The purpose of this project is to determine the nature of the hearing difficulties experienced by listeners whose ability to hear quiet sounds like pure tones is still relatively good. One particular focus of the project is on older listeners who, despte normal audiograms, find understanding speech in background sounds difficult. For comparison, younger listeners with cochlear hearing loss will also be examined. The framework of the project is structured around 3 Specific Aims.
The first Aim explores the possibility that normal thresholds in quiet can belie permanent neural dysfunction at the level of the auditory nerve, a situation that parallels noise exposure work showing that recovery of sensitivity following acoustic over-exposure can occur despite residual nerve damage.
This Aim will lead to a better delineation of the sound-processing deficits that exist in the face of apparently good hearing.
The second Aim focuses on auditory brainstem responses [ABRs] evoked by complex sounds like speech. This type of ABR testing is rapidly growing in usage but much remains to be understood about the basic response. The immediate goal of the second Aim is to study the particular situation of age-related differences in the speech-evoked ABR, but the broader objective is to use this study as a vehicle to better understand the multiplicity of factors that contribute to the generation of the speech-evoked ABR both in the normal and cochlear-impaired auditory system.
The final Aim contributes a new perspective on factors that affect speech understanding in everyday listening environments where the background sound is typically fluctuating in both time and frequency making the glimpses of target speech themselves dynamically vary across these dimensions as well as across ears. Together, these three Aims combine to provide a series of parallel studies that will significantly advance our understanding of the processing of complex sounds like speech in challenging listening environments, even for people with relatively good hearing.

Public Health Relevance

of this project to public health is that it advances our understanding of everyday listening difficulties experienced by people with hearing loss, as well as by people whose hearing is otherwise deemed to be good - especially those who are older. The project also provides new insights into objective tests of hearing that are gaining in popularity. Overall, the findings will be relevant to the public health challenge of the burgeoning communication difficulties experienced by an increasingly aging population.

National Institute of Health (NIH)
National Institute on Deafness and Other Communication Disorders (NIDCD)
Research Project (R01)
Project #
Application #
Study Section
Special Emphasis Panel (ZRG1-IFCN-B (03))
Program Officer
Donahue, Amy
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
University of North Carolina Chapel Hill
Schools of Medicine
Chapel Hill
United States
Zip Code
Grose, John H; Porter, Heather L; Buss, Emily et al. (2016) Cochlear hearing loss and the detection of sinusoidal versus random amplitude modulation. J Acoust Soc Am 140:EL184
Mamo, Sara K; Grose, John H; Buss, Emily (2016) Speech-evoked ABR: Effects of age and simulated neural temporal jitter. Hear Res 333:201-209
Grose, John H; Menezes, Denise C; Porter, Heather L et al. (2016) Masking Period Patterns and Forward Masking for Speech-Shaped Noise: Age-Related Effects. Ear Hear 37:48-54
Grose, John H; Porter, Heather L; Buss, Emily (2016) Aging and Spectro-Temporal Integration of Speech. Trends Hear 20:
Grose, John H; Griz, Silvana; PacĂ­fico, Fernando A et al. (2015) Modulation masking release using the Brazilian-Portuguese HINT: psychometric functions and the effect of speech time compression. Int J Audiol 54:274-81
Grose, John H; Mamo, Sara K; Buss, Emily et al. (2015) Temporal Processing Deficits in Middle Age. Am J Audiol 24:91-3
Grose, John H; Buss, Emily; Porter, Heather L et al. (2013) Across-frequency envelope correlation discrimination and masked signal detection. J Acoust Soc Am 134:1205-14
Grose, John H; Mamo, Sara K (2012) Frequency modulation detection as a measure of temporal processing: age-related monaural and binaural effects. Hear Res 294:49-54
Grose, John H; Mamo, Sara K (2012) Electrophysiological measurement of binaural beats: effects of primary tone frequency and observer age. Ear Hear 33:187-94
Grose, John H; Buss, Emily; Hall 3rd, Joseph W (2012) Binaural beat salience. Hear Res 285:40-5

Showing the most recent 10 out of 32 publications