Latency-intensity function of speech evoked auditory brainstem responses in individuals with moderate sensory neural hearing loss

Introduction: Compared to click evoked auditory brainstem response (ABR), speech evoked ABR holds an additional advantage by providing information on neural encoding of speech sounds. There is limited data available on speech ABR, both in normal and pathological ears. Aim: The present study focused on finding the latency-intensity function of speech evoked ABR in moderate sensorineural hearing loss (SNHL). Materials and Methods: Speech ABR was done using the standardized protocol on 13 ears with moderate SNHL were chosen from 20 participants. Results: Speech ABR recording on these ears produced V Peak till 60 dBnHL which was at the level of 10 dBSL. Results showed that the absolute latency of V Peak at the threshold level, that is, at 60 dBnHL was found to be 8.11 ms; 6.68 ms at 70 dBnHL; 5.96 ms at 80 dBnHL; and 5.41 ms at 90 dBnHL. Conclusion: It can be concluded that using speech as a stimulus in evoked responses, it can result in better estimation of loudness growth pattern in individuals with cochlear pathology. A phenomenon like recruitment can be explored in detail as it gives different results in comparison to click or tone evoked responses.