scholarly journals An Evaluation of Hearing Aid Beamforming Microphone Arrays in a Noisy Laboratory Setting

2019 ◽  
Vol 30 (02) ◽  
pp. 131-144 ◽  
Author(s):  
Erin M. Picou ◽  
Todd A. Ricketts
Keyword(s):  
Hearing Loss ◽  
Speech Recognition ◽  
Hearing Aids ◽  
Linear Models ◽  
Hearing Aid ◽  
Recognition Performance ◽  
Microphone Arrays ◽  
Laboratory Setting ◽  
Subjective Ratings ◽  
Sentence Recognition

AbstractPeople with hearing loss experience difficulty understanding speech in noisy environments. Beamforming microphone arrays in hearing aids can improve the signal-to-noise ratio (SNR) and thus also speech recognition and subjective ratings. Unilateral beamformer arrays, also known as directional microphones, accomplish this improvement using two microphones in one hearing aid. Bilateral beamformer arrays, which combine information across four microphones in a bilateral fitting, further improve the SNR. Early bilateral beamformers were static with fixed attenuation patterns. Recently adaptive, bilateral beamformers have been introduced in commercial hearing aids.The purpose of this article was to evaluate the potential benefits of adaptive unilateral and bilateral beamformers for improving sentence recognition and subjective ratings in a laboratory setting. A secondary purpose was to identify potential participant factors that explain some of the variability in beamformer benefit.Participants were fitted with study hearing aids equipped with commercially available adaptive unilateral and bilateral beamformers. Participants completed sentence recognition testing in background noise using three hearing aid settings (omnidirectional, unilateral beamformer, bilateral beamformer) and two noise source configurations (surround, side). After each condition, participants made subjective ratings of their perceived work, desire to control the situation, willingness to give up, and tiredness.Eighteen adults (50–80 yr, M = 66.2, σ = 8.6) with symmetrical mild sloping to severe hearing loss participated.Sentence recognition scores and subjective ratings were analyzed separately using generalized linear models with two within-subject factors (hearing aid microphone and noise configuration). Two benefit scores were calculated: (1) unilateral beamformer benefit (relative to performance with omnidirectional) and (2) additional bilateral beamformer benefit (relative to performance with unilateral beamformer). Hierarchical multiple linear regression was used to determine if beamformer benefit was associated with participant factors (age, degree of hearing loss, unaided speech in noise ability, spatial release from masking, and performance in omnidirectional).Sentence recognition and subjective ratings of work, control, and tiredness were better with both types of beamformers relative to the omnidirectional conditions. In addition, the bilateral beamformer offered small additional improvements relative to the unilateral beamformer in terms of sentence recognition and subjective ratings of tiredness. Speech recognition performance and subjective ratings were generally independent of noise configuration. Performance in the omnidirectional setting and pure-tone average were independently related to unilateral beamformer benefits. Those with the lowest performance or the largest degree of hearing loss benefited the most. No factors were significantly related to additional bilateral beamformer benefit.Adaptive bilateral beamformers offer additional advantages over adaptive unilateral beamformers in hearing aids. The small additional advantages with the adaptive beamformer are comparable to those reported in the literature with static beamformers. Although the additional benefits are small, they positively affected subjective ratings of tiredness. These data suggest that adaptive bilateral beamformers have the potential to improve listening in difficult situations for hearing aid users. In addition, patients who struggle the most without beamforming microphones may also benefit the most from the technology.

scholarly journals Degree of Hearing Loss Affects Bilateral Hearing Aid Benefits in Ecologically Relevant Laboratory Conditions

2019 ◽  
Vol 62 (10) ◽  
pp. 3834-3850 ◽  
Author(s):  
Todd A. Ricketts ◽  
Erin M. Picou ◽  
James Shehorn ◽  
Andrew B. Dittberner
Keyword(s):  
Hearing Loss ◽  
Speech Recognition ◽  
Hearing Aids ◽  
Visual Cues ◽  
Hearing Aid ◽  
Recognition Performance ◽  
Listening Effort ◽  
Sentence Recognition ◽  
Predictive Variables ◽  
The Relationship

