Objective speech intelligibility prediction in sensorineural hearing loss using acoustic simulations and perceptual speech quality measures

Abstract

A novel approach to objectively predict speech intelligibility in sensorineural hearing loss using acoustic simulations of impaired perception and objective measures of perceptual speech quality (PESQ) is proposed and validated. Acoustic simulations of impaired perception with different types and degrees of hearing loss were obtained degrading of the original speech waveforms by spectral smearing, expansive nonlinearity, and level scaling. The CUNY NST syllables were used as test material. PESQ was used to measure perceptual quality of the acoustic simulations thus obtained. Finally, PESQ scores were transformed into predicted intelligibility scores using a logistic function. Validation of the proposed objective method was performed by comparing predicted intelligibility scores with subjective measures of intelligibility of the degraded speech in a group of ten subjects. Predictive intelligibility scores showed good correlation (R² = 0.7) with subjective intelligibility scores and a low error in the prediction (RMSE = 0.14). The proposed approach could be a valuable aid in real clinical applications where it is needed to measure speech intelligibility and might be of some help in avoiding time-consuming experimental measurements. In particular, this method might be valuable in the characterization of the sensitivity of new speech tests for screening and diagnosing of hearing loss, or in the assessment of the performance of novel algorithms of speech enhancement for a target hearing impairment.