Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

PSY280 > PSY280 - 9. Cutaneous Senses > Flashcards

PSY280 - 9. Cutaneous Senses Flashcards

(77 cards)

Start Studying
1
Q

somatosensation

A

umbrella term for sensory signals from the body.

3 major components: proprioception, kinesthesis + cutaneous senses

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

Ian Waterman: Loss of proprioception

A

forge new link between mind and body
planned movement - think it thoroughly
no movement is automatic - would have to be plotted
use of visualization - eyes have to tell mind what they were doing, control them
look at them to control them
other senses to tell brain what our body is doing

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

Proprioception

A

position of the body & limbs

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

Kinethesis

A

movement of body & limbs

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

The cutaneous senses

A

refers to touch, temperature & pain
tactile perception - most commonly think of in terms of touch
tactile: mechanical displacement of skin
touch is a near senses - have to be in direct contact
we have to act, not a passive sense

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Skin

A

heaviest & one of the largest organs in the body
varies over various parts of body
2 basic layers: epidermis (outer) +
dermis (inner) - connective + nutritive tissue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Skin

A

receptors within 2 layers

multiple channels of processing - diff receptors have diff functions: tell you about shape, temperature + texture

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Mechanoreceptors

A

tactile receptors - responsive to mechanical stimulation
each type of tactile receptor has an axon
each axon encapsulated - specialized nerve ending where transduction takes place
specialized endings give each type of tactile receptor their specialization

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Mechanoreceptors

A

Each type is characterized by:
kind of stimulation: pressure, vibration, movement - diff preference
size of RF: area of the skin where you touch affects firing rate of that perception

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

Mechanoreceptors

A

rate of adaptation: reduced firing in response to continuous stimulation, diff than habituation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Mechanoreceptors

A

slow adapting - response huge increase at onset, some decrement, but still see continuous firing for duration
fast adapting - spike at onset, rapid adaptation so total silence until the offset
slow adapting - prefer continuous
fast adapting - prefer change

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

Mechanoreceptors: SA1 Merkel - epidermis

A

sustained pressure, very low frequency (<5 Hz) spatial deformation, low vibration detection
slow adapting, continuously fire with presence, small RF
texture perception pattern/form detection

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Mechanoreceptors: RA1 Meissner - epidermis

A

temporal changes in skin deformation (~5-50 Hz), fast adapting - burst at onset + offset
detecting changes - slightly higher in frequency in changes across skin
low frequency vibration detectable - slipping heavy object
at start + end where most problematic
low frequency changes for both

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

Mechanoreceptors: SA2 Ruffini - dermis

A

sustained downward pressure, lateral skin stretch - tells us about form (grip), skin slip - eraser moving across skin
finger position, stable grasp, large RF
Ruffini cylinders - small encapsulation

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

Mechanoreceptors RA2 Pacinian - dermis

A

temporal changes in skin deformation (~50-700 Hz)
preference for change in high frequency vibrations + large RF = sensitive to small light changes
holding something in contact with something else - writing with 1 piece of paper on a desk

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

Kinesthetic

A

receptors help us determine where our limbs are & what movements they’re making:
muscle spindles: wrap around muscle fibres to detect length + shape + rate at which changing angle of limbs
either contracted + fat/long + slim which determines angle of limb

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Kinesthetic

A

receptors in tendons: muscle tension, muscle to bone

receptors on joints: active when joint is bent beyond normal limit - when it’s about to break

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

Thermoreceptors

A

Warmth fibers fire when skin temp of surrounding skin rises
Cold fibers fire in response to decreases in skin temp
both are free nerving - no specialized capsules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Thermoreceptors

A

37 degrees - neither cold/warm receptors fire that much
range is betw 10-50
colder than 17 and warmer than 47, properly retained by pain receptors
body keeps it at survivable temp

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

Nociceptors

A

free nerve endings

A-delta fibers respond to strong pressure or heat: myelinated (fast) - initial sharp pain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Nociceptors

A

C-fibers respond to intense stimulation of various sorts: unmyelinated (slow) - responsible for throbbing pain
pressure, heat, cold, chemicals
capsaicin - spicy - slow build

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Spinothalamic pathway

A

•evolutionarily older, slower, more synapses - slower because there’s more info exchange points
carries info from thermoreceptors & nociceptors
similar to Parvo + magno: concerned with diff kinds of info influences where they end up

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Medial lemniscal pathway

A

wider axons, fewer synapses, faster
tactile & kinesthetic information: pressure, vibrations, positional info
info necessary for execution of planned action sequences - so needs to be carried quickly to brain, important to get frequent feedback

