Acceptable Noise Level Measure Research Articles

Test–retest Reliability of Acceptable Noise Level in Kannada-speaking Children with Normal Hearing Sensitivity

Introduction: Understanding speech accurately in the presence of noise is crucial for the development of learning speech, language, and educational skills in children. There are various audiological procedures available to check the ability of speech perception in the presence of noise. Acceptable noise level (ANL) measures the individual’s ability to tolerate the amount of background noise while listening to speech. Though, ANL has been shown to be clinically effective measure in children and adults its test- retest reliability in children is not well understood. Hence the present study was carried out to establish ANL using Kannada stimuli in native Kannada speaking children with normal hearing sensitivity and to check the test-retest reliability of the measure in them. Method: The study included a total of 61 native Kannada speaking children within the age range of 9-12years. Most Comfortable Level (MCL) and Background Noise Level (BNL) were established using standard procedures. The ANL was obtained by subtracting the BNL value with MCL for each participant. Results: The results revealed that there exists unacceptable reliability in MCL, BNL and ANL measures in native Kannada speaking children with normal hearing sensitivity using Kannada speech stimulus. This indicates that the ANL needs to be interpreted with caution in Children. Conclusion: The current study findings highlight on the importance of exploring these measures in children of various age groups to understand the developmental trend and age of maturation of ANL measure.

Acceptable Noise Levels and Preferred Signal-to-noise Ratios for Speech and Music.

The objective of this study was to evaluate the influence of music versus speech on a listener's signal-to-noise ratio (SNR) preferences when listening in a noise background. SNR preferences were quantified using acceptable noise level (ANL) and preferred SNR metrics. The measurement paradigm for ANL allows the listener to adjust the level of background noise while listening to the target at their most comfortable loudness level. A higher ANL indicates less tolerance for noise and a lower ANL indicates high tolerance for noise. The preferred SNR is simply the SNR the listener prefers when attending to a target in a fixed-amount (level) of background noise. In contrast to the ANL, the listener does not have control over the noise. Rather, they are only able to manipulate the target level. The first aim of the study was to determine if listeners' tolerances for noise, quantified using the ANL, when listening to music is different from that when listening to speech. The second aim of the study was to determine if listeners' tolerances for noise, quantified using their preferred SNR, when listening to music is different from that when listening to speech. The third aim of the study was to quantify the relationship between ANL and preferred SNR. Ninety-nine normal-hearing, native-English speakers participated in this study. The ANL and preferred SNR were measured for speech and music targets. Music targets included two variations (with lyrics and without lyrics) of the song "Rocky Top." Measurements were made in the sound field at 0° azimuth, 1.5 m from a loud speaker. For both ANL and preferred SNR, targets were presented in 12-talker babble noise. The level of the noise was adjusted by the listener during ANL measurement but was fixed in level during the preferred SNR measurement (75 dB A). Repeated-measures analysis of variance was performed to identify any significant effect of target on the ANL and preferred SNR. Correlation analysis was performed to evaluate the relationship between ANL and preferred SNR. Findings demonstrate a significant effect of target on ANL and preferred SNR. ANLs were highest for speech (mean = 7.2 dB), followed by music with lyrics (6.1 dB), and music without lyrics (2.5 dB). Preferred SNRs were highest for music with lyrics (mean = 2.3 dB), followed by speech (1.2 dB), and music without lyrics (-0.1 dB). A listener's ANL for a given target was strongly correlated with their ANL for a different target (the same was true for preferred SNR); however, ANL for a given target was not a statistically significant predictor of preferred SNR for the same target. When listening in a background of noise, the listener's tolerance for noise depends on the target to which they are attending, whether music or speech. This dependence is especially evident for ANL measures, and less so for preferred SNR measures. Despite differences in ANL and preferred SNR across targets, a listener's ANL and preferred SNR for one target predicts their ANL and preferred SNR, respectively, for a different target. The lack of correlation between ANL and preferred SNR suggests different mechanisms underly these listener-preference metrics.

Acceptable Noise Levels Determined by Traditional and Self-Assessed Methods.

