Acceptance of noise with monaural and binaural amplification

The present study investigated the effects of monaural and binaural amplification on speech understanding in noise and acceptance of noise for 39 listeners with hearing impairment. Results demonstrated that speech understanding in noise improved with binaural amplification; however, acceptance of noise was not dependent on monaural or binaural amplification for most listeners. These results suggest that although two hearing aids maximize speech understanding ability in noise, most individuals' acceptance of noise, which is directly related to hearing aid use, may not be affected by the use of binaural amplification. It should be noted that monaural amplification resulted in greater acceptance of noise for some listeners, indicating that binaural amplification may negatively affect some individuals' willingness to wear hearing aids. It should also be noted that interaural differences in acceptance of noise might exist for some listeners; therefore, if only one hearing aid is fitted, monaural ANLs should be measured.     

Acceptable noise level as a predictor of hearing aid use

Acceptable noise level (ANL) measures a listener's reaction to background noise while listening to speech. Relations among hearing aid use and ANL, speech in noise (SPIN) scores, and listener characteristics (age, gender, pure-tone average) were investigated in 191 listeners with hearing impairment. Listeners were assigned to one of three groups based on patterns of hearing aid use: full-time use (whenever hearing aids are needed), part-time use (occasional use), or nonuse. Results showed that SPIN scores and listener characteristics were not related to ANL or hearing aid use. However, ANLs were related to hearing aid use. Specifically, full-time hearing aid users accepted more background noise than part-time users or nonusers, yet part-time users and nonusers could not be differentiated. Thus, a prediction of hearing aid use was examined by comparing part-time users and nonusers (unsuccessful hearing aid users) with full-time users (successful hearing aid users). Regression analysis determined that unaided ANLs could predict a listener's success of hearing aids with 85% accuracy.     

Comparison of speech perception in background noise with acceptance of background noise in aided and unaided conditions.

Background noise is a significant factor influencing hearing-aid satisfaction and is a major reason for rejection of hearing aids. Attempts have been made by previous researchers to relate the use of hearing aids to speech perception in noise (SPIN), with an expectation of improved speech perception followed by an increased acceptance of hearing aids. Unfortunately, SPIN was not related to hearing-aid use or satisfaction. A new measure of listener reaction to background noise has been proposed. The acceptable noise level (ANL), expressed in decibels, is defined as a difference between the most comfortable listening level for speech and the highest background noise level that is acceptable when listening to and following a story. The ANL measure assumes that speech understanding in noise may not be as important as is the willingness to listen in the presence of noise. It has been established that people who accept background noise have smaller ANLs and tend to be "good" users of hearing aids. Conversely, people who cannot accept background noise have larger ANLs and may only use hearing aids occasionally or reject them altogether. Because this is a new measure, it was important to determine the reliability of the ANL over time with and without hearing aids, to determine the effect of acclimatization to hearing aids, and to compare the ANL to well-established measures such as speech perception scores collected with the SPIN test. Results from 50 listeners indicate that for both good and occasional hearing aid users, the ANL is comparable in reliability to the SPIN test and that both measures do not change with acclimatization. The ANLs and SPIN scores are unrelated. Although the SPIN scores improve with amplification, the ANLs are unaffected by amplification, suggesting that the ANL is inherent to an individual and can be established prior to hearing aid fitting as a possible predictor of hearing-aid use.     

Acceptable noise level as a measure of directional hearing aid benefit

An acceptable noise level (ANL) procedure for measuring hearing aid directional benefit was compared with masked speech reception threshold (SRT) and front-to-back ratio (FBR) procedures. ANL is the difference between the most comfortable listening level and the maximum accepted background noise level while listening to speech. Forty adult subjects wearing their own binaural hearing aids were evaluated in omnidirectional and directional modes. The subjects were fitted with a variety of hearing aids by clinical audiologists, independent of the study. For each procedure, speech and noise were presented through loudspeakers located at 0 degrees and 180 degrees azimuth, respectively. Mean ANL (3.5 dB), SRT (3.7 dB), and FBR (2.9 dB) directional benefits were not significantly different. The ANL and masked SRT benefits were significantly correlated. The ANL appears to be a quick, clinician/user friendly procedure for measuring hearing aid directional benefit.     

