Ear Anatomy

Ear Anatomy

• Outer Ear (Pinna or Auricle)
  • Collects sound waves
  • Directs sound waves into the ear canal
  • Made of cartilage and skin
• Ear Canal (External Auditory Meatus)
  • Tube that connects the outer ear to the eardrum
  • Lined with wax-producing glands and hair follicles
  • Approximately 2.5 cm long
• Eardrum (Tympanic Membrane)
  • Thin, transparent membrane that separates the ear canal from the middle ear
  • Vibrates from sound waves, transmitting sound to the middle ear
• Middle Ear
  • Air-filled cavity containing three small bones (ossicles):
    • Malleus (hammer)
    • Incus (anvil)
    • Stapes (stirrup)
  • Ossicles amplify sound vibrations, transmitting them to the inner ear
• Inner Ear
  • Contains the cochlea and vestibular system
  • Responsible for sound processing and balance

Auditory System

• Sound Transmission
  • Sound waves enter the ear canal and strike the eardrum
  • Vibrations from the eardrum are transmitted through the ossicles to the inner ear
  • The cochlea converts vibrations into electrical signals
• Cochlea
  • Spiral-shaped structure in the inner ear
  • Divided into three fluid-filled compartments:
    • Scala vestibuli (perilymph)
    • Scala media (endolymph)
    • Scala tympani (perilymph)
  • Hair cells in the cochlea convert vibrations into electrical signals
• Auditory Nerve
  • Carries electrical signals from the cochlea to the brain
  • Interprets sound signals as sound
• Sound Processing
  • The brain processes sound information, including:
    • Pitch
    • Loudness
    • Location
    • Sound source identification

Ear Anatomy

• The outer ear (pinna or auricle) collects sound waves and directs them into the ear canal.
• The ear canal is a 2.5 cm long tube that connects the outer ear to the eardrum, lined with wax-producing glands and hair follicles.
• The eardrum is a thin, transparent membrane that separates the ear canal from the middle ear and vibrates from sound waves.
• The middle ear is an air-filled cavity containing three small bones (ossicles): malleus (hammer), incus (anvil), and stapes (stirrup) that amplify sound vibrations.
• The inner ear contains the cochlea and vestibular system, responsible for sound processing and balance.

Auditory System

• Sound transmission occurs when sound waves enter the ear canal, strike the eardrum, and vibrations are transmitted through the ossicles to the inner ear.
• The cochlea is a spiral-shaped structure in the inner ear, divided into three fluid-filled compartments: scala vestibuli (perilymph), scala media (endolymph), and scala tympani (perilymph).
• Hair cells in the cochlea convert vibrations into electrical signals.
• The auditory nerve carries electrical signals from the cochlea to the brain, interpreting sound signals as sound.
• Sound processing in the brain includes identifying pitch, loudness, location, and sound source.