Many apps have been developed for users to screen their hearing in their own home. The purpose of this study was to investigate the validity and efficiency of a self-assessed acceptable noise level (ANL) in comparison to the traditional ANL measurements. A within-subject repeated measures research design was utilized. Sixty-two adults with normal hearing were recruited from Auburn University and the surrounding community. ANLs were measured utilizing the traditional measurement as well as the self-assessed ANL via the Unitron uHear app. Within-subject repeated measures of variance revealed no significant differences between traditional ANL measurements and self-assessed ANL measurements. Significant differences were found for time required for testing in each condition, revealing self-assessed testing to be significantly faster. The self-assessed ANL measurement via the Unitron uHear app is a valid and efficient measurement of ANL in adults with normal hearing.

Assessment of acceptable noise level in unilateral hearing aid users

Background and Aim: It is well known that hearing aid fitting is an effective approach to improve the communication ability of hearingimpaired people. In the past, most of the hearing aids were fitted unilaterally rather than bilaterally. Whereas the unilateral hearing aid fitting improves verbal communication partially, it causes late-onset auditory deprivation. The main aim of this study is to investigate the ANL for each ear among the users with unilateral hearing aid experience. Methods: A total of 23 participants were recruited (14 females, 9 males). The mean age was 74.65 years (ranged from 41 to 83). All subjects had bilateral symmetric sensorineural hearing loss. The most comfortable level (MCL), Background Noise Level (BNL), and acceptable noise level (ANL) were measured for ear with amplification experience and ear without experience. Results: MCL, BNL and ANL in the aided ear was 82.22, 73.48 and 8.74 respectively, in addition in the unaided ear the results for MCL, BNL and ANL was 81.78, 72.13 and 9.65 respectively. Comparing the mean values of MCL, BNL and ANL between two ears showed no significant difference. Conclusion: There was not any difference for BNL and ANL measures Keywords: Bilateral hearing loss; acceptable noise level; late onset auditory deprivation; Hearing aid

Relationship Between Auditory and Visual Noise Acceptance in Normal-Hearing Listeners.

Research has shown that hearing aid acceptance is closely related to how well an individual tolerates background noise, regardless of improved speech understanding in background noise. The acceptable noise level (ANL) test was developed to quantify background noise acceptance. The ANL test measures a listener's willingness to listen to speech in noise rather than their ability to understand speech in noise, and is clinically valuable as a predictor of hearing aid success. Noise acceptance is thought to be mediated by central regions of the nervous system, but the underlying mechanism of noise acceptance is not well understood. Higher order central efferent mechanisms may be weaker and/or central afferent mechanisms are more active in listeners with large versus small ANLs. Noise acceptance, therefore, may not be limited to the auditory modality but observable across modalities. We designed a visual-ANL test, as a parallel of the auditory-ANL test, to examine the relations between auditory and visual noise acceptance. A correlational design. Thirty-seven adults between the ages of 21 and 30 years with normal hearing participated in this study. All participants completed the standard auditory-ANL task, the visual-ANL task developed for this study, reception thresholds for sentences using the hearing in noise test, and visual sentence recognition in noise using the text reception threshold test. Correlational analyses were performed to evaluate the relations between and among the ANL and perception tasks. Auditory- and Visual-ANLs were correlated; those who accepted more auditory noise were also those who accepted more visual noise. Auditory and visual perceptual measures were also correlated, demonstrating that both measures reflect common processes underlying the ability to recognize speech in noise. Finally, as expected, noise acceptance levels were unrelated to perception in noise across modalities. The results of this study support our hypothesis that noise acceptance may not be unique to the auditory modality, specifically, that the common variance shared between the two ANL tasks, may reflect a shared general perceptual or cognitive mechanism that is not specific to the auditory or visual domains. These findings also support that noise acceptance and speech recognition reflect different aspects of auditory and visual perception. Future work will relate these ANL measures with central tasks of inhibition and include hearing-impaired individuals to explore the mechanisms underlying noise acceptance.