Purpose Previous evidence supports benefits of bilateral hearing aids, relative to unilateral hearing aid use, in laboratory environments using audio-only (AO) stimuli and relatively simple tasks. The purpose of this study was to evaluate bilateral hearing aid benefits in ecologically relevant laboratory settings, with and without visual cues. In addition, we evaluated the relationship between bilateral benefit and clinically viable predictive variables. Method Participants included 32 adult listeners with hearing loss ranging from mild–moderate to severe–profound. Test conditions varied by hearing aid fitting type (unilateral, bilateral) and modality (AO, audiovisual). We tested participants in complex environments that evaluated the following domains: sentence recognition, word recognition, behavioral listening effort, gross localization, and subjective ratings of spatialization. Signal-to-noise ratio was adjusted to provide similar unilateral speech recognition performance in both modalities and across procedures. Results Significant and similar bilateral benefits were measured for both modalities on all tasks except listening effort, where bilateral benefits were not identified in either modality. Predictive variables were related to bilateral benefits in some conditions. With audiovisual stimuli, increasing hearing loss, unaided speech recognition in noise, and unaided subjective spatial ability were significantly correlated with increased benefits for many outcomes. With AO stimuli, these same predictive variables were not significantly correlated with outcomes. No predictive variables were correlated with bilateral benefits for sentence recognition in either modality. Conclusions Hearing aid users can expect significant bilateral hearing aid advantages for ecologically relevant, complex laboratory tests. Although future confirmatory work is necessary, these data indicate the presence of vision strengthens the relationship between bilateral benefits and degree of hearing loss.

Working Memory Capacity May Influence Perceived Effort during Aided Speech Recognition in Noise

2012 ◽  
Vol 23 (08) ◽  
pp. 577-589 ◽  
Author(s):  
Mary Rudner ◽  
Thomas Lunner ◽  
Thomas Behrens ◽  
Elisabet Sundewall Thorén ◽  
Jerker Rönnberg
Keyword(s):  
Working Memory ◽  
Hearing Loss ◽  
Speech Recognition ◽  
Hearing Aid ◽  
Recognition Performance ◽  
Cognitive Capacity ◽  
Subjective Ratings ◽  
Perceived Effort ◽  
Noise Type ◽  
Speech Recognition In Noise

Background: Recently there has been interest in using subjective ratings as a measure of perceived effort during speech recognition in noise. Perceived effort may be an indicator of cognitive load. Thus, subjective effort ratings during speech recognition in noise may covary both with signal-to-noise ratio (SNR) and individual cognitive capacity. Purpose: The present study investigated the relation between subjective ratings of the effort involved in listening to speech in noise, speech recognition performance, and individual working memory (WM) capacity in hearing impaired hearing aid users. Research Design: In two experiments, participants with hearing loss rated perceived effort during aided speech perception in noise. Noise type and SNR were manipulated in both experiments, and in the second experiment hearing aid compression release settings were also manipulated. Speech recognition performance was measured along with WM capacity. Study Sample: There were 46 participants in all with bilateral mild to moderate sloping hearing loss. In Experiment 1 there were 16 native Danish speakers (eight women and eight men) with a mean age of 63.5 yr (SD = 12.1) and average pure tone (PT) threshold of 47. 6 dB (SD = 9.8). In Experiment 2 there were 30 native Swedish speakers (19 women and 11 men) with a mean age of 70 yr (SD = 7.8) and average PT threshold of 45.8 dB (SD = 6.6). Data Collection and Analysis: A visual analog scale (VAS) was used for effort rating in both experiments. In Experiment 1, effort was rated at individually adapted SNRs while in Experiment 2 it was rated at fixed SNRs. Speech recognition in noise performance was measured using adaptive procedures in both experiments with Dantale II sentences in Experiment 1 and Hagerman sentences in Experiment 2. WM capacity was measured using a letter-monitoring task in Experiment 1 and the reading span task in Experiment 2. Results: In both experiments, there was a strong and significant relation between rated effort and SNR that was independent of individual WM capacity, whereas the relation between rated effort and noise type seemed to be influenced by individual WM capacity. Experiment 2 showed that hearing aid compression setting influenced rated effort. Conclusions: Subjective ratings of the effort involved in speech recognition in noise reflect SNRs, and individual cognitive capacity seems to influence relative rating of noise type.

