The proposed program of research will increase our knowledge of cochlear function through a combination of theoretical and empirical studies addressing fundamental processes in ways that have both basic and translational implications. The program focuses on two interrelated areas: (1) the level-dependence of cochlear delays and (2) the effect on cochlear response growth at a particular frequency due to the presence of suppressors at other frequencies. Suppression and level-dependent latency share a common mechanism that is primarily responsible for cochlear compression. These areas represent features of normal cochlear function that are affected by cochlear hearing loss and potentially may be remediated by external hearing aids that incorporate sophisticated signal-processing strategies. The first two Aims of the proposal are to further understand (1) cochlear-reflectance generation and (2) the latency and masking of cochlear transients. Cochlear reflectance is defined as a transfer function between pressure waves entering and exiting the cochlea, and has advantages over other measures of cochlear responses. The remaining Aims are to determine the influence of (3) high-frequency suppression on cochlear distortion generators and (4) low- frequency suppression on cochlear compression. Through the work related to these four Aims, questions that possess both basic scientific interest and applied clinical relevance wil be answered by combined application of measurement and modeling efforts.

Public Health Relevance

The proposed research program will obtain measurements in human subjects and develop simulations with mathematical models related to (1) the travel time of transient sounds through the inner ear and (2) the interaction among frequency components of complex sounds. Comparisons between these measurements and simulations will address basic scientific questions and also will have clinical relevance in their potential to improve intervention strategies for hearing loss.

National Institute of Health (NIH)
National Institute on Deafness and Other Communication Disorders (NIDCD)
Research Project (R01)
Project #
Application #
Study Section
Auditory System Study Section (AUD)
Program Officer
Donahue, Amy
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
Father Flanagan's Boys' Home
Boys Town
United States
Zip Code
Rasetshwane, Daniel M; Fultz, Sara E; Kopun, Judy G et al. (2015) Reliability and clinical test performance of cochlear reflectance. Ear Hear 36:111-24
Souza, Natalie N; Dhar, Sumitrajit; Neely, Stephen T et al. (2014) Comparison of nine methods to estimate ear-canal stimulus levels. J Acoust Soc Am 136:1768-87
Rasetshwane, Daniel; Gorga, Michael; Neely, Stephen (2013) Signal-Processing Strategy for Restoration of Cross-Channel Suppression in Hearing-Impaired Listeners. IEEE Trans Biomed Eng :
Liu, Yi-Wen; Neely, Stephen T (2013) Suppression tuning of distortion-product otoacoustic emissions: results from cochlear mechanics simulation. J Acoust Soc Am 133:951-61
Rasetshwane, Daniel M; Neely, Stephen T; Kopun, Judy G et al. (2013) Relation of distortion-product otoacoustic emission input-output functions to loudness. J Acoust Soc Am 134:369-83
Neely, Stephen T; Stenfelt, Stefan; Schairer, Kim S (2013) Alternative ear-canal measures related to absorbance. Ear Hear 34 Suppl 1:72S-77S
Reuven, Michal L; Neely, Stephen T; Kopun, Judy G et al. (2013) Effect of calibration method on distortion-product otoacoustic emission measurements at and around 4 kHz. Ear Hear 34:779-88
Rasetshwane, Daniel M; Argenyi, Michael; Neely, Stephen T et al. (2013) Latency of tone-burst-evoked auditory brain stem responses and otoacoustic emissions: level, frequency, and rise-time effects. J Acoust Soc Am 133:2803-17
Rasetshwane, Daniel M; Neely, Stephen T; Allen, Jont B et al. (2012) Reflectance of acoustic horns and solution of the inverse problem. J Acoust Soc Am 131:1863-73
Rasetshwane, Daniel M; Neely, Stephen T (2011) Inverse solution of ear-canal area function from reflectance. J Acoust Soc Am 130:3873-81

Showing the most recent 10 out of 21 publications