Lecture 5- Hearing Sensation

Question 1

hearing

Answer 1

nervous systems way of detecting the systematic movements of molecules through the air

Question 2

sound waves

Answer 2

caused when something vibrates, causing a systematic pattern in the movement of air molecules

Question 3

kinetic energy

Answer 3

transmitted through air molecules

Question 4

longitudinal waves

Answer 4

sound waves that travel through the medium of air or water

Question 5

transverse wave

Answer 5

propagating at right angles to the movement of molecules

Question 6

frequency of a sound wave

Answer 6

function of the rate of vibration of the object that is moving

Question 7

high pitched sounds

Answer 7

faster frequencies

Question 8

low pitch sounds

Answer 8

slower frequencies

Question 9

amplitude

Answer 9

function of changes in the amount of energy being propagated through the medium

Question 10

loudness

Answer 10

pressure; force with which the wave pushes into objects around it

Question 11

timbre

Answer 11

tone quality
- 2 sources create sound with same pitch and loudness, however they always sound different

Question 12

Pinna

Answer 12

attached to skull by ligaments and muscles.
-not well developed in humans, are in other animals
- bumps and ridges help focus and direct sound toward ear canal

Question 13

concha

Answer 13

deepest depression in pinna, leads directly to the ear canal, helps to focus and amplify sound waves

Question 14

ear canal

Answer 14

tube that runs from the outer to middle ear

Question 15

Tympanic membrane

Answer 15

eardrum

Question 16

ossicular chain

Answer 16

3 smallest bones in body, malleus, incus, stapes

Question 17

oval window

Answer 17

where the stapes attach to the inner ear. moves back and forth, causing fluids to shift back and forth

Question 18

bony labyrinth

Answer 18

consists of central chamber called vestibule, 3 semicircular canals, cochlea

Question 19

membranous labyrinth

Answer 19

inside bony labyrinth

Question 20

perilymph

Answer 20

liquid high in sodium (-) low in potassium (+)

Question 21

endolymph

Answer 21

low in Na, high in K+

Question 22

organ of corti

Answer 22

transduction begins

Question 23

place theory

Answer 23

differences in thickness of basilar membrane, shape of cochlea, nature of sound waves all allow different hair cells in cochlea to respond only to certain frequencies

Question 24

hair cells

Answer 24

1. don’t regrow once lost
2. wear out with age, starting with high-frequency receptive cells
3. can be damaged to long-term exposure to loud noise

Question 25

eustachian tube

Answer 25

canal that connects to the back of the nasal cavity and the throat
- controls air pressure in mid-ear, making it equal to the air pressure outside the body
- without it ear would burst outwards when air pressure dropped

Question 26

yawning, swallowing, chewing

Answer 26

opens up eustachian tube

Question 27

vestibulocochlear nerve

Answer 27

extends from the inner ear toward brain stem, transmits info related to sound and balance to central nervous system.
- consists of vestibular and cochlear nerves

Question 28

cochlear nerve

Answer 28

sound info

Question 29

vestibular nerve

Answer 29

balance info

Question 30

cochlear nuclear complex

Answer 30

where sound processing begins.
- consists of ventral cochlear nucleus (VCN)
- dorsal cochlear nucleus (DCN)

Question 31

ventral cochlear nucleus (VCN)

Answer 31

carries info related to the timing of neuron firing as well as the overall pattern of activation of auditory neurons (keep the beat)

Question 32

dorsal cochlear nucleus (DCN)

Answer 32

processing of spectral info and working out the direction of sound

Question 33

olivary nucleus

Answer 33

shaped like olives, involved in amplifying left/right difference between sounds

Question 34

directional hearing

Answer 34

sound comes from the left ear before the right ear, more intense in left, the source must be left

Question 35

lateral lemniscus

Answer 35

carries info from the brainstem to the midbrain, specifically the inferior colliculus

Question 36

inferior colliculus

Answer 36

where most ascending auditory neurons converge
- startle response
-vestibulo-ocular reflex

Question 37

medial geniculate body

Answer 37

in the thalamus- sends info to the cortex

Question 38

primary auditory cortex

Answer 38

where perception begins, bilateral damage results in cortical deafness, w ability to respond reflexively to sound (cant perceive, can sense)