Acceptance of background noise levels in bilingual (Korean-English) listeners

The acceptable noise level (ANL) is the maximum amount of background noise that listeners are willing to accept while listening to speech. ANL has not been studied in listeners who use languages other than English. The purpose of this study was to explore whether ANLs obtained from Korean listeners in both English and Korean were comparable to ANLs obtained from monolingual English listeners. The results showed that ANLs obtained in English (ANL-E) did not differ significantly for the bilingual and monolingual listeners. Additionally, a cross-language comparison, within bilinguals, showed that ANLs obtained using Korean (ANL-K) speech stimuli were not significantly different from ANL-E. Finally, speech perception in noise did not correlate with ANLs in English or Korean for the bilingual listeners. Results suggest that the ANL measure is language independent within bilinguals and may be of potential clinical use in minority language groups.     

The effects of speech presentation level on acceptance of noise in listeners with normal and impaired hearing.

PURPOSE: To compare the effects of speech presentation level on acceptance of noise in listeners with normal and impaired hearing. METHOD: Participants were listeners with normal (n = 24) and impaired (n = 46) hearing who were matched for conventional acceptable noise level (ANL). ANL was then measured at 8 fixed speech presentation levels (40, 45, 50, 55, 60, 65, 70, and 75 dB HL) to determine if global ANL (i.e., ANL averaged across speech presentation levels) or ANL growth (i.e., the slope of the ANL function) varied between groups. RESULTS: The effects of speech presentation level on acceptance of noise were evaluated using global ANLs and ANL growth. Results showed global ANL and ANL growth were not significantly different for listeners with normal and impaired hearing, and neither ANL measure was related to pure-tone average for listeners with impaired hearing. Additionally, conventional ANLs were significantly correlated with both global ANLs and ANL growth for all listeners. CONCLUSION: These results indicate that the effects of speech presentation level on acceptance of noise are not related to hearing sensitivity. These results further indicate that a listener's conventional ANL was related to his or her global ANL and ANL growth.     

Listeners who prefer monaural to binaural hearing aids

Four patients who preferred monaural as compared with binaural amplification were evaluated. For these patients, audiometric data, recognition performance on a dichotic digit task, and monaural and binaural hearing aid performance using four amplification strategies (National Acoustic Laboratories-Revised, a speech in noise algorithm, multiple-microphone arrays, and frequency modulated [FM]) are described. The results of dichotic testing using a one-, two-, and three-pair dichotic digit task in free- and directed-recall conditions indicated a left-ear deficit for all subjects that could not be explained by peripheral auditory findings or by a cognitive-based deficit. The results of soundfield testing using a speech in multitalker babble paradigm indicated that when listening in noise, there was little difference between aided and unaided word-recognition performance, suggesting that the binaural hearing aids originally fit for each patient were not providing substantial benefit when listening in a competing babble background. Word-recognition performance when aided monaurally in the right ear was superior to performance when aided monaurally in the left ear and when aided binaurally. The only successful binaural amplification strategy was the FM system. The results indicate that listeners with an auditory-based deficit in dichotic listening may function better with a monaural hearing aid fitting or with an assistive listening device such as an FM system. The findings also suggest that a test of dichotic listening is an important component in the evaluation of patients being considered for amplification.     

