Perception of Sentences in Noise Using Different Number of Channels in Simulated Cochlear Implant Listeners

Abstract

Introduction: Previous literature reported increase in speech perception with increase in number of electrodes among individuals with cochlear implant.Objective: The objective of the study is to focus on the perception of sentences using different number of channels and signal to noise ratios (SNRs) in simulated cochlear implant listeners.Methods: The study comprised of thirty adults with normal hearing. Angelsim program was used to frame 4 sentence list which comprised of 40 sentences at +5.0 and -5dB SNR across different channels (4,8 and 32 channel). The recorded stimuli was presented in free field condition in which the situation varied from more most adverse situation (4 channels, -5dBSNR) to least adverse listening situation (32 channels, +5dBSNR) through a computer and a CD player which was routed through speakers placed at 00 azimuth.Results: Statistical analysis was carried out in which repeated measures of ANOVA revealed that there is considerable main effect across various SNRs at 4, 8 and 32 channel. The Bonferroni multiple pairwise comparisons also showed that there is significant difference in the nature of perceiving sentences with different channels (4,8,32 channels) at +5 dB, 0dB and -5 dB SNR.Conclusion: The finding of the current investigation enlightens the importance of greater number of channels and higher signal to noise ratio for enhanced perception of sentence in the presence of noise in simulated condition.