Search

Multi component tympanometry is not widely used in clinics due lack of evidence supporting its usefulness. The present study was undertaken to investigate the efficacy of multicomponent tympanometry for 1000 Hz probe tone in detecting middle ear pathology. Data were collected from 20 ears of 10 participants with no history of middle ear pathology (Group I) and 39 ears of 26 participants (Group II) with history of middle ear infection or ear-pain or blocking sensation. Single component tympanometry for 226 Hz probe tone and Susceptancec and Conductance tympanograms for 1000 Hz probe tone was carried out on all the participants. Results revealed normal tympanogram for both the probe tones for all the participants of Group I. It was observed that 53.84% of the ears could be identified as having middle ear pathology using 226 Hz probe tone whereas the percentage of correct identification increased to 94.87% when 1000 Hz probe tone was used. They are in accordance with the concept that subtle changes in the middle ear which cannot be detected by 226 Hz tympanogram can be identified using 1000 Hz multicomponent tympanogram. These findings highlight the efficiency of 1000 Hz probe tone in detecting mass dominant middle ear pathology.

Introduction: A review of literature on usefulness of Cortical Auditory Evoked Potentials (CAEPS) in verifying the usefulness of hearing aid shows equivocal results and a majority of the studies are carried out in a research laboratory. Objective: The aim of the present investigation was to investigate the usefulness of recording CAEPs for verification of hearing aids in a clinical set up. Material And Methods: CAEPs to stimulus /ma/, /ga/ and /ta/ were recorded from 14 persons with normal hearing and nine persons with mild to moderately severe sensorineural hearing loss. For persons with hearing impairment, the testing was carried out without a hearing aid (unaided) and with a hearing aid (aided) programmed based on NAL NL 1 prescriptive formula. Results: The results revealed that in aided condition, the detectability of CAEP responses was more when compared to unaided condition in persons with hearing impairment. There was a significant difference between the unaided CAEP responses of persons with hearing impair - ment and CAEP responses of persons with normal hearing. However, no such difference was observed between aided CAEPS responses of persons with hearing impairment and those of normal hearing. Conclusions: CAEPs can be reliably recorded in a clinical set up from individuals using hear- ing aids. The detectability of responses increases when a person is wearing hearing aid. CAEPs will be helpful in verification of hearing aids especially in persons with moderately severe to severe hearing loss.

OBJECTIVE: To investigate the effect of background noise on perception of unprocessed and envelope-enhanced speech in individuals with auditory neuropathy (AN). DESIGN: Open-set speech identification abilities were assessed for unprocessed and envelope-enhanced speech in quiet and at three signal to noise ratios (10, 5, and 0 dB signal to noise ratio) in 15 individuals with AN. RESULTS: Results revealed that speech identification ability was affected more in the presence of noise than in quiet. The participants were classified into two groups, Good Performers and Poor Performers, based on their speech identification scores in quiet. It was observed that the reduction in mean speech identification scores in noise was less for Good Performers when compared with that of Poor Performers. Envelope enhancement of the signal improved speech identification scores in both the groups. The analysis of results also showed that Good Performers showed a significant improvement in all the conditions, whereas Poor Performers showed improvement only in quiet and +10 dB signal to noise ratio. CONCLUSIONS: For individuals with AN, listening in background noise is more difficult than in quiet condition. Envelope enhancement of speech signal improves speech identification scores in quiet and in background noise for individuals with AN. However, the benefit obtained varies depending on the speech identification ability in quiet.

Individuals with auditory neuropathy (AN) often suffer from temporal processing deficits causing speech perception difficulties. In the present study an envelope enhancement scheme that incorporated envelope expansion was used to reduce the effects of temporal deficits. The study involved two experiments. In the first experiment, to simulate the effects of reduced temporal resolution, temporally smeared speech stimuli were presented to listeners with normal hearing. The results revealed that temporal smearing of the speech signal reduced identification scores. With the envelope enhancement of the speech signal prior to being temporally smeared, identification scores improved significantly compared to temporally smeared condition. The second experiment assessed speech perception in twelve individuals with AN, using unprocessed and envelope-enhanced speech signals. The results revealed improvement in speech identification scores for the majority of individuals with AN when the envelope of the speech signal was enhanced. However, envelope enhancement was not able to improve speech identification scores for individuals with AN who had very poor unprocessed speech scores. Overall, the results of the present study suggest that applying envelope enhancement strategies in hearing aids might provide some benefits to many individuals with AN.

Background Present study investigated the relationship between speech identification scores in quiet and parameters of cortical potentials (latency of P1, N1, and P2; and amplitude of N1/P2) in individuals with auditory neuropathy. Methods Ten individuals with auditory neuropathy (five males and five females) and ten individuals with normal hearing in the age range of 12 to 39 yr participated in the study. Speech identification ability was assessed for bi-syllabic words and cortical potentials were recorded for click stimuli. Results Results revealed that in individuals with auditory neuropathy, speech identification scores were significantly poorer than that of individuals with normal hearing. Individuals with auditory neuropathy were further classified into two groups, Good Performers and Poor Performers based on their speech identification scores. It was observed that the mean amplitude of N1/P2 of Poor Performers was significantly lower than that of Good Performers and those with normal hearing. There was no significant effect of group on the latency of the peaks. Speech identification scores showed a good correlation with the amplitude of cortical potentials (N1/P2 complex) but did not show a significant correlation with the latency of cortical potentials. Conclusion Results of the present study suggests that measuring the cortical potentials may offer a means for predicting perceptual skills in individuals with auditory neuropathy.

Objectives: To evaluate the effect of contralateral acoustic stimuli on speech identification scores and to correlate this effect to contralateral suppression of evoked otoacoustic emission. Design: Ten normal-hearing children with good academic performance participated in the study. Speech identification scores were measured in quiet and with different ipsilateral signal to noise ratios in two conditions, with and without contralateral acoustic stimuli. Transient evoked otoacoustic emissions were recorded for 70 dB SPL clicks with and without contralateral acoustic stimuli. Results: Findings revealed that contralateral acoustic stimuli enhanced speech perception when ipsilateral signal to noise ratios was +10 dB and +15 dB. This enhancement had significant positive correlation with contralateral suppression of OAE. Conclusions: The results of the present study support the hypothesis that medial olivocochlear bundle might aid in speech perception in noise, thereby suggesting a possible role of cochlear efferent fibers in hearing. The psychoacoustic measures can be used to evaluate the efferent auditory pathways, where it is not possible to record otoacoustic emissions.