Lecture 3 Flashcards
1
Q
what is the pathway: pain relevant loci (pain below the neck)
A
-skin/muscle/joint/viscera(“periphery”)
-dorsal root ganglion aka the DRG
-dorsal horn of the spinal cord
-brain
2
Q
what is the ascending pathaway aka the pain matrix like the pathway
A
-thalamus
-somatosensory cortex
-limbic cortex
-prefrontal cortex
3
Q
what is the descending pathways that is not motor
A
-hypothalamus
-midbrain
-brainstem
-spinal cord
4
Q
why do we have a descending pathways
A
because the brain wants to have control on which info it gets
5
Q
true or false: sensory information goes ventrally and motor information goes dorsally
A
false
sensory info goes dorsally and motor info goes ventrally
6
Q
meissner corpuscule
A
touch
7
Q
merkel discs
A
touch
8
Q
pacinian
A
vibration
9
Q
ruffini
A
stretch
10
Q
what is a nocireceptor
A
specialized neuron where pain starts
11
Q
true or false: nociceptors are multipolar
A
false:
they are unipolar basically one long axons with dendrites on both extremities with the cell body on the side
12
Q
what doies afferent mean
A
goes up from periphery to cns
13
Q
what does efferent mean
A
from cns to periphery aka controls muscles
14
Q
wht do a fibers conduct faster than C fibers
A
-because they are bigger
-myealated
15
Q
Aa axon type
A
-function: proprioception aka muscle control
-diameter 12-20 um
-speed: 80-120 m/s
16
Q
Ab axon type
A
-function: touch, vibration
-diameter 6-12 um
-speed: 35-75 m/s
17
Q
Agamma axn type
A
-function: thermal and pain
-diameter 1-5 um
-speed: 5-35 m/s
18
Q
C axon type
A
-function: pain and sweating
non-myalated
-diameter 0.2-1.5 um
-speed: 0.5-2.0 m/s
19
Q
why sometimes we feel a first pain and a second pain
A
because the agamma axons are faster than the C fibers
20
Q
true or false: nerve bundles need blood supply to curvive
A
true
21
Q
true or false: the efferent fibers that are coming out of T2 are controlling the muscles in T 2
A
trueeeeeee
22
Q
what does rostral mean
A
front of headf
23
Q
what does caudal mean
A
tail of head
24
Q
on the head what is dorsal
A
the top
25
on the head what does ventral mean
the bottom
26
what does medial mean
towards midline
27
hat does lateral mean
to one side
28
what does ipsilateral mean
on the side of
29
what does contralateral mean
on the opposite side of
30
what isd in the ventral root
-efferent fibers and motor neurons
31
what is in the spinal nerve
both afferent and efferent fibers
32
what is in the dorsal root ganglion
a collection of neurons that is outside the cns
33
what is in the dorsal root
afferent fibers
34
what does the ventral part vs dorsal look like on the spinal cord
ventral is the thicc part and dorsal is the skinny part
35
true or false: neurons in different layers have different shapes and sizes
true
36
true or false C fibers are found in the nerves of the somatic sensory system
true
37
true or false information from pain will ascend contralaterally
true
38
what is the pathway from pain fibers in skin and deep tissues
-pain fibers
-primary afferent neuron
-dorsal root ganglion
-second order neuron
-to brain and brain stem
39
what are the 2 types of C fibers and what do thet do
-peptidergic aka CGRP+they all terminate in lamina 1 of the dorsal horn
-IB4+: they terminate in the inner lamina II
40
Modern molecular def of sensory neurons
* defined by single-cell RNA-sequencing (i.e., gene expression) of DRG cells
followed by principal components analysis (i.e., clustering)
NF= neurofilament heavy chain (Nefh)-expressing
NP = non-peptidergic
PEP = peptidergic
TH = tyrosine hydrolase-expressing
41
true or false: neurogenic inflammation can happen in afferent and eferent fibers
true
the C fibers that release peptides will re;ease stuff
42
hpw does neurogenic inflammation works
the C fibers that release peptides will re;ease stuff
-then plasmic extravation will happen so make the vessels mroe poermeable
-lead to artery dilation to release white blood cells
43
true or false: if there is pain the is probs injury
true
44
what is the goakl of spinal reflexes
top bypass the brain and to go through the spinal cord instead
45
what happens through the spinal reflexes
smth happens to the skin, goes through sensory neuron, goes through the DRG into the dorsal horn, then through the ventral horn ibnto the cell body of a motor neuron, into a motor neuron into the mucles
46
true or false: the higher you go into thje spinal cord, the more white matter there is
true
47
what are the names of the 2 spots that the sensory info goes in
-the dorsal column and the antero lateral colum also called the ventral column
-sensory info goes up into one of these 2 places and that is where the fibers of second order are and then they go through any of the 3 tracts
48
what are the names of the 3 tracts
-spinothalamic tract
-spinoreticular tract
-spinoparabrachial tract
49
spinothalamic tract
-for sensiory and pain
-spinal cord
-medulla
-pons
-midbrain
-thalamud
50
spinoreticular tract
-emotional pain
-spinal cord
-medulla
-pons
-midbrain aka the reticular formation
51
spinoparabrachial
we dunno what it does
-spinal cord
-medula
-pons
-parabrachial aka the reticular nucleus
52
what ios somatotopy
the p[rinciple by which the location of the info corresponds to the part of the body in whitch it came from or is going to
53
somatotopy for dorsal and antero lateral column
-dorsal:
info from the lowest part of the body is the most medial while info from the highest part of the body is the most lateral
-antero lateral:
info from the lowest part of the body is the most lateral while info from the highest part of the body is the most medial
54
trigeminal anat
the pain info from the neck up goes through the trigeminal ganglion, into the trigeminal spinal tract , through the thalamus into the coirtex
55
true or false: the pelvic nerve goes staright through the spinal cord
facts
56
info from most organs go thgough three nerves
true
-greated splanchnic nerve
-lumbar colonic nerbe
-hypogastric nerve