可接受噪声级测试在单、双耳佩戴助听器效果评估中的应用

目的 通过比较双侧中重度听力损失患者在单、双耳助听下的可接受噪声级(acceptable noise level,ANL),探讨ANL对助听器验配及预测助听效果的作用.方法 选取15例双侧中重度听力损失患者,分别测得双耳未助听、左耳助听、右耳助听和双耳助听状态下的最舒适响度级(most comfortable levels,MCL)、最大背景噪声级(background noise level,BNL),并计算得到ANL值(ANL=MCL-BNL),对结果进行统计学分析.结果 15例受试者双耳未助听、左耳助听、右耳助听及双耳助听四种状态下测得的ANL值分别为18.87±5.26、12.60±2.47、12.00±2.90、5.13±1.25 dB S/N;MCL值分别为80.40±9.28、63.73±5.15、62.27±5.36、61.80±6.05 dB HL;BNL值分别为61.67±6.14、51.13±3.94、50.27±4.50、56.67±5.16 dB HL;左耳助听与右耳助听下的ANL值差异无统计学意义(P>0.05);单、双耳助听下与未助听的ANL值差异均具有统计学意义(P<0.05);双耳助听状态下ANL值显著低于单耳助听(P<0.05).结论 ANL值较低耳更利于助听器验配,佩戴助听器能有效提高听障患者对噪声的接受能力,并且双耳佩戴助听器的效果明显优于单耳.     

Acceptance of noise growth patterns in hearing aid users.

PURPOSE: To examine whether the effects of speech presentation level on acceptance of noise could differentiate full-time, part-time, and nonusers of hearing aids and whether these effects could predict hearing aid use. METHOD: Participants were separated into 3 groups on the basis of hearing aid use: (a) full-time use, (b) part-time use, or (c) nonuse. Acceptable noise levels (ANLs) were measured conventionally and at 8 fixed presentation levels. The effects of presentation level on ANL were determined by calculating global ANL (ANL averaged across presentation level) and ANL growth (slope of the ANL function). RESULTS: Global ANLs were smaller for full-time users than for part-time users and nonusers; however, global ANLs were not different for part-time users and nonusers. ANL growth differentiated full-time users from nonusers only. Conventional ANL predicted hearing aid use with 68% accuracy. Compared with conventional ANL, the accuracy of the prediction for global ANL and ANL growth decreased, and the accuracy of the prediction at presentation levels of 65 to 75 dB HL was maintained. CONCLUSIONS: Global ANL differentiated the hearing aid groups in the same manner as conventional ANL. The effects of presentation level on acceptance of noise did not considerably increase the accuracy of the prediction compared with conventional ANL. Clinical applications are discussed.     

The effect of speech presentation level on acceptance of background noise in listeners with normal hearing

A method has been established to measure the maximum acceptable background noise level (BNL) for a listener, while listening to speech at the most comfortable listening level (MCL). The acceptable noise level (ANL) is the difference between BNL and MCL. In the present study, the ANL procedure was used to measure acceptance of noise, first, in the presence of speech at MCL and, then, for speech presented at much lower and higher levels in listeners with normal hearing. This study used the term ANL to describe the results obtained at MCL and also at other speech presentation levels. The mean ANL at MCL was 15.5 dB, which is comparable to results obtained by previous investigators. ANL increases systematically with speech presentation level. Mean ANLs ranged from 10.6 dB when speech was presented at 20 dB HL to 24.6 dB when speech was presented at 76 dB HL. The results indicated that the acceptance of noise depends significantly on speech presentation level.     

The acceptance of background noise in adult cochlear implant users.

