Date of Award
Master of Science
Health and Rehabilitation Sciences
Dr. Susan Scollie
Speech intelligibility and quality scores were evaluated across four different hearing aid settings that differed in the strength of directional microphone (DM), digital noise reduction (DNR), and level dependent speech enhancement (LDSE) features, in quiet and noise, and in low and high reverberation environments. Twenty-two listeners with bilateral sensorineural hearing loss and ten normal hearing listeners participated in our study. Results indicated that the directional microphone condition provided significant improvement for speech recognition in noise, at both levels of reverberation. Addition of SE and DNR processing to directional microphone had both beneficial and detrimental effects on speech perception and sound quality depending upon the strength of processing, type of environment, and noise condition. Specifically, SE and DNR features operating at maximum strength degraded speech intelligibility in the high reverberation environment. The same processing condition was, however, rated as having higher sound quality especially when the masker was stationary noise at 0 dB signal to noise ratio in low reverberation. Clinical implications of these results are discussed.
Keymanesh, Akram, "Perceptual Evaluation of Digital Signal Processing Strategies In a Modem Hearing Instrument Across Noisy and Reverberant Environments" (2011). Digitized Theses. 3624.