@chronicburn
@Sjtof
I think this explains very well why neck/cervical issues could cause serious ear pain, and mimic a lot of ear related symptoms like ETD, infections, ear pain etc. (Just a thought).
The spinal trigeminal nucleus (can be seen on the nerve chart a couple posts above) carries sensory information from CN: V (trigeminal), VII (facial), IX (glossopharyngeal) and X (vagus) and is located in the medulla, below the pons.
( Image source: Wikipedia )
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( Source: http://www.neuroanatomy.wisc.edu/virtualbrain/BrainStem/03CNV.html )
I am sorry to say that the spinal tract and spinal nucleus V are not exclusively associated with C.N. V. It is also associated with C.N.s VII (facial), IX (glossopharyngeal) and X (vagus). While this makes the story a little confusing, it also makes a lot of sense! The pain and temperature fibers associated with C.N. VII innervate the skin of the external ear, the wall of the external auditory meatus and the outer surface of the tympanic membrane (if it's OK with you, I'll lump these together as "EAR"). These fibers are the peripheral processes of cells that lie in the GENICULATE ganglion (located in the facial canal). The central processes of these neurons enter the brain with C.N. VII (at pontine levels, caudal to the trigeminal), travel in spinal tract V and end in spinal nucleus V. The pain and temperature information is then conveyed rostrally in the TTT (trigeminothalamic tract) to reach the VPM, from which it is relayed to somatosensory cortex (areas 3,1 and 2). Thus the pain and temperature fibers of C.N. VII don't have their "own" central cell group, but instead use that of the trigeminal.
@Sjtof
I think this explains very well why neck/cervical issues could cause serious ear pain, and mimic a lot of ear related symptoms like ETD, infections, ear pain etc. (Just a thought).
The spinal trigeminal nucleus (can be seen on the nerve chart a couple posts above) carries sensory information from CN: V (trigeminal), VII (facial), IX (glossopharyngeal) and X (vagus) and is located in the medulla, below the pons.
( Image source: Wikipedia )
-------
( Source: http://www.neuroanatomy.wisc.edu/virtualbrain/BrainStem/03CNV.html )
I am sorry to say that the spinal tract and spinal nucleus V are not exclusively associated with C.N. V. It is also associated with C.N.s VII (facial), IX (glossopharyngeal) and X (vagus). While this makes the story a little confusing, it also makes a lot of sense! The pain and temperature fibers associated with C.N. VII innervate the skin of the external ear, the wall of the external auditory meatus and the outer surface of the tympanic membrane (if it's OK with you, I'll lump these together as "EAR"). These fibers are the peripheral processes of cells that lie in the GENICULATE ganglion (located in the facial canal). The central processes of these neurons enter the brain with C.N. VII (at pontine levels, caudal to the trigeminal), travel in spinal tract V and end in spinal nucleus V. The pain and temperature information is then conveyed rostrally in the TTT (trigeminothalamic tract) to reach the VPM, from which it is relayed to somatosensory cortex (areas 3,1 and 2). Thus the pain and temperature fibers of C.N. VII don't have their "own" central cell group, but instead use that of the trigeminal.