Effect of long-term exposure to traffic noise on acceptable noise level measures in traffic police officers

Introduction: The acceptable noise level (ANL) measure is a subjective way of identifying how much of noise a person is able to put up with while listening to speech. Individuals with low ANL were observed to be satisfied hearing users than the individuals with high ANL. However, the reason for large individual variations of the measure is still not well understood. Exposure to noise may be one such factor that would affect the ANL which was never explored. Among the individuals who are exposed to noise, majority are exposed to occupational noise. Traffic police is such a working population who is exposed continuously to traffic noise during their duty hours. Hence, the present study was planned to investigate ANL measures in traffic police officers that might further provide insight toward the heterogeneity of the measure. Methods: A total of 38 participants were divided into two groups. Group 1 consisted of 19 traffic police officers with minimum of 5 years of job experience and Group 2 consisted of normal hearing individuals without any noise exposure. All the participants underwent routine audiological evaluations followed by ANL testing. Results: The mean ANL obtained in both the groups was statistically compared. The results revealed that the traffic police officers yielded better ANLs than participants in Group 2. Conclusion: This ability of traffic police officers to put up with more noise while listening to speech may be attributed to their long-standing experience in listening to wanted signals in noise.

Comparing Loudness Tolerance and Acceptable Noise Level in Listeners With Hearing Loss.

The present study was a follow-up investigation to a previous study exploring the relationship between listeners' loudness tolerance and listeners' acceptable noise level among normally hearing adults. The present study compared the same two measures, but data were obtained from listeners with hearing loss; 12 adults with sensorineural hearing loss participated in a loudness tolerance measure using a scaling technique initially established for setting hearing aid output limits, in addition to an acceptable noise level measure. The acceptable noise level procedure used in this study quantified the listeners' acceptance of background noise while listening to speech. As with the research involving listeners with normal hearing, the Pearson correlation procedure indicated a lack of any statistically significant correlation between the two measures.

Encoding of speech sounds at auditory brainstem level in good and poor hearing aid performers

IntroductionHearing aids are prescribed to alleviate loss of audibility. It has been reported that about 31% of hearing aid users reject their own hearing aid because of annoyance towards background noise. The reason for dissatisfaction can be located anywhere from the hearing aid microphone till the integrity of neurons along the auditory pathway. ObjectivesTo measure spectra from the output of hearing aid at the ear canal level and frequency following response recorded at the auditory brainstem from individuals with hearing impairment. MethodsA total of sixty participants having moderate sensorineural hearing impairment with age range from 15 to 65 years were involved. Each participant was classified as either Good or Poor Hearing aid Performers based on acceptable noise level measure. Stimuli /da/ and /si/ were presented through loudspeaker at 65dB SPL. At the ear canal, the spectra were measured in the unaided and aided conditions. At auditory brainstem, frequency following response were recorded to the same stimuli from the participants. ResultsSpectrum measured in each condition at ear canal was same in good hearing aid performers and poor hearing aid performers. At brainstem level, better F0 encoding; F0 and F1 energies were significantly higher in good hearing aid performers than in poor hearing aid performers. Though the hearing aid spectra were almost same between good hearing aid performers and poor hearing aid performers, subtle physiological variations exist at the auditory brainstem. ConclusionThe result of the present study suggests that neural encoding of speech sound at the brainstem level might be mediated distinctly in good hearing aid performers from that of poor hearing aid performers. Thus, it can be inferred that subtle physiological changes are evident at the auditory brainstem in a person who is willing to accept noise from those who are not willing to accept noise.

Acceptable Noise Level Measured using Monitored Live Voice: A Pilot Study

Objective: Background noise is a significant contributor to poor speech understanding for listeners with normal hearing. It creates an even greater challenge for listeners with hearing loss. Those with hearing loss who use hearing aids often complain of background noise. Specifically, background noise is the main complaint among hearing aid users when trying to follow a conversation. Half of the conversations occur in environments with some background present. The acceptable noise level (ANL) is a measure that attempts to quantify listener preference of background noise when listening to speech. Its use can contribute to clinicians and those with hearing loss by predictively differentiating full time hearing aid wearers from part time wearers or those who reject hearing aids. Thus, the ANL can be a valuable tool for the fitting of and counseling related to hearing aids. However, the ANL is not widely utilized by clinicians in the field. One of the possible reasons for this may be a factor of convenience in performing the ANL measurement with an audiometer alone, as a test easier for clinicians to administer may be more acceptable. Methods: This pilot study compared differences in ANLs from eighteen listeners with normal hearing obtained using a commercially available recorded monologue with a monitored live voice (MLV) presentation of the same monologue. Results: Statistical procedures for data analysis included a Paired Samples T-test to look for differences between the means of the data collected with the two signal types. Additionally, regression analysis using the Pearson Product Correlation was implemented to provide an illustration of the relationship between the two groups of data. Results indicated a strong correlation, but significant difference between the two presentation modes. Conclusion: Although the means differed to the level of statistical significance, the difference may not be considered to have reached the level of minimal clinical importance. Since the ANL has the potential of being a valuable clinical tool, further research into the ANL measure obtained with MLV presentation will be needed.

