Lecture 5 Flashcards
Three bones in middle ear
malleus
incus
stapes
what is attenuation reflex
helps protect ear against damaging sounds tensor tympani (attached to malleus) and stapedius muscle (Attached to stapes) --> pull stapes away from oval wind which dec vibrations sent to cochlea
scala vestibuli has perilymph true or false?
true
which window meets the scala media at the base of the cochlea
round window
which window meets the scala tympani at the base of the cochlea
oval window
which membrane separates scala vestibuli from scala media
reissner’s membrane
which membrane separates scala tympani from scala media
basilar membrane
scala media is high in perilymph, true or false
false- endolymph (high in K+)
where is helicotrema found?
Fn?
apex of cochlea
fn: connect scala vesitbuli to tympani and move fluid through
where is spinal ganglion of ear located?
modiolus
fn of outer hair cells
sharpen frequency response of cochlea
what is place code
basically, the position in basilar membrane determines strength of frequency…
close to base, higher frequency
closer to apex, lower frequency
what are tip links
connect the sterocilia together
what are tuning curves
response of auditory n fibers to different sound frequencies
what is characteristic frequency
frequency with LOWEST threshold for a response form auditory nerve
what does dorsal cochlear nuclei analyze
frequency and patterns of sound
what does ventral cochlear nucleus analyze
timing and directional source
what does superior olive nucleus analyze
timing and directional source
what do nuclei of lateral lemniscus analyze
monaural sound info: sound onset + sound duration
fn of auditory cortex
consciously perceive sound
which SO do sounds waves below 3 kHz go to
MSO
which SO do sounds waves above 3 kHz go to
LSO
coincidence detectors respond best when
signals from both ears arrive at the same time
(each ear might get sound input at a different time because of differences in axons length…so stimulus hitting ears at diff times but arriving to SO at same time)
via what is the contralateral LSO inhibited
medial nucleus of the trapezoid body (MNTB)
wernickes area is part of which auditory cortex
secondary auditory cortex
