somatosensory II Flashcards
fast pain receptor
mechanical and thermal nocioceptors
fast pain fiber type
small myelinated
fast pain tracts
neospinothalamic
fast pain thalamus
lateral VPL
fast pain function
sharp localized pain
slow pain receptor
polymodal nocioceptors
slow pain fiber type
unmyelinated
slow pain tracts
paleospinothalamic
spinoreticulothalamic
slow pain thalamus
medial thalamus
slow pain cortex
frontal and limbic
slow pain function
cortical arousal, affect
nociception proteases
breakdown kininogen to bradykinin
bradykinin bind to receptors that activate ion channels
heat over ___ opens heat sensitive ion channels on nociceptors
43
oxygen deprivation-
anaerobic metabolism release
lactic acid
–> high levels of H
polymodal
mechanical, thermal, chemical stimuli
capsaicin activates
TRPV1 receptor
trpv1 channels open at
lower temps
aspirin inhibits enzymes for ____ synthesis
prostaglandin
what fibers for pain and temp, some touch
A-delta(III)
small, thinly myelinated
what fibers for slow pain and temp
C(IV)
ascending pathways important for
position of body in space
arousal
anterolateral system or spinothalamic pathway
pain temp itch touch
pain fibers enter dorsal root enter zone ___
laterally
dorsal root entry zone also known as
zone of lissauer
second order neurons ascend contralaterally in the
medulla
pons
midbrain
second order neurons synapse in
thalamus
neospinothalamics synapse in
VP nucleus
spinoreticular tract is information
to the reticular nuclei which project to intralaminar nuclei of thalamus
important in arousal
spinomesencephalic tract information to
midbrain tectum
-coordinates eye and head movements
periaqueductal gray matter
-pain regulation
dorsal column medial lemniscus for
vibration, proprioception, fine touch
anteral lateral pathways for
pain, temp, crude touch
in spinal cord ALS and DC-ML pathways on what sides
opposite
ALS and DCML pathways come together in
caudal medulla
with hemisection of spinal cord patient loses
pain from opposite side of body about 2 levels below lesion
touch etc on same side
spinomesencephalic tract projects to
superior colliculus orienting to pain stimulus
periaqueductal gray-pain modulation
thalamus projects to
primary somatic sensory cortex
posterior thalamic nuclei
input
projects to
ALS
insular cortex
medial dorsal nucleus
input
projection
ALS
anterior cingulate cortex and orbitofrontal
thalamus plays role in
affecttive and motivational aspects of pain and in memory fo painful stimuli
cortex for painful stimuli
insular cortex and anterior cingulate
cortical projections from layers 5/6 project to
and modulate…
thalamus
brainstem
spinal cord
modulate sensory info thats ascending
pain modulation from___ to ___
periaqueductal gray
nucleus raphe magnus
neurons in raphe magnus project to
excite..
spinal cord
excite interneurons
-enkephalinergic
-inhibits 1st and 2nd order pain neurons
neurons in locus cereleus are
noradrenergic