The Effects of Changes in Head Angle on Auditory and Visual Input for Omnidirectional and Directional Microphone Hearing Aids

2003 ◽  
Vol 12 (1) ◽  
pp. 41-51 ◽  
Author(s):  
Paula Henry ◽  
Todd Ricketts
Keyword(s):  
Hearing Loss ◽  
Speech Recognition ◽  
Hearing Aids ◽  
Visual Cues ◽  
Signal To Noise Ratio ◽  
Hearing Aid ◽  
Recognition Performance ◽  
Binaural Hearing ◽  
Increase Signal Intensity ◽  
Visual Mode

Improving the signal-to-noise ratio (SNR) for individuals with hearing loss who are listening to speech in noise provides an obvious benefit. Although binaural hearing provides the greatest advantage over monaural hearing in noise, some individuals with symmetrical hearing loss choose to wear only one hearing aid. The present study tested the hypothesis that individuals with symmetrical hearing loss fit with one hearing aid would demonstrate improved speech recognition in background noise with increases in head turn. Fourteen individuals were fit monaurally with a Starkey Gemini in-the-ear (ITE) hearing aid with directional and omnidirectional microphone modes. Speech recognition performance in noise was tested using the audiovisual version of the Connected Speech Test (CST v.3). The test was administered in auditory-only conditions as well as with the addition of visual cues for each of three head angles: 0°, 20°, and 40°. Results indicated improvement in speech recognition performance with changes in head angle for the auditory-only presentation mode at the 20° and 40° head angles when compared to 0°. Improvement in speech recognition performance for the auditory + visual mode was noted for the 20° head angle when compared to 0°. Additionally, a decrement in speech recognition performance for the auditory + visual mode was noted for the 40° head angle when compared to 0°. These results support a speech recognition advantage for listeners fit with one ITE hearing aid listening in a close listener-to-speaker distance when they turn their head slightly in order to increase signal intensity.

Efficacy of Hearing-Aid Based Telephone Strategies for Listeners with Moderate-to-Severe Hearing Loss

2013 ◽  
Vol 24 (01) ◽  
pp. 059-070 ◽  
Author(s):  
Erin M. Picou ◽  
Todd A. Ricketts
Keyword(s):  
Hearing Loss ◽  
Speech Recognition ◽  
Sensorineural Hearing Loss ◽  
Hearing Aid ◽  
Recognition Performance ◽  
Sensorineural Hearing ◽  
Subjective Ratings ◽  
Severe Hearing Loss ◽  
Acoustic Coupling ◽  
Wireless Routing

Background: Understanding speech over the telephone when listening in noisy environments may present a significant challenge for listeners with moderate-to-severe hearing loss. Purpose: The purpose of this study was to compare speech recognition and subjective ratings across several hearing aid-based telephone listening strategies for individuals with moderate-to-severe sensorineural hearing loss. Research Design: Speech recognition and subjective ratings were evaluated for a simulated telephone signal. The strategies evaluated included acoustic telephone, unilateral telecoil, unilateral wireless streaming, and bilateral wireless streaming. Participants were seated in a noisy room for all evaluations. Study Sample: Eighteen adults, aged 49–88 yr, with moderate-to-severe sensorineural hearing loss participated. Data Collection and Analysis: Speech recognition scores on the Connected Speech Test were converted to rationalized arcsine units and analyzed using analysis of variance testing and Tukey post hoc analyses. Subjective ratings of ease and comfort were also analyzed in this manner. Results: Speech recognition performance was poorest with acoustic coupling to the telephone and best with bilateral wireless routing. Telecoil coupling resulted in better speech recognition performance than acoustic coupling, but was significantly poorer than bilateral wireless routing. Furthermore, unilateral wireless routing and telecoil coupling generally led to similar speech recognition performance, except in lower-level background noise conditions, for which unilateral routing resulted in better performance than the telecoil. Conclusions: For people with moderate-to-severe sensorineural hearing loss, acoustic telephone listening with a hearing aid may not lead to acceptable performance in noise. Although unilateral routing options (telecoil and wireless streaming) improved performance, speech recognition performance and subjective ratings of ease and comfort were best when bilateral wireless routing was used. These results suggest that wireless routing is a potentially beneficial telephone listening strategy for listeners with moderate-to-severe hearing loss who are fitted with limited venting if the telephone signal is routed to both ears. Unilateral wireless routing may provide similar benefits to traditional unilateral telecoil. However, the newer wireless systems may have the advantage for some listeners in that they do not include some of the positioning constraints associated with telecoil use.

