Efficacy of Directional Microphones in Hearing Aids Equipped with Wireless Synchronization Technology.

OBJECTIVE: This study aimed to evaluate the use of directionality in hearing aids with wireless synchronization on localization and speech intelligibility in noise. MATERIALS AND METHODS: This study included 25 individuals with bilateral mild to moderate flat sensorineural hearing loss. For the localization experiment, eight loudspeakers (Genelec 8020B) arranged in a circle covering a 0-360° angle and the Cubase 6 software were used for presenting the stimulus. A car horn of 260 ms was presented from these loudspeakers, one at a time, randomly. The listener was instructed to point to the direction of the source. The degree of the localization error was obtained with and without directionality and wireless synchronization options. For speech perception in a noise experiment, signal to noise ratio-50 (SNR-50) was obtained using sentences played through a speaker at a fixed angle of 0°. A calibrated eight-talker speech babble was used as noise and the babble was routed either through 0°, 90°, 270° (through one speaker at a time) or through both 90° and 270° speakers. RESULTS: The results revealed that the conditions where both the wireless synchronization and directionality were activated resulted in a significantly better performance in both localization and speech perception in noise tasks. CONCLUSION: It can be concluded that the directionality in the wireless synchronization hearing aids coordinates with each other binaurally for better preservation of binaural cues, thus reducing the localization errors and improving speech perception in noise. The results of this study could be used to counsel and justify the selection of the directional wireless synchronization hearing aids.

One-year prevalence and risk factors of tinnitus in children with otological problems.

INTRODUCTION: The present study was conducted to find one year prevalence and risk factors of tinnitus in the children (below 18 years) who reported with the ear or hearing related complaint to All India Institute of Speech and hearing, Mysore. METHODS: A retrospective case analysis was carried out by reviewing the case files of those who visited the institute during the above period. RESULTS: The results shown that the tinnitus prevalence was 5.24%. No gender difference was found in children with tinnitus. Further, 79.63% of the children with tinnitus had hearing loss. In addition, 30.23% of the children with tinnitus had mild degree of hearing loss followed by minimal, and moderate degree of hearing loss. Most of these children had conductive, and sensorineural type of hearing loss than mixed type of hearing loss. CONCLUSION: It can be concluded that hearing loss, gender, giddiness, and headache were found to be major risk factors.

Effect of Compression, Digital Noise Reduction and Directionality on Envelope Difference Index, Log-Likelihood Ratio and Perceived Quality.

The aim of the present study was to evaluate the use of the envelope difference index (EDI) and log-likelihood ratio (LLR) to quantify the independent and interactive effects of wide dynamic range compression, digital noise reduction and directionality, and to carry out self-rated quality measures. A recorded sentence embedded in speech spectrum noise at +5 dB signal to noise ratio was presented to a four channel digital hearing aid and the output was recorded with different combinations of algorithms at 30, 45 and 70 dB HL levels of presentation through a 2 cc coupler. EDI and LLR were obtained in comparison with the original signal using MATLAB software. In addition, thirty participants with normal hearing sensitivity rated the output on the loudness and clarity parameters of quality. The results revealed that the temporal changes happening at the output is independent of the number of algorithms activated together in a hearing aid. However, at a higher level of presentation, temporal cues are better preserved if all of these algorithms are deactivated. The spectral components speech tend to get affected by the presentation level. The results also indicate the importance of quality rating as this helps in considering whether the spectral and/or temporal deviations created in the hearing aid are desirable or not.

One-year prevalence and risk factors of tinnitus in older individuals with otological problems.

OBJECTIVE: The present study was carried out to estimate one year prevalence and risk factors of tinnitus in the older individuals (60 years and above) who reported with the ear and/or hearing related complaint to All India Institute of Speech and hearing, Mysore. METHODS: The case files of those who visited the institute during the above said period were reviewed retrospectively. RESULTS: The results of the study revealed that the prevalence of tinnitus was 16.81%. It was also found that 60.9% of the individuals with tinnitus were males. Further, 97.5% of the individuals with tinnitus had hearing loss. In addition, 28.53% of the individuals with tinnitus had moderate degree of hearing loss followed by moderately severe degree of hearing loss. Most of these individuals had sensorineural impairment. CONCLUSION: It can be concluded that prevalence of tinnitus is quite high in the older individuals with otological problems. The hearing loss, gender, giddiness, headache, hypertension, and diabetes were found to be major risk factors.