Measurement of Acceptable Noise Level with Background Music.

Background and ObjectivesAcceptable noise level (ANL) is a measure of the maximum background noise level (BNL) that a person is willing to tolerate while following a target story. Although researchers have used various sources of target sound in ANL measures, a limited type of background noise has been used. Extending the previous study of Gordon-Hickey & Moore (2007), the current study determined the effect of music genre and tempo on ANLs as possible factors affecting ANLs. We also investigated the relationships between individual ANLs and the familiarity of music samples and between music ANLs and subjective preference.Subjects and MethodsForty-one participants were seperated into two groups according to their ANLs, 29 low-ANL listeners and 12 high-ANL listeners. Using Korean ANL material, the individual ANLs were measured based on the listeners' most comfortable listening level and BNL. The ANLs were measured in six conditions, with different music tempo (fast, slow) and genre (K-pop, pop, classical) in a counterbalanced order.ResultsOverall, ANLs did not differ by the tempo of background music, but music genre significantly affected individual ANLs. We observed relatively higher ANLs with K-pop music and relatively lower ANLs with classical music. This tendency was similar in both low-ANL and high-ANL groups. However, the subjective ratings of music familiarity and preference affected ANLs differently for low-ANL and high-ANL groups. In contrast to the low-ANL listeners, the ANLs of the high-ANL listeners were significantly affected by music familiarity and preference.ConclusionsThe genre of background music affected ANLs obtained using background music. The degree of music familiarity and preference appears to be associated with individual susceptibility to background music only for listeners who are greatly annoyed by background noise (high-ANL listeners).

Acceptance noise level: effects of the speech signal, babble, and listener language.

The acceptable noise level (ANL) measure has gained much research/clinical interest in recent years. The present study examined how the characteristics of the speech signal and the babble used in the measure may affect the ANL in listeners with different native languages. Fifteen English monolingual, 16 Russian-English bilingual, and 24 Spanish-English bilingual listeners participated. The ANL was obtained in eight conditions varying in the language of the signal (English and Spanish), language of the babble (English and Spanish), and number of talkers in the babble (4 and 12). Test conditions were randomized across listeners. The ANL for each condition was based on a minimum of two trials. Russian-English bilinguals yielded higher ANLs than other listeners; the intergroup difference of 4-5 dB was statistically and clinically significant. Spanish signals yielded significantly higher ANLs than English signals, but this difference of 0.5 dB was clinically negligible. The language and composition of the babble had a significant effect on Russian-English bilinguals, who yielded higher ANLs with the Spanish than English 12-talker babble. The above findings do not fully support the notion that the ANL is language- and population-independent. Clinicians should be aware of possible effects on ANL measures due to listeners' linguistic/cultural background.

The relationship between the acceptance of noise and acoustic environments in young adults with normal hearing: a pilot study.

