Parts of the Ear

  • Outer ear

    • Pinna- holds our glasses and acts as a partial funnel for sound to enter the ear canal.
  • Ear canal

    • Two parts cartilaginous and bony portion of ear canal
  • Middle ear

    • mechanical portion of the hearing mechanism that creates a three to one mechanical advantage to the sound waves entering the ear canal
      • Tympanic membrane- ear drum
      • Malleus – Hammer
      • Incus – Anvil
      • Stapes – Stirrup
  • Inner ear

    • Cochlea- snail shell shaped origin that is housed in the temporal bone of the skull.Contains inner and outer hair nerve cells that are tuned to different frequencies from high to low at the apical end of the cochlea. These hair cells serve to transport frequency specific electrical impulses to the brain for interpretation.
  • Retrocochlear

    • VIIIth cranial nerve carries the electrical impulses from the cochlea to the auditory pathways in the brainstem to the auditory cortex in the brain.
    • Auditory cortex receives the electrical impulses where they are interpreted as sound that is understood or identified as a new sound that needs to be interpreted.