6 Trigeminal Pathways - M Flashcards
(64 cards)
Where are the cell bodies of CN 5 afferents primary located?
trigeminal/semilunar ganglion
What are the 4 major nuclei of the trigeminal tract?
- main/primary sensory nucleus (msT)
- trigmeninal motor nucleus (mT)
- spinal nucleus
- mesencephalic nucleus (mes)

Where is the main sensory nucleus (msT) found?
in the mid pons enlargement lateral to trigeminal motor nucleus (mT)

Which trigeminal nucleus extends rostrally?
Mesencephalic nucleus (mes)

Which trigeminal nucleus extends caudally into the cervical region?
Spinal nucleus

What afferents modalities are transmitted to the cortex via the primary sensory nucleus (msT)
discriminative tactile & proprioceptive senstations
What afferent modalities are transmitted via the spinal nucleus?
pain & temperature
What afferent modalities are transmitted via the mesencephalic nucleus (mes)?
proprioceptive afferents from the muscles of the mastication & the TMJ
Identify the following structures

- mesencephalonic nucleus
- main sensory nucleus
- trigeminal ganglion
- spinal (trigeminal) nucleus

What is the primary sensory afferent of the head and face?
Trigeminal nerve (V1, V2, V3); review distribution
What are the 2 divisions of the main sensory nucleus (msT)?
dorsomedial & ventrolateral divisions

What afferents are associated with the dorsomedial division of the msT
afferents from oral cavity

What afferents are assoicated with the ventrolateral division of the main sensory nucleus?
V1-V3

2nd order afferents of the msT nucleus project to what nucleus in the thalamus?
VPM

2nd order afferents from the ventrolateral division of the msT project to ____ VPM via what tract?
Contralateral VPM via the anterior trigeminothalamic tract

2nd order neurons from the dorsolateral division of the msT project to ___ VPM via what tract?
ipsilateral VPM via the posterior trigeminothalamic tract/ dorsal central trigeminal tract

fibers of the ventrolateral msT are joined by fibers from what other nuclei in the VPM?
spinal trigeminal nucleus to form the trigeminothalamic lemniscus
Through what brainstem structure does the dorsal central trigeminal tract ascend through?
The periaqueductal gray matter (surrounds cerebral aqueduct in the midbrain)
Where are tertiary neurons of the trigeminal pathway located?
cell bodies in the VPM and project to the primary somatosensory cortex
Tertiary neurons of the VPM project via what structure to reach the post-central gyrus?
The posterior limb of the internal capsule
What part of the head receives sensory innervation from the trigeminal nerve?
The anterior half
trigeminal afferents carrying pain & temp info enter ___ nucleus and then DESCEND via what tract?
enter spinal nucleus and DESCEND via spinal trigeminal tract before ascending via anterior trigeminothalamic tract

What are the 3 regions of the spinal nucleus?
- Pars/subnucleus CAUDALIS
- pars/subnucleus oralis
- pars/subnucleus interpolaris
4.

How are the afferent TO the ventrolateral msT organized?
V1 =posterior, V2 = middle, V3 = anterior/ventral
