Sensory III Flashcards
purpose of paleospinothalamic system
alarm/alerting system that triggers protective reflexes
where does the paleospinothalamic system relay nociception to
reticular formation hypthalamus thalamus midbrane limbic ssytem
what type of pain does the paleospionothalamic system trigger
slow, dull, poorly localized
what type of pathway is teh paleospinothalamic system
multisynaptic
what type of neurons does the paleospinothalamic system have
I and II
what are teh fibers in the paleospinothalamic system
C fibers
c fibers
non-myelinated, thin diameter
what happens when central process enters the spinal cord
bifurcates into short ascending and descending fibers
what happens when central process enters the spinal cord
bifurcates into short ascending and descending fibers
spinohypothalamic tract
AND reflex responses
spinoreticular tract
sets off alarm in response to pain
reticular formation
arousal, wakefulness, alertness
limbic system
emotional/affective
what does the second order neuron join with
spinoreticular tract, gives rise to collateral branches along its ascending path
where do collateral branches terminate
reticular formation
where does spinotectal tract go to
acends up to midbrain, terminates in superior colliculus
superior colliculus
nucleus lcoated on dorsal aspect of midbrain
part of visual system
what does superior colliculus give rise to
tectospinal tract
where does tectospinal tract go
descends down to the spinal cord, synpases with motor nerous and interneurons in cervical adn thoracic spinal cord levels
where is the hypothalamus located
in diencephalon
hypothalamospinal tract
terminated in the laterla horn of spinal cord levels T1-L2. stimulates preganglionic sympathetic nerve cell bodies
what does hypothalamospinal tract cause
increase in HR, breathing rate, bp
where is red neuron located
projects from reticular formation up to the thalamus
where do fibers that terminate in teh reticular formation synpase
in intralaminar nuclei of the thalamus
where do fibers that terminate in teh reticular formation synpase
in intralaminar nuclei of the thalamus
a lesion in the spinothallamic tract usually results in what
diminution or less of pain and temp senstion on the contralateral side of teh body 2 or more segments below the level of lesion
what type of tract is the spinothalamic tract
crossed
convergence-projection theory of visceral pain
pain is from visceral structure but brain think it is coming form upper limb
what happens if you have cavitation of cervical spinal cord
central canal of spinal cord becomes enlarged, certain fivers become stretched
what are the first things damaged with syringomyelia
decussating fibers from anterior wide commissure
what does lesion in medial surface of S-I cortex cause
contralateral leg and foot
what does lesion in lateral surface of SI cortex cause
sensory deficit in contralateral UL and face
what do lenticulostriate a supply
anterior and psoterior limbs of internal capsule
what happens if you have a blockage in posterior cerebral a that supplies midbrain
pain and temp deficients in contralateral side of body
what do ALS ascending fibers get blood supply from
basilar a
blcokage in paramedian branches of basilar a causes what
deficients in opposite side of body
blcokage in branches of vertebral a supplying ALS casues waht
deficients in contralateral side of body
