Audition

Question 1

As you get older, your ability to process ____ frequencies ___

Answer 1

higher, deteriorates

Question 2

Frequency range for humans

Answer 2

20-20,000 hertz

Question 3

whales, dolphins, and dogs have a ____ frequency ranger than humans, while birds and frogs have a ____ range

Answer 3

wider, narrower

Question 4

Fish are on the ____ frequency extreme, while rodents and bats are on the ____ frequency extreme

Answer 4

low, high

Question 5

Amplitude

Answer 5

Louder, measured in decibels

Question 6

Frequency

Answer 6

Pitch (inversely related to amplitude/loudness), measured using hertz

Question 7

Purity

Answer 7

timbre

Question 8

External Ear

Answer 8

channels changes in air pressure to the middle ear - includes the pinna, auditory canal, and tympanic membrane

Question 9

Pinna

Answer 9

outer, curved part which collects sound waves to direct along the ear canal

Question 10

Auditory Canal

Answer 10

it narrows, amplifying the sound waves

Question 11

Tympanic Membrane

Answer 11

the eardrum; a thin membrane which vibrates with the sound waves, located at the end of the auditory canal

Question 12

Middle Ear

Answer 12

further amplifies for the inner ear - includes the ossicles

Question 13

Ossicles

Answer 13

attached to the inner ear - the hammer, anvil, and stirrup (or malleus, incus, and stapes), they hit the oval window

Question 14

Inner Ear

Answer 14

translates to changes in fluid pressure the converted into auditory neural impulses - inclues the oval window, the cochlea, the round window, and the basilar membrane

Question 15

Cochlea

Answer 15

a fluid filled tube (~35mm) that’s coiled like a snail, and contains the necessary neural tissues

Question 16

The Round Window

Answer 16

accommodates the liquid displaced by the vibrating of the oval window by bulging either in or out

Question 17

Basilar Membrane

Answer 17

runs the course of the cochlea – forced down by waves when the oval window is pushed in, pulled up when the oval window is pulled out (is also wider as you go down its length from base to apex)

Question 18

Low frequencies are received at the ____, and high frequencies are received at the ____

Answer 18

apex, base

Question 19

Auditory Receptors

Answer 19

also known as hair cells, they are part of the basilar membrane and are activated when it moves - two types, outer and inner

Question 20

Inner Hair Cells

Answer 20

less numerous, have 20 direct connections to the brain, send pitch information – axons that carry this information are thick and myelinated

Question 21

Outer Hair Cells

Answer 21

more numerous, share connections with 29 other hair cells (30 total per connection), amplify sound stimulus – axons that carry this info are thin and unmyelinated

Question 22

Auditory information is first sent to…

Answer 22

the cochlear nucleus in the hindbrain (medulla), then to separate dorsal and ventral streams

Question 23

Primary Auditory Cortex (A1)

Answer 23

located in the superior temporal gyrus of the temporal lobe, has tonotopic organization of sound waves with base neural impulses (high frequency) at one end and apex neural impulses (low frequency) at the other

Question 24

Interaural Time Difference

Answer 24

the difference of time for the sound to arrive at each ear (in milliseconds) - specific neurons in the superior olivary complex (pons) respond to this time difference (medial superior olive)

Other neurons respond to the difference in arrival times (in the dorsal cochlear nucleus)

Question 25

Interaural Intensity Difference

Answer 25

Loss of intensity between sounds received by each ear (the head casts a “sound shadow”) - for high frequencies - lateral superior olive

Question 26

Pinna Cues

Answer 26

differences in how the sound waves sound due to how they hit the folds of our pinna - necessary for elevation localization