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Medial lemniscal pathway

A

myelination within each, mostly in lemniscal
both go to spinal cord to maintain contralateral organization - happens earlier in Spinothalamic
both stop first at ventral posterior nucleus thalamus - up to cortex to S1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
cortex is somatotopically organized
spatial events on skin spatially mapped in somatosensory cortex need back + forth to be effective neurons in S1 + S2 have lots of crosstalk + with other cortical areas
26
cortex is somatotopically organized
S1 - original perceptual work S2 - more complex analysis generally areas of skin adjacent to each other are adjacantly organized in cortex
27
cortical magnification
Areas devoted to highly sensitive areas occupy more cortex in the brain than less sensitive areas somatosensory homunculus: hands, tongue, lips are huge
28
cortical magnification
good at tactile perception, more representation cortical magnification in vision: massive amount of space devoted to tiny fovea more space = more detail
29
two-point discrimination
threshold: minimum distance necessary to determine there are 2 separate stimuli poor discrimination - feels like 1 stimulus 75% or greater at the trial, distance is threshold
30
plasticity
Experience improves discrimination. | passive exposure - track 2 point discrimination on index finger - 1.1 mm
31
plasticity
passively experiences 2 points at varying distances threshold decreased to .9 mm without continued exposure, improvement disappears finger specific test left index, no diff
32
Are receptive fields getting larger or smaller?
Behavioral changes accompany changes in cortical organization: more cortex becomes dedicated to the finger tips cortical reorganization to represent long term improvement in discrimination correlated with expanded cortical representation for that area
33
Are receptive fields getting larger or smaller?
mapping out cortical area for each of 5 digits, map out specific area being trained 3 months training to pay attention to stimuli at tip area are dedicated to fingertip expanded + invaded into adjacent areas smaller: better for detail - HD - but need more
34
phantom limb
sensation perceived from physically amputated if nerve fibers are severed because limb is gone, experience of touch + pain has to be happening in brain touches to face and upper arm can be translated to senses of missing limb homunculus: area of cortex dedicated to missing limb, neurons are being coopted
35
phantom limb
areas that process face + upper arm start to invade, but not complete cortical reorganization based on experience can lead to somatosensory confusion - face processing starting to happen in that area rehab: mirrors to help resolve confusion
36
tactile acuity
Neurons in the somatosensory cortex have different sized receptive fields, depending on how important tactile sensitivity is for body part to function efficiently. stimulate area, anywhere on the large RF
37
tactile acuity: two point discrimination
track mean threshold as a function of body part hands + fingers, face: high acuity, low threshold calves to chest: high threshold feet: medium, low threshold, high acuity evolutionary in nature
38
tactile acuity: grating sensitivity
reflected in firing ability to detect orientation of grating merkel cells: response as function of grating as you pass stimulus over receptive field, stimuli correspond to activity in receptor
39
tactile acuity: grating sensitivity
preference for narrow bars with wide gaps small gaps are detectible, but not good representation, for detecting large detain Pacinian: continuous firing, not high frequency enough to detect changes
40
Haptic perception
knowledge derived from sensory receptors in skin, muscles, tendons & joints active info seeking: explore tactile stimuli to understand specific characteristics of stimuli
41
Haptic perception
inform object identification/material properties blindfolded: 100 common everyday objects accuracy near 100% around 2-3 seconds
42
Haptic perception
ppl engage in stereotypical set of hand movements to discover specific properties paired each procedure with types of info best at identifying Lateral motion: texture pressure: hard or soft
43
Haptic perception
static contact: temperature unsupported holding: weight enclosure: shape, volume contour following: global + exact shape, details
44
Pattern of firing
pattern of firing of different receptors code features specific shape represented by pattern of firing pattern mirrors curvature of balls larger: high activity at contact + decreasing activity as you move away from point
45
ventrolateral nucleus
processes kinesthetic information | similar to visual + auditory
46
ventral posterior nucleus
processes tactile information both much larger both first go to posterior but kinesthetic goes to ventrolateral MGN: centre surround organization to receptive field still fairly simple organization - ON/OFF signal
47
physiology of haptic perception: cortex
Neurons in cortex prefer simple features (orientation, direction of movement, shape). neurons progressively more complex organization S1: RF prefers horizontal align, silent for vertical orientation S2: tip of index finger, prefers upward motion - direction + movement
48
physiology of haptic perception: cortex
larger receptive field: entire palm: more active for flat shape of ruler, no change in response to cylinder ares of temporal cortex important for object identification: preference for shape
49
physiology of haptic perception: cortex
object identification is often multisensory in nature both receptor types in epidermis have small RF, in dermis have large RF thing detection - need to be in epidermis so not much penetration of skin is necessary
50
pain perception