PURPOSE: The purpose of this study was to determine (a) if acceptable noise levels (ANLs) are different in cochlear implant (CI) users than in listeners with normal hearing, (b) if ANLs are related to sentence reception thresholds in noise in CI users, and (c) if ANLs and subjective outcome measures are related in CI users. METHOD: ANLs and the Hearing in Noise Test (HINT; M. Nilsson, S. Soli, & J. Sullivan, 1994) were examined in 9 adult CI users and 15 adult listeners with normal hearing. In addition, the Abbreviated Profile of Hearing Aid Benefit (APHAB; R. M. Cox & G. C. Alexander, 1995) and a satisfaction questionnaire were administered to CI users only. RESULTS: Results indicated that (a) ANLs were not significantly different for CI users and listeners with normal hearing, (b) ANLs were not correlated with HINT values for either group, (c) ANL was not significantly correlated with APHAB scores, and (d) ANL was significantly correlated with overall CI benefit on the satisfaction questionnaire. CONCLUSIONS: CI users with large ANLs reported more benefit from implants than those with small ANLs. The results of this preliminary study of ANL in CI users suggest that ANL can be used as a tool for evaluating processing in noise in individual CI users.     

Relationship between acceptable noise level and the abbreviated profile of hearing aid benefit.

PURPOSE: This study investigated the relationship between acceptable noise levels (ANLs) and the Abbreviated Profile of Hearing Aid Benefit (APHAB; R. M. Cox & G. C. Alexander, 1995). This study further examined the APHAB's ability to predict hearing aid use. METHOD: ANL and APHAB data were collected for 191 listeners with impaired hearing, separated into 3 groups based on hearing aid use: full-time, part-time, or nonuse. RESULTS: Results demonstrated ANLs were not correlated with APHAB scores. Results further demonstrated 2 of the 4 APHAB subscales (Ease of Communication [EC] and Background Noise [BN]) predicted hearing aid success with 60% accuracy, which is 25% poorer than that observed using the ANL alone. When combining the ANL with the EC and BN subscales, accuracy of the prediction increased to 91%. Lastly, 3 of the 4 APHAB subscales (EC, BN, and Reverberation) enhanced the present prediction of hearing aid use for patients with mid-range ANLs. CONCLUSIONS: These results indicate that ANLs and APHAB scores provide unique information regarding hearing aid use. These results further indicate that the prediction can be enhanced by administering both the ANL and the EC and BN APHAB subscales. Lastly, some of the ambiguity of the prediction of hearing aid use for listeners with mid-range ANLs may be eliminated.     

Acceptable noise level: reliability measures and comparison to preference for background sounds

The present study (1) assessed the reliability of the acceptable noise level (ANL) measure using speech-spectrum and speech-babble noises as the competing stimuli, and (2) investigated the relationship between ANL and preference for background sounds in 30 young adults with normal hearing sensitivity. Listeners were evaluated during three test sessions approximately one week apart. Results demonstrated that ANLs are highly reliable over short periods of time, independent of the background noise distraction. Mean ANLs, however, were affected by type of background noise distraction, indicating ANLs obtained using different competing stimuli should not be compared directly. Results further demonstrated that participants' ratings of preference for background sound were consistent over time; however, listeners' preference for background sound was not related to their acceptance of background noise (i.e., ANL). This may indicate listeners cannot accurately assess their ability to accept background sounds, at least with the questionnaire used in the present study.     

The effects of changes in head angle on auditory and visual input for omnidirectional and directional microphone hearing aids

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 degrees, 20 degrees, and 40 degrees. Results indicated improvement in speech recognition performance with changes in head angle for the auditory-only presentation mode at the 20 degrees and 40 degrees head angles when compared to 0 degrees. Improvement in speech recognition performance for the auditory + visual mode was noted for the 20 degrees head angle when compared to 0 degrees. Additionally, a decrement in speech recognition performance for the auditory + visual mode was noted for the 40 degrees head angle when compared to 0 degrees. 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.     

Assessing binaural/bimodal advantages using auditory event-related potentials in subjects with cochlear implants

Objective

To assess the advantage of binaural and bimodal hearing for subjects with cochlear implant (CI) using auditory event-related potentials as well as speech perception tests.

Subjects and methods

The subjects comprised four binaural CI users (CI/CI group) and eleven bimodal CI users, who wore a hearing aid (HA) contralaterally (CI/HA group). All subjects had used binaural or bimodal fitting for over 6 months. Their speech perception was examined in a quiet environment using monosyllabic words. Late cortical waves were measured while subjects were engaged in an oddball task of 1 kHz frequent and 2 kHz rare tone stimuli. The latencies of event-related potential (N1, N2, P3) were compared for monaural, binaural, and bimodal hearing conditions.

Results

Significantly (p < 0.01, paired t-test) better speech perception for monosyllabic words was found for both binaural and bimodal hearing than monaural hearing. The latency of N1 did not significantly change for either binaural or bimodal hearing. On the other hand, the latency of N2 was significantly (p < 0.01, paired t-test) shorter for binaural and bimodal hearing than for monaural hearing. The latency of P3 was shorter for binaural and bimodal hearing than monaural hearing in all subjects, and the difference was statistically significant in both CI/CI and CI/HA groups (p < 0.01, paired t-test).

Conclusions

Better speech perception was obtained for binaural and bimodal hearing than for monaural hearing in CI subjects. The results obtained in the comparison of P3 latency agreed with that of speech perception. Thus, using bilateral hearing devices is recommended for CI subjects. We also found that event-related potentials were useful as an objective tool to assess the advantage of binaural and bimodal hearing for CI subjects.     

Acceptable noise level (ANL) with Danish and non-semantic speech materials in adult hearing-aid users

Abstract Objective: The acceptable noise level (ANL) test is used for quantification of the amount of background noise subjects accept when listening to speech. This study investigates Danish hearing-aid users' ANL performance using Danish and non-semantic speech signals, the repeatability of ANL, and the association between ANL and outcome of the international outcome inventory for hearing aids (IOI-HA). Design: ANL was measured in three conditions in both ears at two test sessions. Subjects completed the IOI-HA and the ANL questionnaire. Study sample: Sixty-three Danish hearing-aid users; fifty-seven subjects were full time users and 6 were part time/non users of hearing aids according to the ANL questionnaire. Results: ANLs were similar to results with American English speech material. The coefficient of repeatability (CR) was 6.5-8.8 dB. IOI-HA scores were not associated to ANL. Conclusions: Danish and non-semantic ANL versions yield results similar to the American English version. The magnitude of the CR indicates that ANL with Danish and non-semantic speech materials is not suitable for prediction of individual patterns of future hearing-aid use or evaluation of individual benefit from hearing-aid features. The ANL with Danish and non-semantic speech materials is not related to IOI-HA outcome.     

Differences in responses from the cochleae and central nervous systems of females with low versus high acceptable noise levels

Studies of acceptable noise level (ANL) consistently report large intersubject variability in acceptance of background noise while listening to speech. This variability is not related to age, gender, hearing sensitivity, type of background noise, speech perception in noise performance, or efferent activity of the medial olivocochlear pathway. An exploratory study was conducted to determine if differences in aggregate responses from the peripheral and central auditory system can account for intersubject variability in ANL. Click-evoked otoacoustic emissions (CEOAEs), binaural auditory brainstem responses (ABRs), and middle latency responses (MLRs) were measured in females with normal hearing with low (n = 6) versus high (n = 7) ANLs. Results of this preliminary study indicate no differences between the groups for CEOAEs or waves I or III of the ABR. Differences between the two groups emerge for the amplitudes of wave V of the ABR and for the Na-Pa component of the MLR, suggesting that physiological variations arising from more central regions of the auditory system may mediate background noise acceptance.     