An Evaluation of Several Rationales for Selecting Hearing Aid Gain

1986 ◽  
Vol 51 (3) ◽  
pp. 272-281 ◽  
Author(s):  
Larry E. Humes
Keyword(s):  
Hearing Loss ◽  
Speech Recognition ◽  
Hearing Aids ◽  
Hearing Aid ◽  
Recognition Performance ◽  
Second Phase ◽  
Selection Procedures ◽  
Relative Gain ◽  
Typical Range ◽  
Selection Of

The present study evaluates the rationales underlying several hearing aid selection procedures. The first portion of the evaluation confirms that the gain-selection rationales result in the selection of different hearing aids for a given patient. Nine different audiometric configurations representing varying degrees of fiat, sloping, and rising sensorineural hearing loss were considered. The second phase of the evaluation considered how well each procedure achieved the goal of maximizing speech recognition. This analysis made use of the Articulation Index and was applied to each of the nine audiometric configurations. The results of this analysis suggested that, given the ability to adjust the overall gain over a typical range available through most volume controls, any of the procedures could produce optimal aided speech recognition performance. The final portion of the evaluation examined the ability of each procedure to prescribe absolute gain and relative gain (frequency response) that corresponded to that preferred by hearing aid wearers. The data for preferred insertion gain came from a recent investigation by Leijon, Eriksson-Mangold, an d Beck-Karlsen (1984). The results of this evaluation suggested that some procedures prescribe gain values closer to those preferred by listeners than others. More data are needed on preferred gain values for a variety of configurations, however, before any one procedure can be recommended over another.

Effects of Reducing Low-Frequency Amplification on Consonant Perception in Quiet and Noise

1984 ◽  
Vol 27 (4) ◽  
pp. 483-493 ◽  
Author(s):  
Sandra Gordon-Salant
Keyword(s):  
Hearing Loss ◽  
Speech Recognition ◽  
Hearing Aids ◽  
High Frequency ◽  
Hearing Aid ◽  
Recognition Performance ◽  
Low Frequency ◽  
Identification Performance ◽  
Phonetic Feature ◽  
Consonant Recognition

The aim of this study was to assess the effect of low-frequency amplification on speech recognition performance by hearing-impaired listeners. Consonant identification performance by subjects with flat hearing losses and high-frequency hearing losses was assessed in three different hearing aid conditions, in quiet and noise. The experimental hearing aids all provided extra high-frequency amplification but differed in the amount of low-frequency amplification. The results showed that listeners with flat hearing losses benefited by low-frequency amplification, whereas subjects with high-frequency hearing losses exhibited deteriorating scores in conditions with greatest low-frequency amplification. Analyses of phonetic feature perception and individual consonant recognition scores revealed subtle interactions between hearing loss configuration and amplification contour.

Speech Recognition In Hearing Aids: Used For Assessing CI Candidacy In Tonal Language Population

2021 ◽  
Author(s):  
Yu-Lin Chang ◽  
Chia-Jou Liu ◽  
Pey-Yu Chen ◽  
Hung-Ching Lin
Keyword(s):  
Hearing Loss ◽  
Speech Recognition ◽  
Recognition Test ◽  
Hearing Aids ◽  
Hearing Aid ◽  
Recognition Performance ◽  
Pure Tone Audiometry ◽  
Profound Hearing Loss ◽  
Tonal Language ◽  
Severe Hearing Loss

Abstract Objective: CI (cochlear implantation) candidacy is somewhat controversial in severe hearing loss among tonal mandarin-speaking patients. To assess the relationship between pure tone audiometry (PTA) and speech recognition score (SRS), with and without hearing aid amplification, among patients who did not meet the NIH criteria of CI candidacy in tonal language mandarian-speaking countries, especially those with severe hearing loss (70 dB HL < 4FPTA(0.5, 1, 2, 4 KHz) ≤ 90 dB HL) Materials and Methods: A total of 414 patients with sensorineural hearing loss with 774 ears were reviewed retrospectively in a tertiary referral center. The Mandarin Monosyllable Recognition Test (MMRT) was used to evaluate the SRS of these ears. Results: 31% (10/32) of the 32 ears with severe hearing loss, 70-90 dB HL, still showed poor speech recognition (SRS<30%) after hearing aid amplification, while 71% (46/65) of the 65 ears with profound hearing loss, > 90 dB HL, showed poor speech recognition with hearing aid amplification. Conclusions: The speech audiometry with Mandarin Monosyllable Recognition Test (MMRT) helped identify those patients whose 4FPTA< 90 dB HL fell outside the CI candidacy criteria of NIH in tonal language mandarin-speaking countries but showed significantly poor (SRS< 30%) speech recognition performance.