can experience injury without experiencing pain can experience pain without stimulation realization where you start to feel pain phantom limb is opposite - no limb, but pain cortex is obviously involved in pain receptors
51
Pain
somewhat subjective with distinguishable components: sensory, cognitive, emotional separate components to whole experience
52
gate control model
t-cell - activity determines intensity of pain based on relative activity (transmission of pain to brain) activity dictated by s + l fibers - nociception S-fibers - nociception; increases t-cell activity - small, slow transmission, synapse with neurons that activate t cell that open pain gate
53
gate control model
L-fibers - non-painful tactile perception; large, can convey info fasterinhibits activity of t- cell
54
gate control model
SG- gate closes central control - cognitive influence on nociception model of pain perception through ganglion dorsal root to dorsal horn afferent (approaching) + efferent (existing)
55
gate control model
l-fibers:, inhibitory - decrease overall firing in t-cell that close the gate rubbing area to stimulate l-fibers get to interneuron first which will close the gate - overall perception of pain cognitive affects - top down - to influence perception
56
Attention
increase sensory-specific cortical activation attending to identity of object - increased activity in temporal attention increases neural response
57
Attention
somatosensory info - increase in activity that process V1: tactile attention condition: had to do something with condition - visual task in both cases experienced raised letters
58
Attention
virtual reality games to draw attention away from pain. how to treat burn patients - changing of bandages virtual reality games - snow world - immersive reality where they have snowball fight immersive nature of VR showed dramatic improvements, lower levels of pain
59
Placebo Effect
If you expect something to hurt, it will hurt more. experience of relief from symptoms resulting from a substance that has no pharmacological effect placebo influences expectations of pain
60
Placebo Effect
experience less pain when they don’t expect no pain not ethical to give placebos when they’re in real pain make analegesics more effective - by telling them you are giving them
61
Placebo Effect
giving them shot more effective than pills - assume that more effective in delivery + serious more pills, larger pills blue pills: soothing red pills: danger connotations
62
Co-occurring emotional
emotional experiences can modulate experience of pain fight or flight - processing pain less efficiently sympathetic - don’t have time to deal with pain in dangerous situation, pain is not helpful positive emotion make pain less painful
63
emotion & pain
Emotion can increase or decrease the experience of pain. images normed for valence lots of proportion of images that lots of people have rated normed according to intensity level
64
emotion & pain
high intensity not suitable to show - dead bodies + porn passively viewed images for international affective picture system cold pressor method: correlated with kind of images ppl viewed avg duration correlation with emotional valence
65
sensory component
sensory component: • thalamus • somatosensory cortices • insula
66
sensory component
sensory: describing type + intensity of pain burning, sharp, throbing - perceptual qualities insula: tucked in behind temporal lobe + parts of frontal lobe last place that dictates pain intensity
67
sensory component
affect/emotional processing: how unpleasant torturous, annoying - how we feel about it amygdala processes emotion cingulate: + orbito in particular orbito: modulates feelings for wide variety of stimulus
68
affective component
* thalamus * amygdala * anterior cingulate * prefrontal & orbitofrontal cortex
69
multimodal nature of pain
Suggestion can affect unpleasantness without affective intensity, indicating the two components are separable at the subjective level of experience. painful sitmulus: rate subjective pain intensity + unpleasant hypnotic suggestion: huge diff for unpleasantness: same
70
multimodal nature of pain
Increased unpleasantness ratings elicited changes in ACC, but not in S1, demonstrating the two components are separable in the brain. PET: low intensity suggestions accompany decrease in S1 lower unpleasantness suggestions accompany decrease in cingulate cingulate produce emotional response
71
Pleasant touch
separate component of | our experience of touch
72
Pleasant touch
Emotional properties of non-painful touch are mediated by C-tactile afferent fibers (CT afferents): •located in hairy skin •preference for slow-moving, lightly applied force
73
Pleasant touch
hairy skin: not purpose for manipulation development of emotional connection hormonal changes due to skin to skin contact slow moving lightly applied force - petting release of endorphins
74
Opioids
analgesics, reducing pain & inducing euphoria. endogenous analog was described. known power of opioids for a long time endogenous opioids: endorphins pitutitary gland in response to stress + painful stimulation + high intensity exercise + sex
75
Opioid receptors
binding site for opioids & endorphins Naloxone is a powerful opioid antagonist. prefered agent over both opioids like heroin or endorphins, but does nothing
76
Naloxone
``` can be used to treat opiate overdoses & can be used to identify conditions under which endorphins are released: • pain • placebo • pleasant touch • exercise • capsaicin ```
77
Naloxone
``` immediate effect - treat overdose pain - triggers endorphins - pain is more painful placebos less effective pleasant touch not nearly as pleasant exercise no longer euphoria capsaicin - myth ```

PSY280 (11 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions