Effect of Nonlinear Frequency Compression on Frequency-Following Responses in Individuals with Sensorineural Hearing Loss

Abstract Objective The present study investigated the effect of nonlinear frequency compression (NLFC) feature of hearing aid on Frequency-Following Response (FFR) in individuals with sensorineural hearing loss (SNHL). Design : FFR responses were recorded with and without activation of NLFC of a hearing aid in individuals with Sensorineural hearing loss (SNHL). Additionally, FFR measures were compared between normal hearing individuals and individuals with sensorineural hearing loss using NLFC features. Study sample : Thirty-five adults aged 40–70 years with moderately severe to severe sensorineural hearing loss and 10 normal-hearing individuals were included in the study . Results No significant differences were observed in the latency & amplitude parameter of FFR measures in two test conditions, FFR recording with and without activation of NLFC feature in individuals with SNHL (p > 0.05). Further, comparison between normal-hearing individuals and individuals with SNHL revealed no significant differences in latency measures of FFR. However, amplitudes of F1 and F2 formants of FFR were found to be significantly reduced in participants with SNHL as compared to normal hearing individuals (p < 0.05) . Conclusion NLFC did not significantly influence FFR characteristics in individuals with SNHL. However, reduced harmonic encoding in the SNHL group suggests degraded neural representation of spectral speech cues at the brainstem level despite amplification.