The acceptable noise level (ANL) indicates how much background noise a listener is willing to accept while listening to speech. The clinical impact and application of the ANL measure is as a predictor of hearing-aid use. The ANL may also correlate with the percentage of time spent in different listening environments (i.e., quiet, noisy, noisy with speech present, etc). Information retrieved from data logging could confirm this relationship. Data logging, using sound scene analysis, is a method of monitoring the different characteristics of the listening environments that a hearing-aid user experiences during a period. The purpose of this study was to determine if the ANL procedure reflects the proportion of time a person spends in different acoustic environments. This was a descriptive quasi-experimental design to collect pilot data in which participants were asked to maintain their regular, daily activities while wearing a data-logging device. After completing the ANL measurement, 29 normal-hearing listeners were provided a data-logging device and were instructed on its proper use. ANL measures were obtained along with the percentage of time participants spent in listening environments classified as quiet, speech-in-quiet, speech-in-noise, and noise via a data-logging device. An analysis of variance using a general linear model indicated that listeners with low ANL values spent more time in acoustic environments in which background noise was present than did those with high ANL values; the ANL data did not indicate differences in how much time listeners spent in environments of differing intensities. To some degree, the ANL is reflective of the acoustic environments and the amount of noise that the listener is willing to accept; data logging illustrates the acoustic environments in which the listener was present. Clinical implications include, but are not limited to, decisions in patient care regarding the need for additional counseling and/or the use of digital noise reduction and directional microphone technology.

Acceptable noise level in bilinguals: Consideration of signal and masker effects

This study explores how bilingual listeners’ acceptable noise level (ANL) may be affected by the language of the signal, language of the masker, and talkers in the masker. ANL measures how much a listener tolerates background noise while listening to running speech. It differs from conventional speech recognition tasks in that it does not concern one’s ability to comprehend speech. Hence, ANLs are expected to be relatively free of bilingual background. In this study, the signal (running passages from New York State Department of Motor Vehicles driving manual) was presented in two languages (English versus Spanish). The maskers (Auditec babbles) were manipulated in language (English versus Spanish) and number of talkers (four versus twelve). Additionally, three groups of 12 listeners participated in the study—monolingual English, Spanish-English bilingual, and Russian-English bilingual. A 3×2×2×2 mixed, repeated design was carried out with listener group as the between-subjects factor, and signal and masker language and number factors as the within-subjects factors. Preliminary findings reveal a non-significant effect for all four factors; however, a marginally significant four-way interaction (p = 0.048) invites group wise analysis. Results may help establish new clinical approaches in assessing listeners’ speech perception difficulty in noise, regardless of language background.

An Australian version of the acceptable noise level test and its predictive value for successful hearing aid use in an older population

Objective: The acceptable noise level (ANL), a measure of noise tolerance, has been proposed as a predictor for successful hearing aid use. The aims of this study were to obtain normative data, and to evaluate the clinical feasibility and predictive value of an Australian version of the ANL test in an older population. Design: Repeated ANL measurements were presented diotically using earphones. All participants provided demographic information and hearing aid owners were asked about their aid use. Study sample: A total of 290 older adults were assessed; 166 participants had a hearing impairment and 96 owned a hearing aid. Results: The mean ANL was lower than previously reported. While age and gender had no effect on ANL, a significant, but weak, correlation was found between ANL and hearing loss. The test-retest reliability showed the results were clinically unreliable. In addition, the ANL did not predict hours or pattern of hearing aid use. Conclusions: While the Australian ANL test showed several similar characteristics to previous versions of the test, low test-retest reliability raised questions about its clinical value as a predictor for long-term hearing aid use.

Does the acceptable noise level (ANL) predict hearing-aid use?

Objective: It has been suggested that individuals have an inherent acceptance of noise in the presence of speech, and that different acceptance of noise results in different hearing-aid (HA) use. The acceptable noise level (ANL) has been proposed for measurement of this property. It has been claimed that the ANL magnitude can predict hearing-aid use patterns. Many papers have been published reporting on different aspects of ANL, but none have challenged the predictive power of ANL. The purpose of this study was to discuss whether ANL can predict HA use and how more reliable ANL results can be obtained. Design: Relevant literature regarding the ANL was found on Medline, Embase, and Google Scholar. Additional information was found as references in the included papers and through personal contacts, for instance when attending audiology conferences. Study sample: Forty-five papers published in peer reviewed journals as well as a number of papers from trade journals, posters and oral presentations from audiology conventions. Conclusions: An inherent acceptance of noise in the presence of speech may exist, but no method for precise measurement of ANL is available. The ANL model for prediction of HA use has yet to be proven valid.

