Speech is an inherently dynamic signal and spectral dynamics are integral to perception of both consonants and vowels. The rate, direction, and extent of formant movements provide cues to consonant and vowel identity. The loss of peripheral auditory sensitivity, precise temporal processing, and frequency selectivity associated with hearing loss and aging will disrupt the perception of formant movements. As a result, the reduction or elimination of dynamic spectral cues may impair speech understanding, especially in adverse listening conditions such as background noise or reverberation. The purpose of this program of research is to understand the perception of dynamic acoustic signals by hearing-impaired listeners, with the long-term goal of improving speech understanding by these individuals, especially in adverse listening conditions. The proposed research compares the performance of normally-hearing and hearing-impaired listeners on a number of tasks designed to assess basic perceptual abilities in response to complex, non-speech auditory stimuli that change in frequency over time. Experimental procedures will consist of adaptive tests of spectral change detection and discrimination in non-speech stimuli which possess timing and frequency characteristics to those of speech, and estimation of spectral change detection and discrimination thresholds in several types of competing background noise and with simulated reverberation. Speech recognition ability in background noise and reverberation will also be assessed. Based on the results of these behavioral measures of spectral change perception and speech recognition, a computational model will be developed that can account for differences in speech intelligibility due to hearing status and stimulus characteristics. The effectiveness of the computational model will be evaluated by comparing model predictions with actual listener performance. The application of information regarding spectral change perception to a model of speech recognition will have implications for the development of new hearing aid processing strategies and rehabilitative auditory training programs that may enhance speech intelligibility and reduce listening effort in hearing-impaired individuals.

Public Health Relevance

Speech is an inherently dynamic signal and spectral dynamics are integral to perception of both consonants and vowels. The loss of peripheral auditory sensitivity, precise temporal processing, and frequency selectivity associated with hearing loss will disrupt the perception of spectral dynamics. The goal of this research is to understand the role of spectral dynamics in speech understanding with the expectation that this understanding will lead to better speech intelligibility assessment and communication rehabilitation.

Agency
National Institute of Health (NIH)
Institute
National Institute on Deafness and Other Communication Disorders (NIDCD)
Type
Research Project (R01)
Project #
1R01DC012314-01A1
Application #
8435764
Study Section
Language and Communication Study Section (LCOM)
Program Officer
Miller, Roger
Project Start
2013-03-01
Project End
2018-02-28
Budget Start
2013-03-01
Budget End
2014-02-28
Support Year
1
Fiscal Year
2013
Total Cost
$315,000
Indirect Cost
$65,000
Name
Oregon Health and Science University
Department
Otolaryngology
Type
Schools of Medicine
DUNS #
096997515
City
Portland
State
OR
Country
United States
Zip Code
97239
Molis, Michelle R; Kampel, Sean D; McMillan, Garnett P et al. (2015) Effects of hearing and aging on sentence-level time-gated word recognition. J Speech Lang Hear Res 58:481-96