Sound

Question 1

What you need for sound?

Answer 1

1. Pressurized sound wave

2. hair cells

Question 2

sound waves

Answer 2

pressurized air molecules with areas of high and low pressure

Question 3

pinna

Answer 3

outer part of the ear - you can see it. purpose is to funnel sound waves into auditory canal.

Question 4

tympanic membrane

Answer 4

eardrum

when sound waves hit it, it causes 3 little bones to vibrate - malleus, incus, stapes. These are attached to the oval window on the other side

Question 5

oval window

Answer 5

attached to the cochlea. When it vibrates, it causes the fluid inside the cochlea to move. It moves back again and hits the round window.

Question 6

cochlea

Answer 6

hair cells in the cochlea send an electrical impulse to your brain when they are moved by the vibrating fluid inside the cochlea.

Question 7

organ of corti

Answer 7

membrane in the middle of the cochlea. basically splits the cochlea in two

Question 8

external ear

Answer 8

pinna, auditory canal, and eardrum

Question 9

middle ear

Answer 9

mallus, incus, stapes

Question 10

inner ear

Answer 10

cochlea and semi-circular canals

Question 11

How does the fluid flow inside the cochlea lead to sound waves being processed?

Answer 11

Hair bundles are made of little filaments called kinocilium. Tip of each kinocilium is connected by a tip link. When fluid flows passed, it stretches the tip link, which opens up potassium channels to let potassium flow into the cell. Potassium channels then activate calcium channels to flow in. This causes an action potential in the spiral ganglion cell, which transmits a signal to the brain.

Question 12

how to differentiate between two different sounds?

Answer 12

cochlea distinguishes between sounds of varying frequency - this is known as auditory processing

Question 13

basilar tuning

Answer 13

cells at the base of cochlea are stimulated by high frequency sounds. cells at apex of cochlea (further in) are stimulated by low frequency sounds. The phenomenon of certain hair cells responding to only certain frequencies is known as basilar tuning.

Question 14

auditory processing

Answer 14

basically certain hair cells in the cochlea respond to certain frequencies. Those specific hair cells send an action potential to different areas of the brain, which is how you distinguish between different sounds. Primary Auditory Cortex receives the signals from the cochlea.

Question 15

tonotypical mapping

Answer 15

the brain’s ability to distinguish between different frequencies of sound