Chapter 7: Other Sensory Systems Flashcards

1
Q

Pinna

A
  • outer ear
  • flesh and cartilage
  • helps locate sound by altering reflections of sound waves
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Auditory Canal

A

-sound waves pass through

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Tympanic Membrane

A
  • ear drum
  • middle ear
  • vibrates at same frequency as sound waves that strike it
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Oval window

A
  • membrane of inner ear
  • small bones increase pressure of waves on small oval window
  • more force = necessary to move viscous fluid
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Cochlea

A
  • has 3 long fluid filled tunnels (scala vestibuli, scala media, scala tympani)
  • stirrup makes oval window vibrate which moves the fluid inside the cochlea
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Hair cells

A
  • auditory receptors
  • inside cochlea
  • vibrations displace the hair cells that open ion channels in the membrane
  • hair cells excite the cells of the auditory nerve (8th cranial nerve)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Pitch Perception: Place Theory

A
  • each area along basilar membrane is tuned to a specific frequency
  • each frequency activates the hair cells at only one place along basilar membrane and neurons distinguish the frequency based on what neuron responds
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Pitch Perception: Frequency Theory

A
  • basilar membrane vibrates in synchrony with a sound which causes auditory nerve axon to produce action potentials at the same frequency
  • not valid due to refractory period of neuron
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Current Theory of Pitch Perception: Low Frequency Sounds (up to 100Hz)

A

-modification of place theory and frequency theory
LOW FREQUENCY SOUNDS: up to 100Hz
-basilar membrane vibrates in synchrony with sound waves (frequency theory)
-auditory nerve axons generate 1 axon potential per wave
-soft sound activates fewer neurons
-stronger sound activates more neurons
-frequency of impulses identifies pitch
-#of cells identifies loudness

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Current Theory of Pitch Perception: High Frequency Sounds (above 100Hz)

A
  • fire every 2nd, 3rd, or 4th etc later wave
  • only at peak of sound wave
  • action potentials are phase locked
  • can have multiple auditory neurons that fire but not at the same time therefore take the sum of the neurons
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Volley Principle

A

-auditory nerve as a whole produces volleys of impulses for sounds up to 4000 Hz even though there is no one specific axon that does that frequency

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Sound localization

A
  • determining direction and distance of a sound requires comparing responses of the 2 ears
  • difference in intensity between 2 ears
  • difference of time of arrival
  • low frequency: phase difference, at different angles sounds are out of phase
  • high frequency: loudness differences
  • localize most by time of onset
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

types of hearing loss and the conditions that can cause them.

A

-disease, infections, or tumorous bone growth prevent middle ear from transmitting sound waves to cochlea
=conductive deafness
=middle ear deafness
-damage to cochlea, hair cells, or auditory nerve
=nerve deafness
=inner ear deafness
-can be inherited or from a variety of disorders
-exposure to loud noises=long term damage to synapses and neurons of auditory system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Tinnitus

A
  • ringing in ear

- can be from nerve deafness

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Role of otoliths

A
  • calcium carbonate particles next to hair cells

- when head tilts in different directions otoliths push against different sets of hair cells and excite them

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Role of semi-circular canals

A
  • oriented in perpendicular plane filled with jelly substance
  • lined with hair cells
  • acceleration of head causes jelly to push against hair cells
  • action potentials initiated by cells of vestibular system travel through 8th cranial nerve to brainstem and cerebellum
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Action Potentials initiated by vestibular system go…

A

-action potentials initiated by cells of vestibular system travel through 8th cranial nerve to brainstem and cerebellum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Free nerve ending

A
  • unmyelinated or thinly myelinated axons
  • near base of hairs and elsewhere in skin
  • pain, warmth, cold
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Hair follicle receptors

A
  • hair covered skin

- movement of hairs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Meissner’s corpuscles

A
  • hairless areas
  • sudden displacement of skin
  • low frequency vibration (flutter)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Pacinian corpuscles

A
  • Both hairy and hairless skin
  • sudden displacement of skin
  • high frequency vibration
22
Q

