Cochlear Synaptopathy and Noise-Induced Hidden Hearing Loss

Recent studies on animal models have shown that noise exposure that does not lead to permanent threshold shift (PTS) can cause considerable damage around the synapses between inner hair cells (IHCs) and type-I afferent auditory nerve fibers (ANFs). Disruption of these synapses not only disables the...

Full description

Saved in:
Bibliographic Details
Published inJournal of neural transplantation & plasticity Vol. 2016; no. 2016; pp. 1 - 9
Main Authors Liu, Lijie, Aiken, Steve, Li, Xiaowei, Chang, Ying, Shi, Lijuan, Wang, Jian
Format Journal Article
LanguageEnglish
Published Cairo, Egypt Hindawi Publishing Corporation 01.01.2016
John Wiley & Sons, Inc
Wiley
Subjects
Acoustic Stimulation - adverse effects
Animals
Cochlea - pathology
Cochlea - physiopathology
Hearing loss
Hearing Loss, Noise-Induced - etiology
Hearing Loss, Noise-Induced - pathology
Hearing Loss, Noise-Induced - physiopathology
Hearing protection
Humans
Noise
Noise - adverse effects
Noise control
Photoreceptors
Retina
Review
Sound
Synapses
Synapses - pathology
Synapses - physiology
Online AccessGet full text

Cover

More Information
Summary:Recent studies on animal models have shown that noise exposure that does not lead to permanent threshold shift (PTS) can cause considerable damage around the synapses between inner hair cells (IHCs) and type-I afferent auditory nerve fibers (ANFs). Disruption of these synapses not only disables the innervated ANFs but also results in the slow degeneration of spiral ganglion neurons if the synapses are not reestablished. Such a loss of ANFs should result in signal coding deficits, which are exacerbated by the bias of the damage toward synapses connecting low-spontaneous-rate (SR) ANFs, which are known to be vital for signal coding in noisy background. As there is no PTS, these functional deficits cannot be detected using routine audiological evaluations and may be unknown to subjects who have them. Such functional deficits in hearing without changes in sensitivity are generally called “noise-induced hidden hearing loss (NIHHL).” Here, we provide a brief review to address several critical issues related to NIHHL: (1) the mechanism of noise induced synaptic damage, (2) reversibility of the synaptic damage, (3) the functional deficits as the nature of NIHHL in animal studies, (4) evidence of NIHHL in human subjects, and (5) peripheral and central contribution of NIHHL.
Bibliography:ObjectType-Article-1
SourceType-Scholarly Journals-1
ObjectType-Feature-2
content type line 14
Academic Editor: Preston E. Garraghty
ISSN:2090-5904
0792-8483
1687-5443
DOI:10.1155/2016/6143164