Quantification of Directional Benefit across Different Polar Response Patterns

2004 ◽  
Vol 15 (09) ◽  
pp. 649-659 ◽  
Author(s):  
Ruth A. Bentler ◽  
Jessica L.M. Egge ◽  
Jill L. Tubbs ◽  
Andrew B. Dittberner ◽  
Gregory A. Flamme
Keyword(s):  
Speech Perception ◽  
Hearing Aids ◽  
Hearing Aid ◽  
Sound Quality ◽  
Response Patterns ◽  
Directional Microphones ◽  
Speech In Noise ◽  
Directional Microphone ◽  
Hearing In Noise ◽  
The Right

The purpose of this study was to assess the relationship between the directivity of a directional microphone hearing aid and listener performance. Hearing aids were fit bilaterally to 19 subjects with sensorineural hearing loss, and five microphone conditions were assessed: omnidirectional, cardioid, hypercardioid, supercardioid, and "monofit," wherein the left hearing aid was set to omnidirectional and the right hearing aid to hypercardioid. Speech perception performance was assessed using the Hearing in Noise Test (HINT) and the Connected Speech Test (CST). Subjects also assessed eight domains of sound quality for three stimuli (speech in quiet, speech in noise, and music). A diffuse soundfield system composed of eight loudspeakers forming the corners of a cube was used to output the background noise for the speech perception tasks and the three stimuli used for sound quality judgments. Results indicated that there were no significant differences in the HINT or CST performance, or sound quality judgments, across the four directional microphone conditions when tested in a diffuse field. Of particular interest was the monofit condition: Performance on speech perception tests was the same whether one or two directional microphones were used.

The Effects of Varying Directional Bandwidth in Hearing Aid Users' Preference and Speech-in-Noise Performance

2018 ◽  
Vol 27 (1) ◽  
pp. 95-103
Author(s):  
Adriana Goyette ◽  
Jeff Crukley ◽  
Jason Galster
Keyword(s):  
Hearing Impairment ◽  
High Frequency ◽  
Hearing Aid ◽  
Internal Noise ◽  
Normal Hearing ◽  
Noise Performance ◽  
Directional Microphones ◽  
Speech In Noise ◽  
Directional Microphone ◽  
Hearing In Noise

Purpose Directional microphone systems are typically used to improve hearing aid users' understanding of speech in noise. However, directional microphones also increase internal hearing aid noise. The purpose of this study was to investigate how varying directional microphone bandwidth affected listening preference and speech-in-noise performance. Method Ten participants with normal hearing and 10 participants with hearing impairment compared internal noise levels between hearing aid memories with 4 different microphone modes: omnidirectional, full directional, high-frequency directionality with directional processing above 900 Hz, and high-frequency directionality with directional processing above 2000 Hz. Speech-in-noise performance was measured with each memory for the participants with hearing impairment. Results Participants with normal hearing preferred memories with less directional bandwidth. Participants with hearing impairment also tended to prefer the memories with less directional bandwidth. However, the majority of participants with hearing impairment did not indicate a preference between omnidirectional and directional above 2000 Hz memories. Average hearing-in-noise performance improved with increasing directional bandwidth. Conclusions Most participants preferred memories with less directional bandwidth in quiet. Participants with hearing impairment indicated no difference in preference between directional above 2000 Hz and the omnidirectional memories. Speech recognition in noise performance improved with increasing directional bandwidth.

Evaluation of a Second-Order Directional Microphone Hearing Aid: I. Speech Perception Outcomes

2006 ◽  
Vol 17 (03) ◽  
pp. 179-189 ◽  
Author(s):  
Ruth Bentler ◽  
Catherine Palmer ◽  
Gustav H. Mueller
Keyword(s):  
Speech Perception ◽  
Noise Reduction ◽  
Hearing Aids ◽  
Hearing Aid ◽  
Second Order ◽  
Directional Microphones ◽  
Noise Environment ◽  
Directional Microphone ◽  
Nonlinear Version ◽  
Omnidirectional Microphones

