EAR
Outer Ear Function Pinna External auditory meatus (canal) Ceruminous glands Tympanic membrane Eardrum
Middle Ear Auditory = Eustachian tube Ossicles Oval window Malleus Incus Stapes Oval window Round window
Inner Ear Osseous labyrinth filled with perilymph Membranous labyrinth filled with endolymph
Inner Ear Vestibule Utricle Saccule
Inner Ear Semicircular canals Semicircular ducts
Inner Ear Cochlea Vestibular Membrane Basilar membrane Cochlear duct (endolymph)
Inner Ear - Cochlea Scala tympani Scala vestibuli Spiral Organ = Organ of Corti Receptors for hearing are hair cells on the basilar membrane in the Spiral Organ
Hearing Sound transmission High frequency at base of cochlea Tympanic Reflex High frequency at base of cochlea Low frequency at apex of cochlea
Hearing Auditory pathway
Hearing Pitch determination (20-20,000 cps)
Hearing Loudness 1-120 db
Hearing Localization of sound Time reaching ear and loudness for both ears
Equilibrium Utricle and Saccule Macula = receptor Otolith Linear Acceleration Linear Deceleration Head Position
Equilibrium Semicircular ducts with ampulla- widened part Crista – hair cells Cupula = endolymph Rotational acceleration Rotational deceleration Vestibular nystagmus
Equilibrium Dynamic whole body equilibrium