Hearing loss from intense noise exposure and ototoxic drugs greatly reduces the neural output of the cochlea. Despite a reduced cochlear output, neural activity in the central auditory pathway often becomes hyperactive at suprathreshold intensities indicative of Enhanced Central Gain. Enhanced Central Gain is believed to be responsible for hyperacusis, a condition in which listeners experience everyday sounds as unbearably loud or even painful. The goals of this project are: (1) Determine if Enhanced Central Gain is responsible for the temporal and spectral features of hyperacusis, (2) Determine how the acoustic environment (sound enrichment/deprivation) modulates hyperacusis/loudness growth and Central Gain and (3) Determine how serotonin and GABA agonists/antagonists affect hyperacusis and Central Gain. The proposed studies will increase our understanding of the neural mechanisms of hyperacusis and test the efficacy of pharmacological agents to treat hyperacusis.
Individuals with cochlear hearing loss suffer from hyperacusis (loudness intolerance), a condition thought to arise from increased neural gain in the central auditory pathway. A series of experiments is planned to: (1) determine if the time course and spectral features of increased Central Gain matches the time course and spectral properties of hyperacusis (2) determine how acoustic stimulation/deprivation affects hyperacusis, loudness growth and Central Gain and (3) assess the effects of serotonergic and GABAergic drugs on hyperacusis and Central Gain. The proposed studies will provide both clinical and basic science insights relevant to understanding and treating hyperacusis.
|Zhang, Jianhui; Sun, Hong; Salvi, Richard et al. (2018) Paraquat initially damages cochlear support cells leading to anoikis-like hair cell death. Hear Res 364:129-141|
|Sheppard, Adam; Liu, Xiaopeng; Ding, Dalian et al. (2018) Auditory central gain compensates for changes in cochlear output after prolonged low-level noise exposure. Neurosci Lett 687:183-188|
|Chen, Guang-Di (2018) Hidden cochlear impairments. J Otol 13:37-43|
|Baizer, Joan S; Wong, Keit Men; Salvi, Richard J et al. (2018) Species Differences in the Organization of the Ventral Cochlear Nucleus. Anat Rec (Hoboken) 301:862-886|
|Manohar, Senthilvelan; Spoth, Jaclyn; Radziwon, Kelly et al. (2017) Noise-induced hearing loss induces loudness intolerance in a rat Active Sound Avoidance Paradigm (ASAP). Hear Res 353:197-203|
|Sheppard, Adam M; Chen, Guang-Di; Manohar, Senthilvelan et al. (2017) Prolonged low-level noise-induced plasticity in the peripheral and central auditory system of rats. Neuroscience 359:159-171|
|Jiang, Chen; Luo, Bin; Manohar, Senthilvelan et al. (2017) Plastic changes along auditory pathway during salicylate-induced ototoxicity: Hyperactivity and CF shifts. Hear Res 347:28-40|
|Chen, Yu-Chen; Chen, Guang-Di; Auerbach, Benjamin D et al. (2017) Tinnitus and hyperacusis: Contributions of paraflocculus, reticular formation and stress. Hear Res 349:208-222|
|Seigel, G M; Manohar, S; Bai, Y Y et al. (2017) An immortalized microglial cell line (Mocha) derived from rat cochlea. Mol Cell Neurosci 85:202-210|
|Zhang, Celia; Sun, Wei; Li, Ji et al. (2017) Loss of sestrin 2 potentiates the early onset of age-related sensory cell degeneration in the cochlea. Neuroscience 361:179-191|
Showing the most recent 10 out of 13 publications