This clinical trial was undertaken to evaluate the benefit obtained from hearing aids employing second-order adaptive directional microphone technology, used in conjunction with digital noise reduction. Data were collected for 49 subjects across two sites. New and experienced hearing aid users were fit bilaterally with behind-the-ear hearing aids using the National Acoustics Laboratory—Nonlinear version 1 (NAL-NL1) prescriptive method with manufacturer default settings for various parameters of signal processing (e.g., noise reduction, compression, etc.). Laboratory results indicated that (1) for the stationary noise environment, directional microphones provided better speech perception than omnidirectional microphones, regardless of the number of microphones; and (2) for the moving noise environment, the three-microphone option (whether in adaptive or fixed mode) and the two-microphone option in its adaptive mode resulted in better performance than the two-microphone fixed mode, or the omnidirectional modes.

scholarly journals Speech Perception in Noise: Directional Microphones versus Frequency Modulation (FM) Systems

2004 ◽  
Vol 15 (06) ◽  
pp. 426-439 ◽  
Author(s):  
M. Samantha Lewis ◽  
Carl C. Crandell ◽  
Michael Valente ◽  
Jane Enrietto Horn
Keyword(s):  
Speech Perception ◽  
Hearing Aids ◽  
Frequency Modulation ◽  
Speech Perception In Noise ◽  
Directional Microphones ◽  
Directional Microphone ◽  
Hearing In Noise ◽  
Noise Test ◽  
Diffuse Noise ◽  
Better Than

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 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 rather than with just one FM receiver. Directional microphone performance was significantly better than omnidirectional microphone performance. All aided listening conditions were significantly better than the unaided listening condition.

scholarly journals Listener Performance with a Novel Hearing Aid Frequency Lowering Technique

2017 ◽  
Vol 28 (09) ◽  
pp. 810-822 ◽  
Author(s):  
Benjamin J. Kirby ◽  
Judy G. Kopun ◽  
Meredith Spratford ◽  
Clairissa M. Mollak ◽  
Marc A. Brennan ◽  
...  
Keyword(s):  
Signal Processing ◽  
Hearing Loss ◽  
Speech Perception ◽  
Hearing Aids ◽  
High Frequency ◽  
Hearing Aid ◽  
Sound Quality ◽  
Processing Strategy ◽  
Listening Effort ◽  
At Home

AbstractSloping hearing loss imposes limits on audibility for high-frequency sounds in many hearing aid users. Signal processing algorithms that shift high-frequency sounds to lower frequencies have been introduced in hearing aids to address this challenge by improving audibility of high-frequency sounds.This study examined speech perception performance, listening effort, and subjective sound quality ratings with conventional hearing aid processing and a new frequency-lowering signal processing strategy called frequency composition (FC) in adults and children.Participants wore the study hearing aids in two signal processing conditions (conventional processing versus FC) at an initial laboratory visit and subsequently at home during two approximately six-week long trials, with the order of conditions counterbalanced across individuals in a double-blind paradigm.Children (N = 12, 7 females, mean age in years = 12.0, SD = 3.0) and adults (N = 12, 6 females, mean age in years = 56.2, SD = 17.6) with bilateral sensorineural hearing loss who were full-time hearing aid users.Individual performance with each type of processing was assessed using speech perception tasks, a measure of listening effort, and subjective sound quality surveys at an initial visit. At the conclusion of each subsequent at-home trial, participants were retested in the laboratory. Linear mixed effects analyses were completed for each outcome measure with signal processing condition, age group, visit (prehome versus posthome trial), and measures of aided audibility as predictors.Overall, there were few significant differences in speech perception, listening effort, or subjective sound quality between FC and conventional processing, effects of listener age, or longitudinal changes in performance. Listeners preferred FC to conventional processing on one of six subjective sound quality metrics. Better speech perception performance was consistently related to higher aided audibility.These results indicate that when high-frequency speech sounds are made audible with conventional processing, speech recognition ability and listening effort are similar between conventional processing and FC. Despite the lack of benefit to speech perception, some listeners still preferred FC, suggesting that qualitative measures should be considered when evaluating candidacy for this signal processing strategy.

