Test 3 -11 Flashcards
Where are the two conscious pathways located
touch and proprioception - dorsal columns
pain and temperature - anterolateral columns
What is the sensory pathway for discriminative touch and conscious proprioception?
dorsal columns and medial lemniscus
1.dorsal root gang-dorsal root-SC-caudal medulla
synapse in medulla
2. medulla to thalamus
synapse in thalamus
3. thalamus to post central gyrus of parietal lobe
What do both the primary and secondary somatosensory detect?
primary: size, texture, shape
secondary: memory of tactile
What is the sensory pathway of pain and temperature?
anterolateral columns 1. Free N endings - dorsal horn synapse 2. dorsal horn (cell body) to thalamus synapse in thalamus 3. thalamus to cerebral cortex (post-central gyrus)
Which pathway is labeled the spinothalamic pathway and what fibers does it use?
pain and temperature
LATERAL PAIN SYSTEM
A-Delta
What are the three divergent pathways for emotional and autonomic systems? What is this pathway termed? What fibers are used in this pathway? Which one uses a 3 neuron pathway?
Spinoreticular
spinomescencephalic
spino-emotional (3)
medial pain system
C Fiber
spinoreticular
synapse in BS reticular formation
to midline
to thalamus
arousal, attention and sleep wake cycles
spinomescencephalic
SC to midbrain
- turns head to noxious stimuli
- activates neurons projecting from BS -> SC to shut off pain pathway (periaqueduct)
Spino-emotional
synapses in thalamus
- alerts autonomic
- makes mad
peripheral sesnitization
Free N endings slightly depolarized
easy to reach threshold
What are the neurotransmitters of the first synapse for the spinothalamic and divergent pathways?
spinothalamic - glutamate - lateral pain - A-Delta -fast
divergent - Substance P -Medial pain - C-fiber - slow
What would an increase in Glutamate elicit?
Fast pain by A-Delta fibers with spinothalamic pathway
What would an increase in Substance P elicit?
Slow pain bu C-Fibers with divergent pathways
What is a possible mechanism of referred pain?
afferents and somatics converge with spinothalamci
What are the 3 aspects of the pain experience?
- sensory
- motivational
- cognitive
Suppressed dorsal horn processing
cannot pass AP, rub it
sensitized (temporary) dorsal horn processing
neuropathic
increased neurotransmitters for temporary time from presynaptic cleft
reorganized persistent
neuropathic
remap - LTP - PERMANENT
What are the five sites of antinociception?
- Peripheral
- Dorsal horn
- midbrain descending
- hormonal - pituitary
- Amygdala and cortex
I. Peripheral antinociception
Free N endings
reduce depolarization of Substance P
stretch, mobilize, anti-inflammation, massage
II. Dorsal Horn antinociception (1st synapse of Pain pathway)
Rub it where it hurts
moving activates mechanoreceptors - polarize A-Beta
E-Stim
III. Midbrain descending antinociception
returns to site of P
narcotics
IV. Hormonal - pituatary antinoception
autonomic - dump chemicals into blood
pharmacological
endogenous opioids
V. Amygdala and cortex antinoception
THINK
can turn on inferior levels
Which antinociception pathways do we have the most control over?
I, II, & V
