Case 4 - Audition Flashcards
1
Q
- What are some of the social consequences of hearing loss?
- What are some of the psychological consequences of hearing loss?
- What aspects of social exclusion do they suffer from?
A
- Social and behavioral difficulties, dependency, restricted opportunities
- Victims of abusive language, higher levels of stress, higher levels of mental health problems
- Social isolation, lack of education, and poverty
2
Q
- What is attention?
- What are the 3 elements of attention?
- What is alerting?
- What is orienting?
- What is selection?
A
- Selecting for active processing of specific aspects of your environment
- Alerting, orienting, and selection
- Change in internal state of individual in preparation for perceiving a stimulus
- Selection of information from sensory input i.e. moving towards the target etc.
- Choosing among multiple conflicting actions or responses
3
Q
- What are the 4 different types of attention?
- What is sustained attention?
- What is Selective attention?
- What is alternating attention?
- What is divided attention?
A
- Sustained attention, selective attention, alternating attention, divided attention
- Ability to keep focus for long periods of time even if exposed to repetitive actions or activity e.g. learning
- Selecting aspects when confronted with multiple stimuli
- Ability to switch or transfer focus from one activity to another
- Ability to focus on 2 or more stimuli simultaneously
4
Q
Define the following:
- Sound
- Frequency
- Hertz
- Pitch
- Intensity(Amplitude)
A
- Variations in air pressure which are audible
- Number of compressed pathces that pass by an object (ear) each second
- Number of cycles per second
- Tone - determined by the frequency
- Difference in pressure between compressed and rarefied patches of air. Determines loudness.
5
Q
- What is the range of sound humans can hear?
A
- 20Hz to 20,000Hz
6
Q
Identify the following:
- Pinna
- Auditory canal
- Ossicles (M,I,S)
- Oval window
- Cochlea
- Tympanic membrane
- Round window
- External acoustic meatus
- Helix
- Antihelix
- Auricular lobe
- Semicircular canals
- Eustachian tube
- CN VIII
- Where is each found?
A
Outer ear
- Pinna
- Auditory canal
Middle ear
- Ossicles (M,S,I)
Inner ear
- Oval window
- Cochlea
- Tympanic membrane
- Round window
7
Q
- What moves in the ear to start the process of audition?
- After the TM is moved what happens?
- What do the Ossicles do to sound waves?
- Which is larger the TM or the oval window?
A
- Tympanic membrane
- Ossicles vibrate, and move the oval window
- Amplify them
- Tympanic membrane
8
Q
- What is the attenuation reflex?
- Which muscles are involved?
- Why do we need the attenuation reflex?
- Is it instantaneous?
Identify:
- Stapedius muscle
- Tensor tympani muscle
A
- Muscle contraction in the middle ear, making the ossicles rigid.
- Tensor tympani & Stapedius muscles
- To protect the inner ear from damage
- No, takes time so damage can occur with fast and very loud sound
9
Q
- What is the function of the eustachian tube?
- How is it kept closed?
- What can be done to equalise middle ear pressure?
A
- To maintain the pressure in the middle ear, as it is continuous with the nasal cavities
- Valve
- Yawning or swallowing - opens the ET
10
Q
In the inner ear, identify:
- Oval window
- Round window
- Scala vestibuli - what does this contain?
- Scala media - what does this contain?
- Reissners membrane
- Basilar membrane
- Scala tympani - What does this contain?
- Helicotrema - what is this?
- Organ of Corti
- Tectorial membrane
- Stria Vascularis
- Spiral ganglion
A
Scala vestibuli & tympani - contain perilymph
Scala media - contains endolymph
Helicotrema - Where the scala tympani becomes continous with the scala vestibuli
11
Q
- What makes endolymph and periplymph different?
- What maintains the ionic content?
A
- Endolymph has a high K+ content
- Perilymph has a high Na+ content
- Stria vascularis
12
Q
- Where is the base of the basilar membrane?
- Which part of the basilar membrane is wider?
- Which part is more stiff?
- Movement of which fluid causes the BM to bend?
- High frequency waves cause what?
- Low frequency waves cause what?
- What does this establish for the brain?
Identify:
- Base of basilar membrane
- Apex of basilar membrane
A
- Base is closest to the oval window
- Apex
- Base
- Endolymph
- Base of the membrane vibrates a lot, dissipates energy
- Wave travels all the way to the apex, before energy dissipated
- Tonotopy - place code
13
Q
In the organ of corti, identify:
- Outer hair cells
- Inner hair cells
- Rods of corti - what is their function?
- Supporting cells
- Spiral ganglion
- CN VIII
A
Rods of corti - provide structural support
14
Q
- What happens in the organ of corti?
- What do hair cells do?
- What are hair cells (Type of cell)?
- How is sound transduced?
A
- Where auditory receptor cells (Hair cells) are found
- Convert mechanical energy into change in membrane potential
- Specialised epithelial cells
- Bending of hair stereocilia leads to sound transduction
15
Q
On the hair cells, identify:
- Stereocilia
1. What differentiates inner hair cells from outer hair cells?
A
- IHC - stereocilia are just below the tectorial membrane
- OHC - stereocilia are within the tectorial membrane
16
Q
- What do the hair cells synapse with?
- What does CN VIII project to?
A
- Spiral ganglion
- Cochlear nuclei in Medulla (Brainstem)
17
Q
- Movement of which membrane is necessary for transduction?
- What is found on the tip of the hair cells?
- Which position makes it generate a hair receptor potential?
A
- Basilar membrane
- Specialised ion channel, which opens and closes by bending of sterocilia
- Ion channel is open
18
Q
- What does movement of the tip link lead to?
- What ion moves into the cell?
- What does this lead to?
- What NT is released? To what cell?
A
- Increased tension, and rate of channel openings
- K+ (Depolarisation)
- Activation of Ca+ voltage gated channels - entry of Ca+
- Glutamate - to the spiral ganglion cells
19
Q
- When the movement of the tip link is in the opposite direction?
- What does this lead to?
- What happens to the ions?
- What kind of channel is the tip link channel?
A
- Relieves tension on tip link
- Channels spend more time closed
- Reduced inward movement of K+
- Mechanically gated (Physically opened)
20
Q
- How many hair cells does a spiral ganglion synapse with? (Inner and outer)
- How do OHC’s amplify sounds?
- What are the 2 motor proteins?
A
- Inner - 1 hair cell, Outer - Numerous
- Motor proteins change length of the hair cells to amplify the movement of the basilar membrane
- Prestin & Myosin
21
Q
- Where do the afferents from the spiral ganglion go?
- Which nuclei do they go to? On which side?
A
- Via CN VIII to the medulla
- Ipsilateral cochlear nuclei (Dorsal & Ventral)
22
Q
- Where do the axons from the ventral cochlear nucleus go to?
- Where do the olivary nuclei axons go?
- Where is the inferior colliculus?
A
- Superior olivary nucleus bilaterally
- via Lateral leminiscus to the Inferior colliculus
- Midbrain
23
Q
- Where do the axons of the Dorsal cochlear nucleus go?
- Where does the inferior colliculus send axons to?
- Where is this found?
A
- straight to the inferior colliculus of midbrain
- Medial geniculate nucleus
- Thalamus
24
Q
- Where does the MGN project to?
- What are the accessory projections?
A
- Auditory cortex (Temporal lobe)
- Superior colliculus & Cerebellum