scholarly journals Evaluation of a Remote Microphone System with Tri-Microphone Beamformer

2020 ◽  
Vol 31 (01) ◽  
pp. 050-060 ◽  
Author(s):  
Jace Wolfe ◽  
Mila Duke ◽  
Erin Schafer ◽  
Christine Jones ◽  
Lori Rakita ◽  
...  
Keyword(s):  
Hearing Loss ◽  
Speech Recognition ◽  
Small Group ◽  
Hearing Aids ◽  
Hearing Aid ◽  
Group Learning ◽  
Learning Activities ◽  
Small Group Learning ◽  
Sentence Recognition ◽  
Percentage Points

AbstractChildren with hearing loss often experience difficulty understanding speech in noisy and reverberant classrooms. Traditional remote microphone use, in which the teacher wears a remote microphone that captures her speech and wirelessly delivers it to radio receivers coupled to a child’s hearing aids, is often ineffective for small-group listening and learning activities. A potential solution is to place a remote microphone in the middle of the desk used for small-group learning situations to capture the speech of the peers around the desk and wirelessly deliver the speech to the child’s hearing aids.The objective of this study was to compare speech recognition of children using hearing aids across three conditions: (1) hearing aid in an omnidirectional microphone mode (HA-O), (2) hearing aid with automatic activation of a directional microphone (HA-ADM) (i.e., the hearing aid automatically switches in noisy environments from omnidirectional mode to a directional mode with a cardioid polar plot pattern), and (3) HA-ADM with simultaneous use of a remote microphone (RM) in a “Small Group” mode (HA-ADM-RM). The Small Group mode is designed to pick up multiple near-field talkers. An additional objective of this study was to compare the subjective listening preferences of children between the HA-ADM and HA-ADM-RM conditions.A single-group, repeated measures design was used to evaluate performance differences obtained in the three technology conditions. Sentence recognition in noise was assessed in a classroom setting with each technology, while sentences were presented at a fixed level from three different loudspeakers surrounding a desk (0, 90, and 270° azimuth) at which the participant was seated. This arrangement was intended to simulate a small-group classroom learning activity.Fifteen children with moderate to moderately severe hearing loss.Speech recognition was evaluated in the three hearing technology conditions, and subjective auditory preference was evaluated in the HA-ADM and HA-ADM-RM conditions.The use of the remote microphone system in the Small Group mode resulted in a statistically significant improvement in sentence recognition in noise of 24 and 21 percentage points compared with the HA-O and HA-ADM conditions, respectively (individual benefit ranged from −8.6 to 61.1 and 3.4 to 44 percentage points, respectively). There was not a significant difference in sentence recognition in noise between the HA-O and HA-ADM conditions when the remote microphone system was not in use. Eleven of the 14 participants who completed the subjective rating scale reported at least a slight preference for the use of the remote microphone system in the Small Group mode.Objective and subjective measures of sentence recognition indicated that use of remote microphone technology with the Small Group mode may improve hearing performance in small-group learning activities. Sentence recognition in noise improved by 24 percentage points compared to the HA-O condition, and children expressed a preference for the use of the remote microphone Small Group technology regarding listening comfort, sound quality, speech intelligibility, background noise reduction, and overall listening experience.

scholarly journals Unilateral hearing loss and the use of hearing aid: speech recognition, benefit, self-perception of functional performance and satisfaction

Revista CEFAC ◽  
2019 ◽  
Vol 21 (1) ◽  
Author(s):  
Lidiéli Dalla Costa ◽  
Sinéia Neujahr dos Santos ◽  
Maristela Julio Costa
Keyword(s):  
Hearing Loss ◽  
Speech Recognition ◽  
Hearing Aids ◽  
Functional Performance ◽  
Hearing Aid ◽  
Brazilian Portuguese ◽  
Unilateral Hearing Loss ◽  
Life Questionnaire ◽  
Self Perception ◽  
Sound Amplification