Low-Frequency Gain Compensation in Directional Hearing Aids

2002 ◽  
Vol 11 (1) ◽  
pp. 29-41 ◽  
Author(s):  
Todd Ricketts ◽  
Paula Henry
Keyword(s):  
Hearing Loss ◽  
Hearing Aids ◽  
Low Frequency ◽  
Sound Quality ◽  
Directional Hearing ◽  
Low Frequencies ◽  
Speech In Noise ◽  
Directional Microphone ◽  
Listening Environments ◽  
Gain Compensation

Hearing aids currently available on the market with both omnidirectional and directional microphone modes often have reduced amplification in the low frequencies when in directional microphone mode due to better phase matching. The effects of this low-frequency gain reduction for individuals with hearing loss in the low frequencies was of primary interest. Changes in sound quality for quiet listening environments following gain compensation in the low frequencies was of secondary interest. Thirty participants were fit with bilateral in-the-ear hearing aids, which were programmed in three ways while in directional microphone mode: no-gain compensation, adaptive-gain compensation, and full-gain compensation. All participants were tested with speech in noise tasks. Participants also made sound quality judgments based on monaural recordings made from the hearing aid. Results support a need for gain compensation for individuals with low-frequency hearing loss of greater than 40 dB HL.

Fitting Noise Management Signal Processing Applying the American Academy of Audiology Pediatric Amplification Guideline: Verification Protocols

2016 ◽  
Vol 27 (03) ◽  
pp. 237-251 ◽  
Author(s):  
Susan Scollie ◽  
Charla Levy ◽  
Nazanin Pourmand ◽  
Parvaneh Abbasalipour ◽  
Marlene Bagatto ◽  
...  
Keyword(s):  
Hearing Loss ◽  
Clinical Practice ◽  
Noise Reduction ◽  
Hearing Aids ◽  
Hearing Aid ◽  
Sound Quality ◽  
Speech In Noise ◽  
Verification Systems ◽  
Clinical Verification ◽  
Noise Management

Background: Although guidelines for fitting hearing aids for children are well developed and have strong basis in evidence, specific protocols for fitting and verifying some technologies are not always available. One such technology is noise management in children’s hearing aids. Children are frequently in high-level and/or noisy environments, and many options for noise management exist in modern hearing aids. Verification protocols are needed to define specific test signals and levels for use in clinical practice. Purpose: This work aims to (1) describe the variation in different brands of noise reduction processors in hearing aids and the verification of these processors and (2) determine whether these differences are perceived by 13 children who have hearing loss. Finally, we aimed to develop a verification protocol for use in pediatric clinical practice. Study Sample: A set of hearing aids was tested using both clinically available test systems and a reference system, so that the impacts of noise reduction signal processing in hearing aids could be characterized for speech in a variety of background noises. A second set of hearing aids was tested across a range of audiograms and across two clinical verification systems to characterize the variance in clinical verification measurements. Finally, a set of hearing aid recordings that varied by type of noise reduction was rated for sound quality by children with hearing loss. Results: Significant variation across makes and models of hearing aids was observed in both the speed of noise reduction activation and the magnitude of noise reduction. Reference measures indicate that noise-only testing may overestimate noise reduction magnitude compared to speech-in-noise testing. Variation across clinical test signals was also observed, indicating that some test signals may be more successful than others for characterization of hearing aid noise reduction. Children provided different sound quality ratings across hearing aids, and for one hearing aid rated the sound quality as higher with the noise reduction system activated. Conclusions: Implications for clinical verification systems may be that greater standardization and the use of speech-in-noise test signals may improve the quality and consistency of noise reduction verification cross clinics. A suggested clinical protocol for verification of noise management in children’s hearing aids is suggested.

