Pain pathways of head and neck and reflexes Flashcards
Describe the route of the ascending pain pathway
Synapses in the dorsal horn of the spinal cord and decussates, ascends contra laterally to the ventral posterior nucleus of the thalamus, tot he sensory cortex
Describe the route of the descending pathway that inhibits pain
Originates for periaqueductal grey in the midbrain.
Synapses in the nucleus raphe in the medulla, onto the spinal cord where it inhibits pain pathways by interneurones
To what nuclei does the corticobulbar fibres provide bilateral innervation?
V and VII (upper face), XII except for genioglossus which is contralateral
To what nuclei does the corticobulbar fibres provide contralateral innervation?
VII lower face
To what nuclei does the corticobulbar fibres provide ipsilateral innervation?
XI
To which nuclei do corticobulbar fibres provide contralateral innervation from frontal and parietal eye fields?
II, IV, VI
What does the trgeminal nerve provide sensory innervation in the head and neck to?
Muscle of facial expression, nose, orbit, meninges,
Through what nerve do pain afferents form the ear canal travel?
VII
Through what nerve do pain afferents from posterior 1/3 of tongue travel?
IX
What fibres transmit sharp pain from teeth?
A fibres
Why can changes in temperature to teeth cause pain?
A fibres can extend into dentinal tubules
What fibres transmit dull aching pain from teeth?
C fibres
To which nucleus does all pain from he head and neck synapse?
Spinal root of V
Where are the sensory aspects fo pain processed?
Somatosensory cortex
Where are the emotional aspects of pain processed?
Anterior cingulate cortex
