auditory

Question 1

sound

Answer 1

audible variations in air pressure

Question 2

sound frequency

Answer 2

number of cycles per second expressed in units called hertz (Hz)

Question 3

cycle

Answer 3

distance between successive compressed patches

Question 4

human sound range

Answer 4

20-20,000 Hz

Question 5

high pitch =

Answer 5

high frequency

Question 6

which is louder, higher or lower intensity?

Answer 6

HIGHER

Question 7

stages of auditory pathway (in order)

Answer 7

• sound waves
• tympanic membrane
• ossicles
• oval window
• cochlear fluid
• sensory neuron response

Question 8

auditory pathway

Answer 8

• auditory receptors in cochlea
• brain stem neurons
• MGN in thalamus
• auditory cortex (A1)

Question 9

pressure is forced by

Answer 9

surface area

Question 10

how does fluid move?

Answer 10

when pressure at oval window is GREATER than tympanic membrane

Question 11

attenuation reflex

Answer 11

response where onset of loud sound causes tensor tympani and stapedius muscle contraction

Question 12

function of attenuation reflux

Answer 12

adapt ear to loud sounds, understand speech better

Question 13

perilymph

Answer 13

fluid in scala vestibuli and scala tympani

Question 14

endolymph

Answer 14

fluid in scala media

Question 15

endocohlear potential

Answer 15

endoplymph electric potential 80 mV MORE positive than perilymph

Question 16

physiology of cochlea

Answer 16

pressure at oval window pushes perilymph into scala vestibule, round window membrane bulges out

Question 17

structural properties of basilar membrane to sound

Answer 17

winder at apex, stiffness decreases from base to apex

Question 18

Georg von Bekesy research

Answer 18

endolymph movement bends basilar membrane near base, wave moves TOWARDS apex

Question 19

A.J Hundspeth research

Answer 19

basilar membrane upward, reticular lamina up and stereo cilia bends outward

Question 20

function of outer hair cells

Answer 20

sound transduction

Question 21

motor proteins

Answer 21

change length of outer hair cells

Question 22

prestin

Answer 22

required for outer hair cell movement

Question 23

characteristic frequency

Answer 23

frequency at which neurons is most responsive - from cochlea to cortex

Question 24

what type of neurons are present in the superior olive?

Answer 24

biaural neurons

Question 25

biaural neurons

Answer 25

receive information from both ears

Question 26

encoding information about sound intensity

Answer 26

- firing rate of neurons | - number of active neurons

Question 27

low frequencies

Answer 27

phase-locking on every cycle or some fraction of cycles

Question 28

high frequencies

Answer 28

NOT fixed

Question 29

interaural time delay

Answer 29

time taken for sound to reach from ear to ear (20-20,00 Hz)

Question 30

interaural intensity difference

Answer 30

sound at high frequency from one side of ear (2,000-20,000 Hz)

Question 31

mechanism of sound localization

Answer 31

- sound from left: activity in left cochlear nucleus sent to superior olive - sound reaches right ear, activity in right cochlear nucleus, first impulse far - impulses reach olivary neuron at the same time = summation = action potential;

Question 32

vertical sound localization

Answer 32

based on reflections from the pinnae

Question 33

primary auditory cortex

Answer 33

axons leaving MGN project to auditory cortex via internal capsule in array

Question 34

tonotopy

Answer 34

columnar organization of cells with similar binaural interaction

Question 35

lesion in auditory cortex

Answer 35

normal auditory function

Question 36

lesion in striate cortex

Answer 36

complete blindness in one visual hemifield

Question 37

different frequency band information

Answer 37

parallel procession, localization deficit

Question 38

frequency tuning

Answer 38

similar to characteristic frequency

Question 39

isofrequency bands

Answer 39

similar characteristic frequency, diversity among cells

Question 40

importance of vestibular system

Answer 40

balance, equilibrium, posture, head, body, and eye movement

Question 41

otolith organs

Answer 41

- gravity and tilt | - detect changes in head angle and linear acceleration

Question 42

semicircular canals

Answer 42

head rotation

Question 43

hair cells

Answer 43

used like auditory system to detect changes

Question 44

what cells respond to tilt?

Answer 44

macular hair cells

Question 45

push-pull activation of semicircular canals

Answer 45

- 3 on 1 side - help sense all possible head-rotation angles - each paired with another on opposite side of head

Question 46

vestibulo-ocular reflex (VOR)

Answer 46

- line of sight fixed on visual target | - senses rotations of head, commands compensatory movement of eyes in opposite directions

Question 47

auditory system

Answer 47

senses external movements

Question 48

vestibular system

Answer 48

senses movements of itself