Binaural Dichotic Presentation of Speech Signal for Improving its Perception to Sensorineural Hearing-Impaired using Auditory Filters

Abstract

Sensorineural hearing loss relates to spread of spectral masking resulting in reduction in frequency resolving capacity. Such hearing-impaired persons find difficulties while identifying consonantal ‘place’ feature cued by spectral differences. In binaural dichotic presentation scheme splitting of speech signal in real-time into two signals with complementary short-time spectra using filters with magnitude response based on two auditory filter banks with linear phase was implemented and evaluated. Filter banks corresponding to eighteen critical bands over 5 kHz frequency range were used. Listening tests were performed on subjects with ‘mild73x2019; to ‘very severe’ bilateral sensorineural hearing loss. The usefulness of the scheme for better reception of spectral characteristics was evident as the results indicated improvement in speech quality, response time, recognition scores and transmission of ‘place’ feature particularly.