Acceptable Noise Levels in Preschool Children with Normal Hearing

The acceptable noise level (ANL) measure is an indicator of hearing aid use. The majority of research in this area has focused primarily on adults. Research using school-aged listeners, specifically 8 and 12 yr old children, demonstrated that the average ANL values, standard deviations (SDs), and distribution of ANL values for these children were similar to those of adult listeners. Additionally, the ANL measure is reliable over time, even in school-aged listeners. Although ANL values from adult and school-aged listeners have been investigated, no research to date has been conducted using preschool children. The purpose of the present study was to determine if ANLs could be obtained in preschool children, aged 4 and 5 yr, with normal hearing. This study also aimed to investigate the reliability and distribution of ANL measurements from preschool children, as well as any effect that background noise might present in the listening environment. Seated in a sound-treated test suite, listeners were tasked with adjusting speech stimuli to their most comfortable listening level; then, with speech present, listeners were tasked with adjusting the background noise to their most acceptable background noise level. Three trials of each measure were averaged and were used to calculate each listener's ANL. ANLs were attempted on 23 children, ages 4 yr (N = 14) to 5 yr (N = 9), with normal hearing. Less than half of the 4 yr old listeners performed the ANL task, whereas all of the 5 yr old listeners completed the task successfully. Good test-retest reliability was found for those preschool children who were able to complete the task. Mean ANLs, SDs, ranges, and distributions demonstrated that these values agree with ANL data collected from older school-aged listeners. Although ANL values were reliably measured in all of the 5 yr old listeners, this was not the case for 4 yr old listeners. ANL values were not reliably obtained from 4 yr old listeners; however, the ANL procedure is appropriate for use for 5 yr old listeners. Furthermore, ANL means, SDs, ranges, and distributions were in agreement with those from older school-aged children and adults, and ANLs in preschool listeners were unaffected by the type of background noise stimuli.

The Effect of Presentation Level on Normal-Hearing and Hearing-Impaired Listeners' Acceptable Speech and Noise Levels

Acceptable noise level (ANL) is a measure of the maximum amount of background noise that a listener is willing to "put up with" while listening to running speech. This test is unique in that it can predict with a high degree of accuracy who will be a successful hearing-aid wearer. Individuals who tolerate high levels of background noise are generally successful hearing-aid wearers, whereas individuals who do not tolerate background noise well are generally unsuccessful hearing-aid wearers. Various studies have been unsuccessful in trying to relate ANLs to listener characteristics or other test results. Presumably, understanding the perceptual mechanism by which listeners determine their ANLs could provide an understanding of the ANL's unique predictive abilities and our current inability to correlate these results with other listener attributes or test results. As a first step in investigating this problem, the relationships between ANLs and other threshold measures where listeners adjust the signal-to-noise ratio (SNR) according to some criterion in a way similar to the ANL measure were examined. RESEARCH DESIGN AND STUDY SAMPLE: Ten normal-hearing and 10 hearing-impaired individuals participated in a laboratory experiment that followed a within-subjects, repeated-measures design. Participants were seated in a sound booth. Running speech and noise (eight-talker babble) were presented from a loudspeaker at 0°, 3 ft in front of the participant. Individuals adjusted either the level of the speech or the level of the background noise. Specifically, with the speech fixed at different levels (50, 63, 75, or 88 dBA), participants performed the ANL task, in which they adjusted the level of the background noise to the maximum level at which they were willing to listen while following the speech. With the noise fixed at different levels (50, 60, 70, or 80 dBA), participants adjusted the level of the speech to the minimum, preferred, or maximum levels at which they were willing to listen while following the speech. Additionally, for the minimum acceptable speech level task, each participant was tested at four participant-specific noise levels, based on his/her ANL results. To emphasize that the speech level was adjusted in these measurements, three new terms were coined: "minimum acceptable speech level" (MinASL), "preferred speech level" (PSL), and "maximum acceptable speech level" (MaxASL). Each condition was presented twice, and the results were averaged. Test order and presentation level were randomized. Hearing-impaired participants were tested in the aided condition only. For most participants, as the presentation level increased, SNRs increased for the ANL test but decreased for the MinASL, PSL, and MaxASL tests. For a few participants, ANLs were similar to MinASLs. For most test conditions, the normal-hearing results were not significantly different from those of the hearing-impaired participants. For most participants, stimulus level affected the SNRs at which they were willing to listen. However, a subset of listeners was willing to listen at a constant SNR for the ANL and MinASL tests. Furthermore, for these individuals, ANLs and MinASLs were roughly equal, suggesting that these individuals may have used the same perceptual criterion for both tests.