then into the paravertebral ganglia aka the DRG
57
where does the vagus nerve go through
the brain directly
58
what si the NTS aka the nucleus tractus solitarius important for
visceral sensation
59
afferent fiber termination somatic vs visceral
-Somatic:
-where the c fiber ends in the spinal cord
c fibers from somatic tissues terminate very specifically
-Visceral: terminate much more diffused/wide
60
somatic and visceral: stimuli
-somatic:
mechanical
thermal
inflammatiry
-Visceral
-iscaemia
distension
inflammatory
61
sonmatic and visceral: localisation
-somatic: precise
-visceral: poor, reffered to somatic structures
62
brain mapping techniques big ones:
-lesions
-stimulation and recirdings
-hemodynamic responses
63
lesions:
-natural ex: disease and trauma
-induces: TMS which is reversible and surgery
64
stimulations and recording:
-direct: electrodes and optical imaging
-indirect: eeg and MRG
65
hempdynamic responses:
most common
pet scan
spect
fMRI
66
true or false: oarts that are mroe active in the brain will have the most blood in because it needs oxigen
true
67
why is the pain matric kinda mid
because all of these partys are also active in the brain for otehr things
68
what is in the brain matrix
-cortical areas
-acc
-insula
-thalamus
-M1 and S1
-PFC
69
part of the brain most active with patients that have chronic pain
pfc
Th
Ic
70
parts of the brain in normal subjecvts most active when have pain
acc
ic
th
71
sensory discriminative vs motivational affective: explain the SD aspects
-localization of pain'-quality of pain
-intensity of pain aka hypnosyus
-more in SI
72
sensory discriminative vs motivational affective: explain the MAA aspects
-how pleasant or unpleasant of pian
-meaning of pain
-more in ACC
73
sensory discriminative vs motivational affective: what did the study show
that we have different tracts for pain that are different
74
in what can we split the pain matric in
-affective
-cognitive
-inferential
-descending modulation
-motivational
-somatosensory
-thalamus
75
descendiug pathways the two things
-midbrain->periaqueductal gray to rostroventral medula
-midbrain to locus coeruleus to DRG
76
what are the 2 theories for pain physiology and who proposed them
-specificity aka the neurons for pain will start firing after a certain noxious stimuli by Ed Perls
-the intensity theory: the neurons fire even of the stimulation id ninnocuous by Pat Wall and Ron Melzack
77
explain the gate control theroy
-sg neuron
-L is touch
s is agamma and Cs
78
which technique is used to record from primary afferent fibers
-microneurography
tyoe of eeg
79
the 3 major dorsal horn projection neuron types
-wide dynamic range: a beta, a delta and C into the spinal cord
-nociceptive specific: a delta and C
-low threshold mechanosensitive: a beta
80
why are low treshold mechanosensitive neurons called silent nociceptors
-after surgery aka inflammation or nerve damage, it causes a change and urns them into nociceptive receptors os you are feeling pain
81
electrophysiological recording of anterior cingulate cells
they are higher in the brain wna dthey found that when you squeeze a mouse in any spot it fill fire
82
what is the fancy name for pain in one place can inhi it in another
heterotopic noxious conditioning stimulation
83
true or false: people with chronic pain have more CPM
false: they have less
84
true or false: transcutaneous electrical nerve stimulation stimulates deep muscles
false
it stimulates a and b fibvers not agamma or c
hence shows that the gate theory works
85
changes after injury: injured vs uninjured fibers
-pain causes changes ibn the fibers that are nearby or that synse with that neuyron
86
true or false: when you have an injury, all the nerves will be injured
nope, only a portion of them will
87
what is in the sciatic nerve
-nerves from the foot to the back of the leg
88
what is sensitization
type of plasticity: change in neuronal fucntion where the same input provides a bigger output
89
what are the 2 types of sensitization
periphery and central
90
skin nerve preparation is similar to whyich type of experiment
microneurography
91
what does bradykinin cause
peripheral sensitization
92
who showed central sensitization and how
-Clifford Woolf
-showed with the flexor reflex that the opposite leg of the stimulus would also fire more frequantly and longer
93
how can peripheral and central sensitization be showed
by doing readings in 2 spots
94
what does peripheral sensitization look like pre and post
post both the periferal neurons and the central neurons fire more
95
what does central sensitization look like
only the central will fire more
96
what is a proof that there is central sensitization exists
-there is temporal summation aka windup
-if you put analgesic on the local area it will block the peripheral sensitization but the neurons will still fire more
-mirror pain aka if you have pain on somewhere you will likely have pain on the other side
97
what are the 2 types of hyperalgesia
-primary: caused by periferal sensitization
-secondary sensitization
98
wghat are the 2 types of secondary hyperalgesia
-stroking hyperalgesia which is closer to the fl;are
-punctate hyperalgesia which is next to the stroking hyperalgesia aka it has a bigger circle
99
by what is caused paresthesia ectotopic activity
on a low treshold neuron
100
by what is cause spontaneous pain
ectotopic activity on na nociceptor
101
by what is caused dysesthesia and spontaneous pain
ectotopic activity on a low treshold neuron and a sensitized central pathways
102
what are the 2 types of plasticity after an injury
functional
-structural
103
example of functional plasticity
-molecular aja translational modifications
-synaptic: pre/post synaptioc potentiation
-cellular: the receptive fields become bigger
-network: more meurons get activated
104
examples of structural plasticity:
-synaptic spined:" more synaptic connections are made
-connectivity: neurons get branched or debranches
-Cell number: there are more or less cells
