Why are hair cells important?
Hair cells are the sound receptors in the hearing organ, the cochlea. Death of cochlear hair cells is the primary cause of sensorineural deafness. Hair cells die as we grow older. They can also be killed by exposure to loud noise, and by ototoxic agents (chemicals, including some valuable therapeutic drugs, which can damage the ear). Once lost, cochlear hair cells in humans are not replaced, so the hearing impairment is permanent. Similar hair cells in the vestibular (balance) organ, also located in the inner ear, play a key role in detecting head movements. When these cells are damaged, the resultant loss of balance control can contribute to severe motility problems. Loss of vestibular hair cells is the major underlying cause of falls in the elderly population.
