B2 Tracts Flashcards
What is the one lateral sensory discriminative pathway?
Neospinothalamic pathway
What are the 3 functions of the neospinothalamic pathway (lateral sensory discriminative)
- Interpret pain
- Organised somatotopically to permit localisation
- Small receptive site = better localisation
What are the 6 steps of the neospinothalamic pathway (lateral sensory discriminative)?
- Nociceptors → 1st → 2nd → Brainstem
- VPL thalamus - crude pain
- Internal capsule posterior limb
- Corona radiata
- Primary somatosensory cortex
- Secondary somatosensory cortex - intrepret pain
What are the 4 medial affective motivational pathways?
- Paleospinothalamic pathway
- Spinohypothalamic pathway
- Spinomesencephalic pathway
- Spinoreticular pathway
What is the function of the paleospinothalamic pathway?
Dorsomedial & intralaminar nuclei project to cortical association areas & limbic ⇒ emotion & memory
What are the steps of the paleospinothalamic pathway?
- Nociceptors → 1st → 2nd → Brainstem
- Thalamus: Dorsomedial & intralaminar nuclei
- …
- Amygdala, cingulate cortex, insula, hypothalamus
What is the function of the spinohypothalamic pathway?
Hypothalamus controls autonomic response to pain: e.g. HR, respiratory rate, sweat
What are the steps of the spinohypothalamic pathway?
- Nociceptors → 1st → 2nd → Brainstem
- …
- Hypothalamus
What is the function of the Spinomesencephalic pathway? What are the 3 functions of the peraquaductal grey?
Periaqueductal gray:
- Output to dorsal horn ⇒ modulation of pain
- Superior colliculus: ⇒ reflex eye movements toward source of pain
- Mesencephalic reticular formation – amygdala ⇒ emotional aspects of pain
What are the steps of the spinomesencephalic pathway?
- Nociceptors → 1st → 2nd → Brainstem
- …
- Periaqueductal gray
- Superior colliculus: output to tectospinal tract - look at where pain is
What is the function of the spinoreticular pathway? What are the 3 functions of the reticular formation in brainstem?
Reticular formation in brainstem:
- Output to dorsal horn ⇒ modulation of pain
- Output to ventral horn ⇒ motor response to pain
- Output to cortex, basal nuclei, cerebellum, thalamus, ⇒ arousal, attention to stimuli
What are the steps of the spinoreticular pathway?
- Nociceptors → 1st → 2nd → Brainstem
- …
- Reticular formation throughout brainstem