Performance of Directional Microphones for Hearing Aids: Real-World versus Simulation

2004 ◽  
Vol 15 (06) ◽  
pp. 440-455 ◽  
Author(s):  
Cynthia L. Compton-Conley ◽  
Arlene C. Neuman ◽  
Mead C. Killion ◽  
Harry Levitt
Keyword(s):  
Hearing Aids ◽  
Real World ◽  
Noise Source ◽  
Live Performance ◽  
Space Condition ◽  
Directional Microphones ◽  
Directional Microphone ◽  
Simulation Techniques ◽  
Hearing In Noise ◽  
The Absolute

The purpose of this study was to assess the accuracy of clinical and laboratory measures of directional microphone benefit. Three methods of simulating a noisy restaurant listening situation ([1] a multimicrophone/multiloudspeaker simulation, the R-SPACE™, [2] a single noise source behind the listener, and [3] a single noise source above the listener) were evaluated and compared to the "live" condition. Performance with three directional microphone systems differing in polar pattern (omnidirectional, supercardioid, and hypercardioid array) and directivity indices (0.34, 4.20, and 7.71) was assessed using a modified version of the Hearing in Noise Test (HINT). The evaluation revealed that the three microphones could be ordered with regard to the benefit obtained using any of the simulation techniques. However, the absolute performance obtained with each microphone type differed among simulations. Only the R-SPACE simulation yielded accurate estimates of the absolute performance of all three microphones in the live condition. Performance in the R-SPACE condition was not significantly different from performance in the "live restaurant" condition. Neither of the single noise source simulations provided accurate predictions of real-world (live) performance for all three microphones.

scholarly journals Psychometric Comparison of the Hearing in Noise Test and the American English Matrix Test

2019 ◽  
Vol 30 (04) ◽  
pp. 315-326 ◽  
Author(s):  
Jumana Harianawala ◽  
Jason Galster ◽  
Benjamin Hornsby
Keyword(s):  
Speech Recognition ◽  
Hearing Aids ◽  
Repeated Measures ◽  
American English ◽  
Hearing Aid ◽  
Speech Corpus ◽  
Speech In Noise ◽  
Hearing In Noise ◽  
Noise Test ◽  
Intensity Functions

AbstractThe hearing in noise test (HINT) is the most popular adaptive test used to evaluate speech in noise performance, especially in context of hearing aid features. However, the number of conditions that can be tested on the HINT is limited by a small speech corpus. The American English Matrix test (AEMT) is a new alternative adaptive speech in noise test with a larger speech corpus. The study examined the relationships between the performance of hearing aid wearers on the HINT and the AEMT.To examine whether there was a difference in performance of hearing aid wearers on the HINT and the AEMT. A secondary purpose, given the AEMT’s steep performance-intensity function, was to determine whether the AEMT is more sensitive to changes in speech recognition resulting from directional (DIR) microphone processing in hearing aids.A repeated measures design was used in this study. Multiple measurements were made on each subject. Each measurement involved a different experimental condition.Ten adults with hearing loss participated in this study.All participants completed the AEMT and HINT, using adaptive and fixed test formats while wearing hearing aids. Speech recognition was assessed in two hearing aid microphone settings—omnidirectional and fixed DIR. All testing was conducted via sound field presentation. Performance on HINT and AEMT were systematically compared across all test conditions using a linear model with repeated measures.The results of this study revealed that adult hearing aid users perform differently on the HINT and AEMT, with adaptive AEMT testing yielding significantly better (more negative) thresholds than the HINT. Slopes of performance intensity functions obtained by testing at multiple fixed signal-to-noise ratios, revealed a somewhat steeper slope for the HINT compared with the AEMT. Despite this steeper slope, the benefit provided by DIR microphones was not significantly different between the two speech tests.The observation of similar DIR benefits of the HINT and AEMT suggests that the HINT and AEMT are equally sensitive to changes in speech recognition thresholds following intervention. Therefore, the decision to use the AEMT or the HINT will depend on the purpose of the study and/or the technology being investigated. Other test related factors such as available sentence corpus, learning effects and test time will also influence test selection.

scholarly journals Effects of Wireless Remote Microphone on Speech Recognition in Noise for Hearing Aid Users in China

