lect 9- Auditory Senses Flashcards Preview

PHYSIOLOGY SEMESTER 2 > lect 9- Auditory Senses > Flashcards

Flashcards in lect 9- Auditory Senses Deck (31):
1

describe the conduction pathway sequence (auditory)

tympanic membrane --> malleus --> incus --> stapes --> oval window

2

what does the malleus articulate with

the anvil (incus)

3

what does the malleus attach to

tympanic membrane

4

describe the incus (anvil)

intermediate bone between the stapes and the malleus; the name "incus" refers to an anvil, on which the hammer (malleus) strikes

5

what is the third bone in the series in the middle ear

stapes

6

what does the stapes insert onto

oval window

7

what does the oval window open into

scala vestibuli

8

where is the round window located

at the end of the scala tympani

9

what does the tensor tympani do

inserts on the malleus and pulls handle of malleus inward

10

what does the stapedius muscle do

inserts on the stapes and pulls stapes outward

11

when do the muscles of the middle ear contract

contract reflexively in response to loud sounds in order to dampen the vibrations of the auditory ossicles

12

what provides the impedance matching between the air and the fluid

the tympanic membrane and auditory ossicles

13

what are the major components of the cochlea

scala vestibuli, scala media, scala tympani and reissner's membrane

14

what separates scala medial from scala vestibuli

Reissner's membrane (vestibular membrane)

15

what does the basilar membrane separate

separates scala media from scala tympani

16

describe the basilar fibers

length increases from the oval window to the apex of the cochlea (helicotrema) and diameter of the fibers decrease from oval wind to the apex of the cochlea

17

what is the result of the different tights of fiber distribution in basilar fibers

still, short fibers near the oval window beat at a high frequency; long, limber fibers near the apex of the cochlea vibrate at a low frequency

18

what does the organ of corgi generate nerve impulses in response to

vibration of basilar membrane

19

what type of cells are the sensory receptors of the organ of corti

hair cells

20

what creates the rigid unit of the organ of corti

outer ends of hair cells are tightly attached to reticular lamina, supported by rods of corgi, which are attached to the basilar fibers.

21

what cranial nerve is involved with the organ of corti

CN 8: cochlear nerve

22

what does movement of the basilar fibers cause movement in

reticular lamina

23

what happens to hair cells when the basilar membrane moves

hair cells become excited

24

what is the scala media filled with

endolymph

25

what is the scala vestibule filled with

perilymph

26

what is the scala tympani filled with

perilymph

27

describe the concentrations of potassium and sodium in the endolymph

high concentrations of potassium and low concentration of sodium (perilymph is the opposite)

28

what is the different in mV between endolymph and perilymph and what is this called

called the endocochlear potential and is +80mV

29

what is the intracellular potentials of hair cells with respect to perilymph and endolymph

perilymph: -70mV
endolymph: -150 mV

30

define place principle

nervous system detects frequencies by determining positions along the basilar membrane that are most stimulated

31

list the components of the nervous system pathway (in order):

spiral organ of corgi, dorsal and ventral cochlea nuclei, superior olivary nucleus, lateral lamniscus nucleus, medial geniculate nucleus (thalamus), auditory cortex