By: Kaeleigh G, Julie B, Sami S, and Kyle S

Parts of the Ear  External (Outer) Ear: The auricle or pinna channels the sound and collects auditory waves.  Middle Ear (Tympanic Cavity): small mucous lined cavity within temporal bone.  Internal (Inner) Ear: bony chambers located deep within the temporal bone behind ear socket

External (Outer) Ear  Pinna - The “ear”. Shell shaped structure directing sound waves into the auditory canal  External Acoustic Meatus - Narrow chamber into the temporal bone of skull  Tympanic Membrane - Vibrates when the sound waves enter the auditory canal

Middle Ear  Tympanic Cavity - Small air-filled cavity in the temporal bone  Ossicles - Transmit vibratory motion of the eardrum to the fluids of the inner ear  Hammer & Anvil & Stirrup – Transmit the vibratory motion of the eardrum to the fluids of the inner ear Eardrum hammer anvil stirrup inner ear

Inner Ear  Cochlea - house the hearing receptors  Vestibule – oval cavity in the bony labyrinth  Semicircular Canals – balance organ in the ear

Sensory Receptors in the Ear  Sound vibrations move fluid which stimulates hearing receptors called mechanoreceptors. They respond to the physical force and allow us to hear a range of sound.

Trace the Pathway of a Sound Wave Through the Ear 1. Outside Stimulus 2. Pinna (External ear) 3. Auditory Canal 4. Eardrum 5. Hammer, Anvil, Stirrup 6. Cochlea 7. Mechanoreceptors 8. Auditory nerve 9. Brain

Types of Hearing Loss  Sensorineural Hearing Loss: Damage to the inner ear or cochlea, or to the nerve pathways from the inner ear to the brain. Illness Drugs Head trauma  Conductive Hearing Loss: Sound is not conducted efficiently from the outer canal to the eardrum. Ear infection Fluid in the inner ear