This proposal includes three new projects addressing the mechanical """"""""cochlear amplifiers"""""""" of the inner ears of vertebrates. The first project investigates the effects of various noxious agents on the responses to sound of the basilar membrane, the outer hair cells and auditory-nerve fibers at basal sites of the chinchilla cochlea. These agents have been chosen because they target the somatic electromotility of outer hair ceils (the putative amplifiers of mammalian cochleae) in vitro, affect otoacoustic emissions and/or otherwise affect outer hair cell function in-vivo or in-vitro. The second project will extend our recent findings on the development of passive cochlear traveling waves in newborn Mongolian gerbils by studying the maturation of the cochlear amplifier as reflected in the growth of basilar-membrane sensitivity and the strength of compressive nonlinearities. The third project consists of mechanical and electrophysiological recordings in the basilar papillae (analogues of the mammalian cochlea) of avian and reptilian species (pigeon, alligator and turtle), which have basilar membranes but not outer hair cells. The goal is to ascertain whether basilar-membrane vibrations in these species reflect the presence of stereociliar cochlear amplifiers which may play a role equivalent to that of outer hair cell somatic electromotility in mammalian cochleae. The results of the proposed research should be of fundamental value in defining the mechanical bases of auditory transduction in the inner ears of mammals and other vertebrates and may also serve to clarify the pathophysiology of sensorineural hearing loss in humans.

Agency
National Institute of Health (NIH)
Institute
National Institute on Deafness and Other Communication Disorders (NIDCD)
Type
Research Project (R01)
Project #
2R01DC000419-15A1
Application #
6580530
Study Section
Special Emphasis Panel (ZRG1-IFCN-6 (01))
Program Officer
Donahue, Amy
Project Start
1987-07-01
Project End
2007-11-30
Budget Start
2002-12-01
Budget End
2003-11-30
Support Year
15
Fiscal Year
2003
Total Cost
$520,499
Indirect Cost
Name
Northwestern University at Chicago
Department
Other Health Professions
Type
Schools of Arts and Sciences
DUNS #
160079455
City
Evanston
State
IL
Country
United States
Zip Code
60201
Charaziak, Karolina K; Siegel, Jonathan H; Shera, Christopher A (2018) Spectral Ripples in Round-Window Cochlear Microphonics: Evidence for Multiple Generation Mechanisms. J Assoc Res Otolaryngol 19:401-419
Temchin, Andrei N; Ruggero, Mario A (2014) Spatial irregularities of sensitivity along the organ of Corti of the cochlea. J Neurosci 34:11349-54
Recio-Spinoso, Alberto; Fan, Yun-Hui; Ruggero, Mario A (2011) Basilar-membrane responses to broadband noise modeled using linear filters with rational transfer functions. IEEE Trans Biomed Eng 58:1456-65
Temchin, Andrei N; Recio-Spinoso, Alberto; Ruggero, Mario A (2011) Timing of cochlear responses inferred from frequency-threshold tuning curves of auditory-nerve fibers. Hear Res 272:178-86
Temchin, Andrei N; Ruggero, Mario A (2010) Phase-locked responses to tones of chinchilla auditory nerve fibers: implications for apical cochlear mechanics. J Assoc Res Otolaryngol 11:297-318
Recio-Spinoso, Alberto; Narayan, Shyamla S; Ruggero, Mario A (2009) Basilar membrane responses to noise at a basal site of the chinchilla cochlea: quasi-linear filtering. J Assoc Res Otolaryngol 10:471-84
Ruggero, Mario A; Temchin, Andrei N (2007) Similarity of traveling-wave delays in the hearing organs of humans and other tetrapods. J Assoc Res Otolaryngol 8:153-66
Ruggero, Mario A; Temchin, Andrei N (2005) Unexceptional sharpness of frequency tuning in the human cochlea. Proc Natl Acad Sci U S A 102:18614-9
Recio-Spinoso, Alberto; Temchin, Andrei N; van Dijk, Pim et al. (2005) Wiener-kernel analysis of responses to noise of chinchilla auditory-nerve fibers. J Neurophysiol 93:3615-34
Temchin, Andrei N; Recio-Spinoso, Alberto; van Dijk, Pim et al. (2005) Wiener kernels of chinchilla auditory-nerve fibers: verification using responses to tones, clicks, and noise and comparison with basilar-membrane vibrations. J Neurophysiol 93:3635-48

Showing the most recent 10 out of 23 publications