Interventions and Future Therapies: Lessons from Animal Models
The chapters in this book provide ample evidence that age-related hearing loss is caused by multiple factors combining genetic traits with a constant barrage of lifetime insults to the hearing organ. Such insults may include noise exposure in occupational settings or at leisure (from loud machinery to iPods or rock concerts), chemicals and solvents in the work place, life style (drinking, smoking), diseases (diabetes, infections), and even the adverse “ototoxic” effects of medications on the inner ear. It is not even necessary that the insults be severe enough to cause immediate damage. Kujawa and Liberman (2006) subjected adult mice to a noise level that did not induce any threshold shifts two weeks after exposure. However, as the animals aged, they showed a continuing primary neural degeneration and deterioration of neural responses. Age-related changes in the central auditory system add to the complexity of the problem. Determining the cause(s) of hearing difficulties in an aging patient is challenging to say the least, let alone the question of how to prevent or treat such hearing impairment.
KeywordsHearing Loss Hair Cell Caloric Restriction Auditory System Inferior Colliculus
This work was supported by Grants R01 AG 07554 (to JFW) and P01 AG 025164 (to JS) from the National Institute on Aging, National Institutes of Health.
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