7. HEARING Flashcards
(54 cards)
1
Q
- What is sound?
(in physics terms)
A
- a vibration that typically propagates as an audible wave of pressure
- this happens through a transmission medium
(such as: a gas, liquid or solid)
2
Q
- What happens when we talk?
A
- our vocal folds vibrate
3
Q
- What happens when we slap the top of a table or play guitar, what happens?
A
- the air particles vibrate
- this initiates sound waves
- these carry vibrations through the air
4
Q
- What do sounds generated from different mediums lead to?
A
- they lead to different sounds
- this is because different vibrating objects produce differently shaped sound waves
5
Q
- What is a sound frequency?
A
- it is the number of waves that pass a certain point at a given time
6
Q
- What is a high-pitched noise a result of?
A
- shorter waves that are moving in and out more quickly
7
Q
- What is a lower pitch a result of?
A
- slower fluctuations
8
Q
- What does the loudness of a sound depend on?
A
- it depends on the wave’s amplitude
- the amplitude is the difference between the high and the low pressures created in the air
- they are created in the air by sound waves
9
Q
- What is sound in the terms of human psychology and physiology?
A
- it is the reception of sound waves
- and the perception of these by the brain
10
Q
- Between which frequencies can human beings hear?
A
- between 20 Hz and 20 kHz
- everything under 20 Hz is infrasound
- everything over 20 kHz is ultrasound
11
Q
- What is the unit of measurement for the intensity of sound?
A
- decibels (dB)
12
Q
- How does the decibel scale work?
A
- it is logarithmic
- an increase of 10 decibels means that the sound is ten times louder
13
Q
- Sound above what decibel can cause hearing loss?
A
- any sound above 85dB
- hearing loss is related to both power of sound
AND length of exposure
14
Q
- Sounds above which decibel cause immediate damage and actual pain?
A
- sounds above 140 dB
15
Q
- What are the three parts that make up the human ear?
A
- outer ear
- middle ear
- inner ear
16
Q
- What does the outer ear consist of?
A
- the pinna
17
Q
- What is the function of the pinna?
A
- it protects the delicate inner parts of the ear
- it protects the external auditory meatus
(this is the air canal that collects sounds and directs it
towards the ear drum)
18
Q
- How is the shape of the pinna beneficial?
A
- it helps it to detect where sounds are coming from in the
vertical plane - this helps to identify whether sounds are coming from above or below the ear
19
Q
- What is the middle ear?
A
- it is an air filled cavity
20
Q
- Where is the middle ear located?
A
- it is located in the temporal area of the skull
21
Q
- What does the middle ear consist of?
A
- the ear drum
- the tympanic membrane
- the ossicles
- the eustachian tube
22
Q
- What shape is the tympanic membrane?
A
- it is concave
23
Q
- What is the tympanic membrane?
A
- it is an area between 60mm-90mm
- it has an average thickness of a 700s of a millimetre
- it has a very rich blood supply
24
Q
- What do the sound waves do to the tympanic membrane when they enter the ear canal?
A
- they strike the tympanic membrane
- they set it into motion
25
25. What determines how much the tympanic membrane will move?
- the loudness of the sound
- the louder the sound
- the more the tympanic membrane moves
26
26. What does the middle ear contain with regards to bone structure?
- it contains three small bones
- these are known as the ossicles
- they are connected in a chain across the middle ear
- they are connected from the tympanic membrane to the entrance of the cochlea
27
27. What is the biological term for the entrance of the cochlea?
- the oval window
28
28. What are the names of the ossicles?
- the malleus (hammer)
(the largest)
- the incus (anvil)
(the second largest)
- the stapes (stirrup)
(the smallest)
29
29. What does the tympanic membrane do in response to the sound?
- it vibrates
30
30. What happens in response to the vibration of the tympanic membrane?
- the ear drum moves the malleus
- this then moves the incus
- the stapes is then finally moved
- this then moves the foot plate in and out of the oval window
31
31. What is the result of the foot plate moving in and out of the oval window?
- there is an energy transfer
- this energy is transferred to the endolymph fluid in the cochlea
32
32. What are the two distinct portions of the inner ear?
- the vestibular portion
- the auditory portion
(the cochlea)
33
33. What is the focus of the vestibular portion?
- it is concerned with balance
34
34. What is the function of the auditory portion?
- it is concerned with hearing
35
35. What is the vestibular portion of the inner ear made up of?
- it is made up of three semicircular canals
36
36. What does each semicircular canal consist of?
- it has a swelling on the one end
- it has two membranous sacks
37
37. What is the biological name of the following:
37.1: the swelling of the semicircular canal
37.2: the two membranous sacks of the semicircular canal
37.1: the ampulla
37.2: the utricle
: the saccule
38
38. What do the utricle, the saccule and the ampulla all contain?
What is the function of these components?
- they contain fluid
- they contain sensory cells
- they move in response to the head movement
- they travel to indicate the body's status
39
39. With which organ and cells does the vestibular system work in conjunction (in connection) with?
What does the result in?
- the eyes
- the receptor cells in the joints of the body
- this continuously maintains our balance
40
40. What physical form does the cochlea appear in?
- it appears as a coiled tube
- it is in the shape of a snail shell
41
41. What is the cochlea wrapped around?
- it is wrapped around the acoustic portion of the auditory nerve
42
42. What is the cochlea split into?
- three distinct sections
43
43. Name the three distinct sections that the cochlea is split into?
- the scala vestibuli
- the scala media
- the scala tympani
44
44. What type of fluid do the scala vestibuli and the scala tympani contain?
- perilymph fluid
45
45. What type of fluid does the scala media contain?
- endolymph fluid
46
46. What separates the scala vestibuli from the scala media?
- the Reissner's Membrane
47
47. What separates the scala media from the scala tympani?
- the Basilar Membrane
48
48. What can be found along the basilar membrane?
- two types of sensory cells/hair cells
49
49. What are the two types of sensory/hair cells called?
- outer hair cells
- inner hair cells
50
50. How are these sensory/hair cells arranged along the basilar membrane?
- they are arranged in rows
- this is done according to their frequency
OR the pitch of sound they detect
51
51. What does each hair cell have?
What are these called?
- it has tiny hair like projections attached to it
- these are called stereocilia
52
52. What happens when sound energy is transferred to the cochlea?
- the basilar membrane vibrates up and down
- this causes the outer hair cells stereocilia to sheer
(SHEER: swerve, change course)
- they sheer on the tectorial membrane above them
53
53. What does the sheering action result in?
- it results in the stereocilia bending
- this opens the ion gates
- this leads to chemical changes
- it results in the electrical charge inside the cells
54
54. What do the electrical charges inside the cell do?
- they make neural impulses
- these travel along the auditory nerve to the brain
- this is interpreted as sound
