Exam #1: Sensory III Flashcards
Where does the Paleospinothalamic System relay nociception form the body to?
- Retircular formation
- Hypothalamus
- Thalamus
- Midbrain
- Limbic System
Does the nociception from the Paleospinothalamic System reach consciousness?
NO–serves as an alert system that triggers protective reflexes
What tracts of the ALS compose the Paleospinothalamic System?
- Spinoreticular
- Spinohypothalamic
- Spinomesencephalic
- Spinotectal
What types of sensations are relayed by the Paleospinothalamic System?
Slow, dull, poorly-localized pain sensation
Where are the neurons for the Paleospinothalamic System
1) Cell body DRG
2) Dorsal horn
3) Third order is unclear…
What types of fibers carry initial sensory information from the free nerve ending nociceptors?
C–unmyelianted (thin)
What is the function of the reticular formation?
Arousal
Wakefulness
Alertness
What is the function of the spinoreticular system?
Set of the body’s alarm system in response to pain
Where does the spinotectal tract terminate? What is the function of this tract?
Superior colliculus, which then sends signals back down to motor neurons to turn your head, eyes, and trunk in the direction of the noxious stimulus
Where does the spinohypothalamic tract terminate? What is the function?
- Hypothalamus
- ANS reflex responses i.e. hypertension, tachycardia, tachypnea
What is the spinomesencephalic tract?
Tract to the midbrain, specifically the periaquetductal gray matter (PAG) that contains neurons that descend down to the brainstem that modulate nociception
What part of the thalamus do the reticular fibers synapase with? What is the implication
Intralaminar nuclei
*These are NOT somatotopically organized–difficult to localized the origin of pain
What does the limbic cortex do in regards to pain?
This is the emotional/suffering component of pain
*Lesion= patient does NOT complain of pain
