Prediction of Speech Perception with Recovered Envelope Cues from TFS stimulus For Normal Hearing Listener

Abstract

Speech perception refers to the understandability and ability of speech by a listener produced by a speaker. In order to interpret the speech information in the signal, human auditory system uses both envelope (ENV) and temporal fine structure (TFS) cues. While ENV is sufficient for understanding speech in quiet, TFS cues are necessary for speech segregation in noisy conditions. Speech cues can be classified into two categories; envelope (ENV) and temporal fine structure (TFS). In general, slow varying ENV (known as recovered ENV) can be recovered from the rapidly changing TFS; however, the degree of ENV recovery and its significance on speech perception are not clearly understood. In order to quantify the relative contribution of the recovered ENV for speech perception, this study proposes a new speech perception metric. The proposed metric employs a phenomenological model of the auditory periphery developed to simulate the responses of the auditory nerve fibers to both original and recovered ENV cues. The performance of the proposed metric was evaluated under different types of noise (both steady-state and fluctuating noise) at different sound presentation level. Finally, to validate the proposed metric, the predicted scores were compared with subjective evaluation scores from behavioral studies. The proposed metric indicates a statistically significant correlation for all cases and accounts for a wider dynamic range compared to the existing metrics.