Perception of Temporal Fine Structure in Individuals with Normal Hearing Sensitivity: A Comparison of Different Measures

Abstract

Speech is a complex signal fundamentally decomposed by the auditory filters into corresponding narrowband signals, each of which can be considered as a slowly varying temporal envelope (ENV) superimposed upon a rapidly oscillating temporal fine structure (TFS). Both ENV and TFS are coded in the auditory nervous system in terms of time related changes in the neural firing. Encoding these cues is considered vital for speech perception, especially in the presence of background noise. The study explored the relation- ship between different measures of sensitivity to TFS (TFS-speech, Recovered envelope speech (RENV), and sensitivity to TFS using complex tones) and also explored how these different measures of TFS were related to performance on speech perception in noise (SPIN) testing using sentence stimuli on twenty young adults with normal hearing. The sentences were degraded using five schemes and TFS perception of complex tones were assessed using two schemes. The findings of the study showed no significant correlation of the different measures considered in the study, namely, the perception of TFS-speech, the perception of RENV-speech, and the perception TFS in complex tones with SPIN scores in the participants of the study. The results of the study show that, in a normal hearing young adult, speech perception in the presence of continuous noise is not related to their sensitivity to different measures of TFS perception.