what is the function of hearing
what does language do
- Comprehension
what are the 3 structures that allow hearing to take part
what is the function of the central auditory nervous system
- Information processing
what is the outer ear divided into
Pinna
Ear Canal
what is the mode of operation of the outer ear
Air Vibration
what is the function of the outer ear
1) Protect ear
2) Localise
3) AMPLIFY
what is the middle ear divided into
Tympanic Membrane
Eustachian Tube
Small bones - stapes incus and malleus
what is the mode of operation of the middle ear
Mechanical Vibration
what is the function of the middle ear
1) IMPEDANCE MATCHING
2) Equalise pressure – Eustachian tube prevents a standing pressure difference on either side of the eardrum that would compromise function
3) Stimulate inner ear– the arrangement of ossicles transmits vibrational energy to the oval window, preventing it from being reflected away from the surface of the inner ear
what are the divisions of the inner ear
Cochlea
Semilunar canals
what is the mode of operation of the inner ear
Hydrodynamic (fluid)
Electrochemical
what is the function of the inner ear
1) Sound filtering
2) Signal Transduction
what is impedance matching
overcome the acoustic impedance between the air in outer ear and the fluid in the inner ear.
What are the two ways in which impedance matching is done
1) Transmission of Vibration through the Malleus, Incus and stapes, vibrations from transmitted ear to the bones causes a vibration ratio, so the malleus from the tympanic membrane moves 1mm the stapeus will move 1.3mm therefore there is a higher movement generated for fluid to move
2) Tympanic Membrane to Oval window area difference 22:1 this leads to Higher pressure generated over smaller area, these can overcome the high impedance of the cochlea and make the cochlear vibrate
what is between the middle ear to the outer ear
what part of the ear controls the transmission of sound
cochlear
what are the two parts of transmission of sound
- Amplitude Transmission ( Loud or Soft) - dB
describe how the cochlear transmits sound
what are the 3 canals in the cochlea
how is the 3 canals separated
what are the inner and outer hair cells attached to
describe the entire part of the cochlea
Entire organ: Organ of Corti
what is within the cochlear duct
Tectorial membrane