Comparison of the CAM2A and NAL-NL2 hearing-aid fitting methods for participants with a wide range of hearing losses

Objective: To compare preferences for sounds processed via a simulated five-channel compression hearing aid fitted using CAM2A and NAL-NL2. Design: Within a trial, the same segment of sound was presented twice, once with CAM2A settings and once with NAL-NL2 settings, in random order. The participant indicated which one was preferred and by how much. Stimuli included female and male speech in quiet and four types of music. The compression speed was slow or fast and the input sound level was 50, 65, or 80 dB SPL. Study sample: Sixteen experienced hearing-aid users with a wide range of sensorineural hearing losses. Results: For both compression speeds, CAM2A was slightly preferred over NAL-NL2 for input levels of 65 and 80 dB, but NAL-NL2 was slightly preferred at 50 dB SPL. Conclusions: Preferences for CAM2A relative to NAL-NL2 vary with input level. The results suggest that preferences for CAM2A might be increased by using lower gains for high frequencies and low input levels.     

Variation in preferred gain with experience for hearing-aid users

This study aimed to determine whether gain adaptation occurs, and at which frequency bands, among new hearing aid (HA) users. Fifty new and 26 experienced HA users were fitted with three listening programs (NAL-NL1 and NAL-NL1 with low- and high-frequency cuts) in the same hearing instrument family. Real-life gain preferences and comfortable loudness levels were measured one, four, and 13 months post-fitting for the new HA users, and one month post-fitting for the experienced HA users. Relative to experienced HA users, new HA users preferred progressively less overall gain than prescribed as the hearing loss became more severe. Gain adaptation occurred in new HA users with greater hearing loss, but was not complete 13 months post-fitting, and was not explained by changes in loudness perception. Preferences for a high-frequency gain cut by half of all study participants could not be predicted from audiological data. Gain adaptation management is recommended for new HA users with more than a mild hearing loss.     

Variation in preferred gain with experience for hearing-aid users

This study aimed to determine whether gain adaptation occurs, and at which frequency bands, among new hearing aid (HA) users. Fifty new and 26 experienced HA users were fitted with three listening programs (NAL-NL1 and NAL-NL1 with low- and high-frequency cuts) in the same hearing instrument family. Real-life gain preferences and comfortable loudness levels were measured one, four, and 13 months post-fitting for the new HA users, and one month post-fitting for the experienced HA users. Relative to experienced HA users, new HA users preferred progressively less overall gain than prescribed as the hearing loss became more severe. Gain adaptation occurred in new HA users with greater hearing loss, but was not complete 13 months post-fitting, and was not explained by changes in loudness perception. Preferences for a high-frequency gain cut by half of all study participants could not be predicted from audiological data. Gain adaptation management is recommended for new HA users with more than a mild hearing loss.     

Optimal gain control step sizes for bimodal stimulation

Objective: Cochlear implants (CI) and hearing aids (HA) have a gain control that allows the bimodal user to change the loudness. Due to differences in dynamic range between CI and HA, an equal change of the gains of the two devices results in different changes in loudness. The objective was to relate and individualise the step sizes of the loudness controls to obtain a similar perceptual effect in the two ears. Design: We used loudness models parametrised for individual users to find a relation between the controls of the CI and the HA such that each step resulted in an equal change in loudness. We conducted loudness balancing experiments to validate the results. Study sample: Eleven bimodal users of whom six were tested in a prior study. Results: The difference between the optimal gain from the loudness balancing procedure and actual gain was 3.3?dB when the new relation was applied. In contrast, the difference was 8?dB if equal step sized were applied at both sides. Conclusion: We can relate the controls such that each step results in a similar loudness difference.     

Sounds perceived as annoying by hearing-aid users in their daily soundscape

Abstract

Background: The noises in modern soundscapes continue to increase and are a major origin for annoyance. For a hearing-impaired person, a hearing aid is often beneficial, but noise and annoying sounds can result in non-use of the hearing aid, temporary or permanently. Objective: The purpose of this study was to identify annoying sounds in a daily soundscape for hearing-aid users. Design: A diary was used to collect data where the participants answered four questions per day about annoying sounds in the daily soundscape over a two-week period. Study sample: Sixty adult hearing-aid users. Results: Of the 60 participants 91% experienced annoying sounds daily when using hearing aids. The annoying sound mentioned by most users, was verbal human sounds, followed by other daily sound sources categorized into 17 groups such as TV/radio, vehicles, and machine tools. When the hearing-aid users were grouped in relation to age, hearing loss, gender, hearing-aid experience, and type of signal processing used in their hearing aids, small and only few significant differences were found when comparing their experience of annoying sounds. Conclusions: The results indicate that hearing-aid users often experience annoying sounds and improved clinical fitting routines may reduce the problem.