Effect of intensity on prevalence of N3 potential in ears with severe to profound hearing loss

Objective of the study: To look for the presence of N3 potential at two different intensities in children and in adults. Method: A total of 260 ears with severe to profound hearing loss were studied from the participants in the age range of 1 to 50 years, with 170 subjects in the age group below 10 years and remaining 90 subjects of more than 10 years. Auditory brainstem response (ABR) was recorded at two intensities, 90 and 99dBnHL, to look for the presence of N3 potential. Result: N3 potential was observed in 30% of the total ears taken in the study at 90dBnHL and 38.8% at 99dBnHL. Presence of N3 potential in children wass 45%, which wass higher than the age group of above 10 years. When the intensity was increased there was an increase in amplitude and a reduction in latency with better wave morphology. Conclusion: It is better to use higher intensity for the identification of the N3 potential while doing ABR and thus with the single recording, auditory assessment as well as saccular assessment can be done.