An ongoing goal of our work has been to understand the effects of wide dynamic range compression (WDRC) amplification on temporal cues for speech recognition. WDRC is the default configuration in all digital aids, so the extent to which WDRC improves speech recognition dictates hearing aid benefit and use. However, WDRC can degrade the modulation properties of the signal, particularly the low-modulation rate (envelope) cues which are important for speech recognition. This project encompasses three sets of experiments that take a systematic approach to prescribing amplification parameters. The first specific aim is to define the extent to which envelope cues can be altered without degrading speech recognition. We will quantify how much envelope cues can be altered, particularly under conditions of spectral degradation similar to those experienced by listeners with hearing loss. We are most concerned with listeners with severe hearing loss who depend more on envelope cues, and who have received little attention in the literature. The second specific aim is to determine whether the acceptable level of envelope distortion depends on factors associated with degree of hearing impairment. The working hypothesis is that listeners who have reduced access to spectral cues, and therefore must rely more on envelope information, will have lower recognition scores due to the envelope alteration caused by WDRC. We will use several measures of ability to detect and use spectral differences necessary for speech recognition, which will be related to the speech-recognition changes due to envelope distortion. The third specific aim is to determine whether the acceptable amount of envelope distortion depends on the listening environment. We will consider the effect of two factors on the acceptable level of envelope distortion: effect of background noise and length of speech utterance. Ultimately, the goal of this work is to determine the range of compression values that maximize the restoration of audibility without distorting usable modulation cues.

Public Health Relevance

Hearing loss is one of our most pervasive health problems but the only treatment option for most of those with hearing loss is a hearing aid. To improve hearing aid satisfaction and benefit and avoid distorting important speech cues, we need to choose appropriate processing parameters for each individual. The focus of this project is to determine hearing aid settings that will provide the best possible speech recognition for each individual under a variety of listening conditions.

National Institute of Health (NIH)
National Institute on Deafness and Other Communication Disorders (NIDCD)
Research Project (R01)
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Auditory System Study Section (AUD)
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Donahue, Amy
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Northwestern University at Chicago
Other Health Professions
Schools of Arts and Sciences
United States
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Reinhart, Paul N; Souza, Pamela E (2018) Listener Factors Associated with Individual Susceptibility to Reverberation. J Am Acad Audiol 29:73-82
Reinhart, Paul N; Souza, Pamela E (2018) Effects of Varying Reverberation on Music Perception for Young Normal-Hearing and Old Hearing-Impaired Listeners. Trends Hear 22:2331216517750706
Souza, Pamela; Hoover, Eric; Blackburn, Michael et al. (2018) The Characteristics of Adults with Severe Hearing Loss. J Am Acad Audiol 29:764-779
Souza, Pamela; Wright, Richard; Gallun, Frederick et al. (2018) Reliability and Repeatability of the Speech Cue Profile. J Speech Lang Hear Res 61:2126-2137
Leonard, Stephanie A; Petito, Lucia C; Stephansson, Olof et al. (2017) Weight gain during pregnancy and the black-white disparity in preterm birth. Ann Epidemiol 27:323-328.e1
Headen, I; Cohen, A K; Mujahid, M et al. (2017) The accuracy of self-reported pregnancy-related weight: a systematic review. Obes Rev 18:350-369
Hoover, Eric C; Souza, Pamela E; Gallun, Frederick J (2017) Auditory and Cognitive Factors Associated with Speech-in-Noise Complaints following Mild Traumatic Brain Injury. J Am Acad Audiol 28:325-339
Ohlenforst, Barbara; Souza, Pamela E; MacDonald, Ewen N (2017) Response to Comment: RE: ) Exploring the Relationship Between Working Memory, Compressor Speed, and Background Noise Characteristics, Ear Hear 37, 137-143. Ear Hear 38:644-645
Reinhart, Paul N; Souza, Pamela E (2016) Intelligibility and Clarity of Reverberant Speech: Effects of Wide Dynamic Range Compression Release Time and Working Memory. J Speech Lang Hear Res 59:1543-1554
Shen, Jing; Wright, Richard; Souza, Pamela E (2016) On Older Listeners' Ability to Perceive Dynamic Pitch. J Speech Lang Hear Res 59:572-82

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