Hearing loss is a decreased ability to hear.

The Anatomy of the Ear
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There are two main categories of hearing loss:

  • Conductive hearing loss is caused by something interfering with the sound passing to the inner ear
  • Sensorineural hearing loss is caused by damage to:
    • The cochlea—the major organ in the ear responsible for hearing
    • The 8th cranial nerve—the major nerve pathway and/or area of the brain responsible for hearing

Causes of conductive hearing loss may include:

Causes of sensorineural hearing loss is unknown in most people. Some causes may include:

  • Otosclerosis affecting the inner ear
  • Vascular disease that affects blood flow to the ear
  • Previous brain, ear surgery, or viral infection causing damage to the inner ear
  • Trauma