Hearing and Vestibular Senses

Question 1

sound

Answer 1

the sensation that we perceive when our tympanic membrane is stimulated by vibrating air molecules

Question 2

pressure waves

Answer 2

alternating cycles of compressed and rarified air

Question 3

amplitude

Answer 3

loudness

Question 4

threshold of hearing (TOH)

Answer 4

the sound level at which a noise is so quiet that a normal person can only hear 50% of the time

Question 5

frequency

Answer 5

pitch of a sound

Question 6

period

Answer 6

interval between sounds

Question 7

tympanic reflex

Answer 7

two muscles that can damp the vibrations of the middle ear in response to loud sounds to protect the ear form damage and adjust the gain of hearing

Question 8

ossicles

Answer 8

malleus + incus + stapes
transfer the force of the tympanic membrane’s vibration into vibrations of the membrane of the oval window, sending waves of vibration into the fluid that fills the cochlea

Question 9

round window

Answer 9

a ‘release valve’ for increases in cochlear fluid pressure that occurs when the oval window vibrates

Question 10

hair cells

Answer 10

the primary sensory neurons of the inner ear for both hearing and vestibular sensation

Question 11

stereocilia

Answer 11

hair-like protrusions on hair cells that transduce mechanical movements into nerve signals

Question 12

kinocilium

Answer 12

tallest hair cell

Question 13

tip links

Answer 13

tiny protein strands that join different stereocilia on each hair cell

Question 14

cochlea

Answer 14

a bony tube rolled up like a snail shell

scala vestibula + scala media + scala tympani

Question 15

organ of Corti

Answer 15

two rows of hair cells embedded in the base of supporting cells

Question 16

tectorial membrane

Answer 16

upper layer of the organ of Corti

Question 17

binaural input

Answer 17

input from both ears that helps the inferior colliculus to perform auditory localization by comparing the sound’s loudness and arrival time at one ear versus the other

Question 18

tectum of the midbrain

Answer 18

inferior and superior colliculi together

control orienting towards environmental stimuli

Question 19

medial geniculate nucleus (MGN)

Answer 19

auditory region of the thalamus that projects to the auditory cortex

Question 20

ampalla

Answer 20

bulbous enlargement at the base of the semicircular canal which contains an organ similar to the macula of the otolith

Question 21

vestibule-ocular reflex (VOR)

Answer 21

reflex keeps the eyes fixed on a target while the head moves around