The Senses: The Ear
The External Ear
Collects sound waves, channels them into ear canal
Rich in cartilage Continues to grow
throughout life!
Disorder: Cauliflower Ear
Trauma/Bruising leads to… accumulation of blood, tissue
Builds up between skin, cartilage
Tympanic membrane/Eardrum
Divides external and middle ear Vibrations of air cause this
membrane to vibrate, like a drum Diagnostic information
Redness, inflammation,Bulging = infection
External Auditory Meatus/Canal
Leads from auricle/pinna to tympanic membrane/eardrum
Collects sound waves Outer 1/3 contains:
Many short hairs Ceruminous glands – produce wax
(cerumen)▪ Collects debris▪ May accumulate, absorb/block sound waves
Middle Ear
Hollowed area of temporal bone (labrynth) Houses three very small bones (ossicles)
Malleus (hammer) Incus (anvil) Stapes (stirrup)
Transmits sound from tympanic membrane to oval window
Eustachian (auditory) tube – connects throat with middle ear – equalizes pressure
Condition: Otitis media
Blocked/inflamed Eustachian tube due to infection Can’t equalize pressure discomfort
Inner Ear Anatomy
Complex spaces in the temporal bone, called bony labyrinth Filled with watery perilymph Divided into:▪ Vestibule▪ Semicircular canals▪ Cochlea