The impact of head angle on monaural and binaural performance with directional and omnidirectional hearing aids

OBJECTIVE: To evaluate the impact of head turn and monaural and binaural fittings on the sentence reception thresholds of hearing-impaired listeners wearing directional and omnidirectional hearing aids. DESIGN: Sentence reception thresholds were measured for 20 listeners fit monaurally and binaurally with behind-the-ear hearing aids set in both directional and omnidirectional modes. All listeners exhibited symmetrical, sloping, sensorineural hearing loss. The aided performance across these four fittings was evaluated for three different head and body angles. The three angles reflected body turns of 0 degrees, 15 degrees, and 30 degrees as measured relative to the primary sound source, with 0 degrees denoting the listener directly facing the sound source. Listeners were instructed to keep their heads in a fixed horizontal position and turn their heads and bodies to face visual targets at the three test angles. Sentences from the Hearing in Noise Test presented with a background of five, spatially separated, uncorrelated samples of cafeteria noise served as test material. All testing was performed in a moderately reverberant (Rt = 631 msec) "living room" environment. RESULTS: Participants generally performed significantly better when fit with directional versus omnidirectional hearing aids, and when fit binaurally versus monaurally across test conditions. The measured "binaural advantage" was reduced with increasing head angle. Participants performed significantly better with a 30 degree head angle than when directly facing the primary speaker. This "head turn advantage" was most prominent for monaural (versus binaural) conditions. Binaural and head turn advantages were not significantly different across directional and omnidirectional modes. CONCLUSIONS: These data provide additional support for the use of directional hearing aids and binaural amplification to improve speech intelligibility in noisy environments. The magnitude of these advantages was similar to that reported in previous investigations. The data also showed that hearing aid wearers achieved significantly better speech intelligibility in noise by turning their heads and bodies to a position in which they were not directly facing the sound source. This head turn advantage was in good agreement with the increase in Directivity Index with head turn and reflected the fact that hearing aids are generally most sensitive to sounds arriving from angles other than directly in front of the hearing aid wearer. Although these data suggest that many monaural hearing aid wearers may significantly improve speech intelligibility in noise through the use of head turn, the interaction between this advantage and the potential loss of visual cues with head turn is unknown.     

The relationship of locus of control,self-control,and acceptable noise levels for young listeners with normal hearing

Abstract

Objective: Background noise acceptance while listening to speech, assessed via the acceptable noise level (ANL) measure, has been shown to be an accurate predictor of hearing-aid success. No specific listener characteristics have been identified as being related to a listener's ability to accept background noise. The purpose of this study was to determine whether or not locus of control and self-control are related to ANL. Design: Correlational design. Study sample: Participants were seventy young adults (21 male, 49 female; aged 19 to 39 years) with normal hearing. Participants completed psychological profiles that evaluated locus of control and self-control and their ANLs were measured. Results: Results revealed correlations between ANL and self-control. Listeners with higher levels of self-control accepted more background noise than listeners with lower levels of self-control. Conclusions: This research suggests that exercises aimed at strengthening a listener's auditory self-control may lead to improved background noise acceptance. Improvement in background noise acceptance could lead to improved hearing-aid success. Future research should explore these possibilities.     

Acceptable noise level (ANL) with Danish and non-semantic speech materials in adult hearing-aid users

Abstract

Objective: The acceptable noise level (ANL) test is used for quantification of the amount of background noise subjects accept when listening to speech. This study investigates Danish hearing-aid users’ ANL performance using Danish and non-semantic speech signals, the repeatability of ANL, and the association between ANL and outcome of the international outcome inventory for hearing aids (IOI-HA). Design: ANL was measured in three conditions in both ears at two test sessions. Subjects completed the IOI-HA and the ANL questionnaire. Study sample: Sixty-three Danish hearing-aid users; fifty-seven subjects were full time users and 6 were part time/non users of hearing aids according to the ANL questionnaire. Results: ANLs were similar to results with American English speech material. The coefficient of repeatability (CR) was 6.5–8.8 dB. IOI-HA scores were not associated to ANL. Conclusions: Danish and non-semantic ANL versions yield results similar to the American English version. The magnitude of the CR indicates that ANL with Danish and non-semantic speech materials is not suitable for prediction of individual patterns of future hearing-aid use or evaluation of individual benefit from hearing-aid features. The ANL with Danish and non-semantic speech materials is not related to IOI-HA outcome.