gain changes were mostly negative, especially for high frequencies and the higher input level. After these gain adjustments, users wore the aids for at least 3 weeks before speech reception thresholds (SRTs) for sentences in quiet and in steady and fluctuating background noise were measured. The APHAB questionnaire was also administered. The hearing aids were then refitted with the next procedure. SRTs and APHAB scores did not differ significantly between the three procedures. We conclude that the CAMEQ and CAMREST procedures provide a more appropriate initial fitting than DSL [i/o] for unilaterally experienced hearing aid wearers. Comparison with our earlier study based on bilateral fittings suggests that the preferred gains are similar for unilateral and bilateral fittings.

Evaluation of the noise reduction system in a commercial digital hearing aid: Evaluación del sistema de reducción de ruido en un auxiliar auditivo digital comercial

We evaluated the effectiveness of a noise reduction system implemented in a commercial digital multichannel compression hearing aid. Eight experienced hearing aid wearers with moderate sensorineural hearing loss were fitted bilaterally according to the manufacturer's fitting guidelines. After a 3-month period of regular use of two programs, one with and one without the noise reduction system, speech recognition thresholds (SRTs) were measured in four types of background noise, including steady noise, and noises with spectral and/or temporal dips. SRTs were very similar with and without the noise reduction system; in both cases, SRTs were markedly lower than for unaided listening. SRTs were lower for the noises with dips than for the steady noise, especially for the aided conditions, indicating that amplification can help to 'listen in the dips'. Ratings of sound quality and listening comfort in the aided conditions were uniformly high and very similar with and without the noise reduction system.Sumario: Evaluamos la efectividad del sistema de reducción de ruido en un auxiliar auditivo digital comercial con compresión multicanal. Se adaptaron auxi-liares auditivos bilateralmente a ocho usuarios experimentados con hipoacusias sensorineurales moderadas de acuerdo con las guias de adaptación del fabricante. Después de un periodo de 3 meses de uso regular de dos programas, uno con y uno sin el sistema de reducción de ruido, se midieron los umbrales de reconocimiento del lenguaje (SRT) con cuatro tipos de ruido de fondo, incluyendo ruido estacionario y ruidos con componentes espectrales y/o temporales. Los SRT fueron muy similares con y sin el sistema de reducción de ruido. En ambos casos, los SRT fueron marca-damente más bajos que en condiciones de escucha sin el auxiliar. Los SRT fueron más bajos con los ruidos que tenian componentes, en comparación con el ruido estacionario, especialmente en condiciones de uso del auxiliar, lo que indicó que la amplificación puede ayudar a escuchar en presencia de esos componentes. Los resultados en cuanto a calidad de sonido y de audición agradablc en condiciones de uso del auxiliar auditivo, fueron uniformemente elevados y muy similares con y sin el sistema de reducción de ruido.

Using conjoint analysis to examine the importance of hearing aid attributes.

To introduce conjoint analysis (CA) as a method to explain choice decisions of hearing aid users and to measure the contributions of different hearing aid attributes involved. The study was conducted using CA, a method that is well established in marketing, but has not been used for hearing aid research. CA examines the contributions (importance) various attributes make to overall preference judgements. It is based on the premises that objects (i.e., hearing aids) can be described as different combinations of several attributes. The relative importance of the attributes is estimated from integral judgements of hypothetical hearing aids. The advantages of CA are a more realistic presentation of complete products instead of isolated attributes and the consideration of trade-offs between the features. The following attributes selected from 12 features in a prestudy were included in the application: speech perception in quiet, speech perception in noise, handling, sound quality, localization, and feedback. 93 randomly chosen experienced hearing aid wearers participated in the survey. It was found that the attributes concerning speech perception were by far most important. Speech discrimination in quiet and in noise were almost equally significant and contributed with 56% to the preference decisions of the subjects. The remaining attributes showed values in the range of 10% to 12%. When comparing various subgroups dependent on age, sex, hearing loss, satisfaction, etc., significant differences concerning the preferences were found. Elder and female subjects attached greater importance of the attribute "handling" whereas younger patients judged "speech in noise" more important. In general, subjects with greater hearing loss considered speech intelligibility in quiet to be more important than in noisy surroundings. Moreover, sound quality seems to be a significant indicator for satisfaction with the hearing aid. This study proposes CA as a survey technique to examine individual preferences for hearing aids. Several assumptions about the importance of hearing aid features for different groups of users could be confirmed quantitatively. Segmentation showed valid results depending on socio-demographic and user-specific parameters. The method used and the results are of interest for audiologists as well as the hearing aid industry. They provide valuable tools for future hearing aid design and should be considered in the development of self-assessment inventories.