Merkel’s disks

A
  • both hairy and hairless skin

- light touch

23
Q

Ruffini endings

A
  • both hairy and hairless skin

- stretch of skin

24
Q

Krause end bulbs

A
  • mostly or entirely hairless areas
  • may include genitals
  • uncertain what they respond to
25
Q

cortical processing of somatosensory information

A
  • information from touch receptors on head enter CNS through cranial nerves
  • information from below head goes through spinal nerves
  • info travels through spinal cord on well defined pathways to brain
  • separate axons/pathways for deep touch and light touch
  • nervous system codes differences in sensory sensations in terms of which cells are active
  • areas of somatosensory thalamus send impulses to different areas of primary somatosensory cortex in parietal lobe (2 strips respond mostly to touch on skin, 2 others respond to deep pressure and movement of joints and muscles)
  • damage impairs body perception
26
Q

roles of the various neurotransmitters in the production of pain

A
  • pain starts with bare nerve ending

- pain axons release 2 NTs in spinal cord

27
Q

NTs for mild pain

A

-glutamate

28
Q

NTs for strong pain

A
  • glutamate

- substance P

29
Q

Alleviation of pain

A
  • opioid mechanisms that respond to opiate drugs and similar chemicals
  • opiate receptors act by blocking release of substance P
  • endorphins produced by brain are body’s own opioids
  • morphine post surgery block dull slow pain
  • large diameter axons are unaffected by morphine (sharp pain)
  • cannabinoids also block some types of pain
30
Q

Roles of NTs in production of itch

A

1) histamines that dilate blood vessels produce itch sensation
2) contact with certain plants
- axons are spcific for itch types also respond to heat
- itch axons activate gastrin releasing peptide
- itch pathway is slow to respond

31
Q

Alleviation of itch sensation

A
  • scratching produces mild pain

- pain alleviates itch meaning itch is not a types of pain

32
Q

Labelled line principle (application to senses)

A
  • each receptor would respond to a limited range of stimuli

- meaning would depend on which neurons are active

33
Q

Across-fibre pattern principle (application to senses)

A
  • each receptor responds to a wider range of stimuli
  • response by given axon means little except in comparison to what other axons are doing
    ex) colour perception
  • nearly all perceptions depend on pattern across array of axons (auditory, taste, smell)
34
Q

mechanisms of the taste receptors

A
  • stimulation of taste bud receptors on tongue
  • different chemicals excite different receptors and produce different rhythms of action potentials
  • temporal pattern may be important
  • neuron responds to tastes with different patterns
  • patterns code for different taste experiences
35
Q

taste receptors

A
  • modified skin cells
  • have excitable membranes
  • release NTs into brain
36
Q

flavour

A

-flavour=combination of taste and smell, taste and smell axons converge in endopiriform cortex which influences food selection

37
Q

Salty receptor

A

-permits Na+ to cross membrane

38
Q

Sour receptor

A

-detects presence of acids

39
Q

Sweetness receptor and umami receptor

A
  • metabotropic synapse

- molecules bind and activate G-protein

40
Q

Bitter receptor

A
  • metabotropic synapse

- 25+ types of receptors

41
Q

Anterior 2/3 Taste nerve pathway

A

-anterior 2/3 receptors travel along chorda tympani (part of cranial nerve 7 (facial nerve)

42
Q

Posterior receptors and throat receptors pathway

A

-travel along 9th and 10th cranial nerves

43
Q

Taste pathway

A

-from NTS information goes to pons, lateral hypothalamus and somatosensory amygdala, ventral posterior thalamus, and somatosensory cortex and insula (primary taste cortex)

44
Q

Primary taste cortex

A

Insula

45
Q

describe the operation

A
  • response to chemicals that make contact with membranes inside the nose
  • olfactory cells line olfactory epithelium in rear of nasal passage
  • olfactory cell has no cillia
  • olfactory receptors located on cillia
  • metabotropic receptors that respond to an odorant molecules instead of NT
  • each chemical excites several types of receptors
  • most strongly excited receptor inhibits activity of other ones via process similar to lateral inhibition
46
Q

number of olfactory receptors

A

-humans have several hundred olfactory receptor proteins

47
Q

the implications of the numbers of receptors for coding olfactory information

A

-large number of types of olfactory receptors makes it possible to identify chemical precisely

48
Q

why do we have so many olfactory receptors?

A

-olfaction processes airborne chemicals that do not range along a single continuum like wavelength

49
Q

types of stimuli that the vomeronasal organ responds to and differences between the vomeronasal and olfactory systems

A
  • sets of receptors close to olfactory receptors that respond only to pheromones
  • each VNO receptor responds to 1 pheromone
  • VNO receptor continually responds strongly even after prolonged stimulation (contrary to olfactory receptors)
  • alter autonomic responses
    ex) skin temperature
50
Q

Pheromones

A

-chemicals released by an animal that affect behaviour of other members of same species

51
Q

describe synesthesia and its possible anatomical basis

A
  • experience some people have in which stimulation of one sense evokes a perception of that sense and also another on
    ex) smelling colours
  • people who experience synesthesia have increased gray matter in certain brain areas and altered connections to other areas
  • possible genetic predisposition