ABSTRACT Purpose: to investigate speech recognition in silence and in noise in subjects with unilateral hearing loss with and without hearing aids, and to analyze the benefit, self-perception of functional performance, satisfaction and the use of hearing aids in these subjects. Methods: eleven adults with unilateral, mixed and sensorineural, mild to severe hearing loss participated in this study. Speech recognition was evaluated by the Brazilian Portuguese sentences lists test; functional performance of the hearing was assessed by using the Speech Spatial and Qualities of Hearing Scale questionnaire; satisfaction was assessed by the Satisfaction with Amplification in Daily Life questionnaire, both in Brazilian Portuguese; and to assess the use of hearing aids, the patient's report was analyzed. Results: the adaptation of hearing aids provided benefits in speech recognition in all positions evaluated, both in silence and in noise. The subjects did not report major limitations in communication activities with the use of hearing aids. They were satisfied with the use of sound amplification. Most of the subjects did not use hearing aids, effectively. The discontinuity of hearing aids use can be justified by the difficulty on perceiving participation’s restriction caused by hearing loss, as well as the benefit of the hearing aid, besides the concern with batteries’ costs and aesthetic aspects. Conclusion: although showing benefits in speech recognition, in silence and in noise, and satisfaction with sound amplification, most subjects with unilateral hearing loss do not effectively use hearing aids.

Low-level Speech Recognition of Children with Hearing Aids

2021 ◽  
Author(s):  
Jace Wolfe ◽  
Mila Duke ◽  
Sharon Miller ◽  
Erin Schafer ◽  
Christine Jones ◽  
...  
Keyword(s):  
Hearing Loss ◽  
Speech Recognition ◽  
Word Recognition ◽  
Hearing Aids ◽  
Hearing Aid ◽  
Phase 1 ◽  
Second Phase ◽  
Phase 2 ◽  
Low Level ◽  
Children With Hearing Loss

Background: For children with hearing loss, the primary goal of hearing aids is to provide improved access to the auditory environment within the limits of hearing aid technology and the child’s auditory abilities. However, there are limited data examining aided speech recognition at very low (40 dBA) and low (50 dBA) presentation levels. Purpose: Due to the paucity of studies exploring aided speech recognition at low presentation levels for children with hearing loss, the present study aimed to 1) compare aided speech recognition at different presentation levels between groups of children with normal hearing and hearing loss, 2) explore the effects of aided pure tone average (PTA) and aided Speech Intelligibility Index (SII) on aided speech recognition at low presentation levels for children with hearing loss ranging in degree from mild to severe, and 3) evaluate the effect of increasing low-level gain on aided speech recognition of children with hearing loss. Research Design: In phase 1 of this study, a two-group, repeated-measures design was used to evaluate differences in speech recognition. In phase 2 of this study, a single-group, repeated-measures design was used to evaluate the potential benefit of additional low-level hearing aid gain for low-level aided speech recognition of children with hearing loss. Study Sample: The first phase of the study included 27 school-age children with mild to severe sensorineural hearing loss and 12 school-age children with normal hearing. The second phase included eight children with mild to moderate sensorineural hearing loss. Intervention: Prior to the study, children with hearing loss were fitted binaurally with digital hearing aids. Children in the second phase were fitted binaurally with digital study hearing aids and completed a trial period with two different gain settings: 1) gain required to match hearing aid output to prescriptive targets (i.e., primary program), and 2) a 6-dB increase in overall gain for low-level inputs relative to the primary program. In both phases of this study, real-ear verification measures were completed to ensure the hearing aid output matched prescriptive targets. Data Collection and Analysis: Phase 1 included monosyllabic word recognition and syllable-final plural recognition at three presentation levels (40, 50, and 60 dBA). Phase 2 compared speech recognition performance for the same test measures and presentation levels with two differing gain prescriptions. Results and Conclusions: In phase 1 of the study, aided speech recognition was significantly poorer in children with hearing loss at all presentation levels. Higher aided SII in the better ear (55 dB SPL input) was associated with higher CNC word recognition at a 40 dBA presentation level. In phase 2, increasing the hearing aid gain for low-level inputs provided a significant improvement in syllable-final plural recognition at very low-level inputs and resulted in a non-significant trend toward better monosyllabic word recognition at very low presentation levels. Additional research is needed to document the speech recognition difficulties children with hearing aids may experience with low-level speech in the real world as well as the potential benefit or detriment of providing additional low-level hearing aid gain

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