Hair Cell Loss Causes Age-Related Hearing Loss, A Study Shows

A study in the Journal of Neuroscience found that presbycusis — age-related hearing loss — is caused by damage to hair cells in the inner ear that render sound vibrations as electrical signals transmitted to the brain by the auditory nerve, reports Gilmore Health News . The researchers examined 120 human inner ears via postmortem quantitative microscopic analysis of the cells and fibers. The results indicated that greater hair cell loss was associated with high-frequency cochlear regions versus low-frequency cochlear regions. Past animal studies suggested that presbycusis is caused by loss of structure in the stria vascularis. Also significant is the finding that hair cell loss in aging humans is worse than in animal models of presbycusis. "Our study upends the dogma about the major cause of age-related hearing loss," said Harvard Medical School's Pei-zhe Wu. "Documenting the dominant role of progressive hair cell loss in the hearing impairment of normal aging means that the millions who suffer from this condition could benefit from the hair cell regenerative therapies that are the focus of ongoing research across the world."