2021 ◽  
Vol 15 ◽  
Author(s):  
Jing Chen ◽  
Zhe Wang ◽  
Ruijuan Dong ◽  
Xinxing Fu ◽  
Yuan Wang ◽  
...  
Keyword(s):  
Speech Recognition ◽  
Hearing Aids ◽  
Signal To Noise Ratio ◽  
Hearing Aid ◽  
Recognition Performance ◽  
Speech In Noise ◽  
Hearing In Noise ◽  
Recognition Ability ◽  
Noise Test ◽  
Test Distance

Objective: This study was aimed at evaluating improvements in speech-in-noise recognition ability as measured by signal-to-noise ratio (SNR) with the use of wireless remote microphone technology. These microphones transmit digital signals via radio frequency directly to hearing aids and may be a valuable assistive listening device for the hearing-impaired population of Mandarin speakers in China.Methods: Twenty-three adults (aged 19–80 years old) and fourteen children (aged 8–17 years old) with bilateral sensorineural hearing loss were recruited. The Mandarin Hearing in Noise Test was used to test speech recognition ability in adult subjects, and the Mandarin Hearing in Noise Test for Children was used for children. The subjects’ perceived SNR was measured using sentence recognition ability at three different listening distances of 1.5, 3, and 6 m. At each distance, SNR was obtained under three device settings: hearing aid microphone alone, wireless remote microphone alone, and hearing aid microphone and wireless remote microphone simultaneously.Results: At each test distance, for both adult and pediatric groups, speech-in-noise recognition thresholds were significantly lower with the use of the wireless remote microphone in comparison with the hearing aid microphones alone (P < 0.05), indicating better SNR performance with the wireless remote microphone. Moreover, when the wireless remote microphone was used, test distance had no effect on speech-in-noise recognition for either adults or children.Conclusion: Wireless remote microphone technology can significantly improve speech recognition performance in challenging listening environments for Mandarin speaking hearing aid users in China.

Effect of Signal-to-Noise Ratio on Directional Microphone Benefit and Preference

2005 ◽  
Vol 16 (09) ◽  
pp. 662-676 ◽  
Author(s):  
Brian E. Walden ◽  
Rauna K. Surr ◽  
Kenneth W. Grant ◽  
W. Van Summers ◽  
Mary T. Cord ◽  
...  
Keyword(s):  
Hearing Aids ◽  
Speech Intelligibility ◽  
Signal To Noise Ratio ◽  
Hearing Aid ◽  
Directional Hearing ◽  
Signal To Noise ◽  
Directional Microphones ◽  
Directional Microphone ◽  
The Individual ◽  
Directional Hearing Aids

This study examined speech intelligibility and preferences for omnidirectional and directional microphone hearing aid processing across a range of signal-to-noise ratios (SNRs). A primary motivation for the study was to determine whether SNR might be used to represent distance between talker and listener in automatic directionality algorithms based on scene analysis. Participants were current hearing aid users who either had experience with omnidirectional microphone hearing aids only or with manually switchable omnidirectional/directional hearing aids. Using IEEE/Harvard sentences from a front loudspeaker and speech-shaped noise from three loudspeakers located behind and to the sides of the listener, the directional advantage (DA) was obtained at 11 SNRs ranging from -15 dB to +15 dB in 3 dB steps. Preferences for the two microphone modes at each of the 11 SNRs were also obtained using concatenated IEEE sentences presented in the speech-shaped noise. Results revealed that a DA was observed across a broad range of SNRs, although directional processing provided the greatest benefit within a narrower range of SNRs. Mean data suggested that microphone preferences were determined largely by the DA, such that the greater the benefit to speech intelligibility provided by the directional microphones, the more likely the listeners were to prefer that processing mode. However, inspection of the individual data revealed that highly predictive relationships did not exist for most individual participants. Few preferences for omnidirectional processing were observed. Overall, the results did not support the use of SNR to estimate the effects of distance between talker and listener in automatic directionality algorithms.

Sign in / Sign up

Export Citation Format

Share Document