Measurement of Acceptable Noise Level and Self-Reported Subjective Disability in Adult Cochlear Implant Users

The present study aimed to compare the acceptable noise levels (ANLs) of normal-hearing listeners (N = 10) and cochlear implant (CI, N = 10) users, depending on the target-talker gender and the number of background competing talkers. The profile of hearing disability of CI users was also determined by the Korean-translated speech, spatial, and qualities of hearing scale (K-SSQ) for CI users. Results showed that the ANLs did not significantly differ between CI users and normal-hearing listeners. For both groups, the effect of target-talker gender (male vs. female) was not significant, whereas the number of background competing talkers (1 to 8 talkers) significantly influenced ANL results. The ANLs of both groups significantly increased as the number of competing talkers was reduced. The greatest distraction from noise was observed when the gender of target and background talkers was matched. This suggests that, regardless of listener groups, all the listeners are more annoyed by background noise when the background speech becomes more meaningful or when the voice of target and competing talkers gets similar. Correlational analyses revealed that the ANLs of CI users were significantly related to the K-SSQ responses on the quality of hearing domain, indicating that CI users who accepted more amount of noise actually reported more improvement on sound quality with CI use.

The equivalence of acceptable noise level (ANL) with English, Mandarin, and non-semantic speech: A study across the U.S. and Taiwan

Objective: Acceptable noise level (ANL) determines the maximum noise level that a listener is willing to accept while listening to speech. The objective of this study was to determine the equivalence of ANL measured using different speech stimuli for native speakers who lived in the U.S. and Taiwan. Design: ANLs were measured using English, Mandarin, and the international speech test signal (ISTS) at each site. The same babble noise was used across speech stimuli. The ANLs were considered equivalent if the difference was unlikely to be greater than 3 dB. Study sample: Thirty adults with normal hearing were recruited at each site. Results: For each site, the equivalence test suggested that the native-language and foreign-language ANLs were equivalent. Between the two sites, ANLs measured using the listener’s native language were also equivalent. Although the ISTS ANL obtained within each site was equivalent to, and highly correlated to, the native-language ANL, the data were unable to confirm the equivalence of the ISTS ANLs obtained from the two sites. Conclusions: The results suggested the possibility of directly comparing ANL measures carried out in different countries using different languages. However, it remains unclear if the ISTS can serve as an international ANL stimulus.

Intertester Reliability of the Acceptable Noise Level

The acceptable noise level (ANL) serves to accurately predict the listener's likelihood of success with amplification. It has been proposed as a pre-hearing aid fitting protocol for hearing aid selection and counseling purposes. The ANL is a subjective measure of the listener's ability to accept background noise. Measurement of ANL relies on the tester and listener to follow the instructions set forth. To date, no research has explored the reliability of ANL as measured across clinicians or testers. To examine the intertester reliability of ANL. A descriptive quasi-experimental reliability study was completed. ANL was measured for one group of listeners by three testers. Three participants served as testers. Each tester was familiar with basic audiometry. Twenty-five young adults with normal hearing served as listeners. Each tester was stationed in a laboratory with the needed equipment. Listeners were instructed to report to these laboratories in a random order provided by the experimenters. The testers assessed most comfortable listening level (MCL) and background noise level (BNL) for all 25 listeners. Intraclass correlation coefficients were significant and revealed that MCL, BNL, and ANLs are reliable across testers. Additionally, one-way ANOVAs for MCL, BNL, and ANL were not significant. These findings indicate that MCL, BNL, and ANL do not differ significantly when measured by different testers. If the ANL instruction set is accurately followed, ANL can be reliably measured across testers, laboratories, and clinics. Intertester reliability of ANL allows for comparison across ANLs measured by different individuals. Findings of the present study indicate that tester reliability can be ruled out as a factor contributing to the disparity of mean ANLs reported in the literature.