Tuesday 2 - trigeminal pathways

Question 1

3 central trigenimal sensory nuclei and what they do

Answer 1

Mesencephalic - proprioception of jaw, jaw jerk reflex (it’s cell bodies are within the mesencephalic nucleus) One of the only times a pseudounipolar neuron is in the CNS

Main sensory - normal touch. (“similar to normal touch dorsal column medial lemniscus pathway’)

Spinal (descending) trigeminal - nucleus. (analagous to spinalthalamic) (descends down tract, synapses in the trigeminal tract, then go up to the vpm)

Question 2

Spinal trigeminal nucleus

Answer 2

Spinal (descending) trigeminal pain neurons descend from the mid pons and go here.

Upper part of this: reflexes (e.g. eye blink)

Lower part of this: Pain and temp.

Extends from the pons to the spinal cord.

Question 3

3 areas where there is only pain sensation from the trigeminal nerve?

Answer 3

teeth, cornea, eardrum