Audition Flashcards
Which sections of the are are fluid/air filled?
External and middle - air
internal - fluid
Sound waves are directed from the __ to the ___
pinna to typmanic membrane
How are vibrations transferred in the middle ear?
tympanic membran, mallaes,incus, stabes to oval window
What does the auditory tube connect
throat to middle ear
What does the outer bony labyrinth contain
Cochlear
What is the sensory organ for audition?
Cochlea
Transmission of sound waves through the ear
- Pinna directs sound waves to the external auditory canal
- Sound waves strike the tympanic membrane
- Malleus, incus, stapes
- oval window
- Fluid pressure waves of the perilymph of the cochlea scala vestibuli
- Fluid pressure waves are transfered from the scala vestibuli to the scala tympani and eventually to the round window
- Pressure waves are generated in the endolymph inside the cochlear duct
- Endolymph cause the basilar membrane to vibrate which moves the hair cells of the organ of Corti. Bending of hair cell stereocilia results in the production of receptor potentials and the ultimate generation of AP
The auditory pathway
AP are transmitted along the bestibulocochlear nerve (VIII) where they enter the cochlear nuclei of medulla oblongata here theyascend contra or ipsilaterally. They go into the superior olivary nucles of the pons to the inferior coliculus then to the medial geniculate nucleus of thalamus and terminate in the primary motor cortex
What is the most common cause of acquired hearing loss
Noise induced
Provide examples of 0db, 30db, 60, 90, 100, 115 and 140 and the max exposure
0-quietest noise you can hear
30-whisper
60-normal convo
90-lawnmower, shop tools, truck traffic (8hrs/day)
100-Chainsaw, snowmobile (2hrs/day)
115-sandblasting, loud rock concert (15mins/day)
140 gun muzzle blast, jet engine, brief exposure can cause pain and injury (need hearing protection)
What are the two types of auditory impairment?
Nerve deafness
Conduction of deafness
Nerve deafness
impairment of the cochlea or auditory nerve (sensorineaural deafness)
Permanent cond
Conduction deafness
Impairment of tympanic membrane or ossicles
blockage (flu/cold)
an the inner hair cells in the cochlea be fixed?
No