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Objective: Comparison of Air conduction (AC) and Bone conduction (BC) auditory brain stem response (ABR) latencies.
Materials and Methods: In this cross-sectional study, 34 (17 males, 17 females) normal-hearing young subjects tested with AC- and BC-ABR .Wave V latencies of both procedures were compared
Results: BC- wave V latency significantly prolonged about 0.5 ms. That prolongation was less with decreasing intensity. Females&apos AC-and BC - ABR latencies were less than males&apos.
Conclusion: AC- and BC- ABR appeared to be useful to determine sensory-neural acuity in children with atresia or difficult to test subjects specially newborns.

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Background and Aim: The auditory system changes by increasing age in both central and peripheral parts. The purpose of this study was to  investigate the effect of the increasing the stimulus rate on auditory brainstem response (ABR)  waves latency in old population with normal hearing.
Materials and Methods : In this cross-sectional study click ABR test performed on 20 young normal-hearing subject with mean age of 20.8 years old and 10 old normal-hearing subject with mean age of 66.4 years old. ABR results with different stimulus rates were compared between two group.
Results : ABR peak latencies and interpeak intervals were prolonged with increasing the click repetition rate. Peak latencies were slightly prolonged in older adults and the I-V interval did not differ with age but prolongation of  III-V interval were significantly differs in older population compared to young adults.
Conclusion : Using high click rates may sensitize the ABR to the identification. of lesions of auditory nerve or brainstem , but before that , we need to know the normal range of different age groups , so that we can decide about probability of a retrocochlear lesion.

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Background and Aim: Tinnitus is an unpleasant sound which can cause some behavioral disorders. According to evidence the origin of tinnitus is not only in peripheral but also in central auditory system. So evaluation of central auditory system function is necessary. In this study Auditory brainstem responses (ABR) were compared in noise induced tinnitus and non-tinnitus control subjects.
Materials and Methods: This cross-sectional, descriptive and analytic study is conducted in 60 cases in two groups including of 30 noise induced tinnitus and 30 non-tinnitus control subjects. ABRs were recorded ipsilateraly and contralateraly and their latencies and amplitudes were analyzed.
Results: Mean interpeak latencies of III-V (p= 0.022), I-V (p=0.033) in ipsilatral electrode array and mean absolute latencies of IV (p=0.015) and V (p=0.048) in contralatral electrode array were significantly increased in noise induced tinnitus group relative to control group.
Conclusion: It can be concluded from that there are some decrease in neural transmission time in brainstem and there are some sign of involvement of medial nuclei in olivery complex in addition to lateral lemniscus.

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Background and Aim: The auditory steady state response is a modern test for estimating hearing thresholds, especially in difficult to test individuals . However, there are few bone conduction auditory steady state response data, particularly for individuals with hearing loss. The objective of this study was to investigate bone conduction auditory steady state response thresholds in individuals with sensorineural hearing loss and normal hearing.

Methods: In a cross-sectional study, 10 individuals with normal hearing and 10 with sensorineural hearing loss at the age of 15-30 years were selected by non-probability sampling. Auditory steady state response and pure tone audiometry to bone conduction stimuli in 500 and 2000 Hz were recorded in two groups. Paired and independent t-test were used to compare data between the groups.

Results: There was low correlation between bone conduction auditory steady state response and pure tone audiometry in both groups (p>0.05 for both). The difference of behavioral thresholds and auditory steady state response in 500 Hz was higher than 2000 Hz in both groups (p=0.033 for normal hearing and p=0.017 for sensorineural hearing loss groups). Comparison of these results showed significant differences between the two groups (p<0.001).

Conclusion: In both groups, there was low correlation between bone conduction auditory steady state response and pure tone audiometry thresholds. In individuals with sensorineural hearing loss and in higher frequencies , bone conduction auditory steady state response thresholds was closer to pure tone audiometery thresholds.