Spinocerebellar/Trigeminal Flashcards
What are the 3 spinocerebellar pathways
ventral spinocerebellar
Dorsal spinocerebellar
Cuneocerebellar
How many order neurons does the spinocerebellar path have
1st and 2nd order neurons
bypass the thalmus
What are the sensory receptors of the spinocerebellar pathway
Pancian/ruffini corpuscles (in articular capsul)- A beta fibrs
mm spindles- alpha a fibres
What is the first order neuron of ventral spinocerebellar tract (+ origin lvls)
DRG below L2/3 and then synapse in lamina 7
What is the first order neuron of the dorsal spinocerebellar tract (+ origin lvls)
DGR C8/t1-L2/3 andthen synapse in dorsal nucleus of clarke
What is the first order neuron of the cunaocerbellar fibres (+ origin lvls)
DRG c2-8 and enter and bypass grey matter to synapse at accessory cuneatus nucleus
Path of 2nd order neuron of ventral spinocerebellar tract
From lamina 7 (2nd order) cross midline thy ant white commisure and ascend as ventral spinocerebellar tract. At midbrain they cross back thru sup medullary vellum to project to IL cerebellum
Functions of ventral spinocerebellar tract
unconsious prop of lower limbs
2nd order neurons of dorsal spinocerebellar tract and path
dorsal nuc of clarke (2nd order). axons enter IL white column (post) and project into the IL cerebellum
Function of dorsal spinocerebellar tract
Inconsious prop of trunk/axial mm
2nd order neurons of coneocerebellar tract and patj
accessory cunate nucleus in medulla (2nd). axons leave and enter into Inf cerebellar peduncle to project to IL cerebellar hemisphere
Function of cuneocerebellar tract
unconsous prop of upper limbs/neck
What oocurs in brown sequard syndrome
spinal cord hemisection but symptoms of ataxia are masked because of damage to lat corticospinal tract
What is hereditary spinal ataxia and what does it affect
early onset (10-15y old) with degeneration of ventral spinocerebellar tract and dorsal spinocerebellar tract
What is the function of the trigeminal pathway
all sensations from CL face/neck
What is the first order neuron of the trigeminal pathway
trigeminal ganglion
How do general sensory signal project to the 2nd order neuron in the trigeminal path
pass thru trigeminal ganglion forming sensory root of trigeminal n and project to chief sensory/pontine nucleus
How do pain signals project to the 2nd order neuron in trigeminal path
form spinotrigeminal tract and descend thru medulla to synapse on different parts of spinal root of trigeminal n (lower down is lower on the face)
What does the spinal nucleus of trigeminal also get input from
CN7, 9, 10
Path of proprioceptive signals of trigeminal
bypass trigeminal ganglion and synapse in mesenphalic nu in midbrain
What does the mesenpahlic nuc have connection w
relay local signals into motor nuclei of trigeminal, facial anmbigous, hypoglossal to create unconscious awareness of these mm
Where are the second order neurons in trigeminal pathway (3)
chief sensory/ponite nuc
spinal nuc
mesencephalic nuc
Path from second order neurons to third in trigeminal path
axons cross midline @ medulla and form CL trigeminal lemniscus and travel up referred to as ventral trigeminal thalamic fibres
3rd order neuron of trigeminal path
VPM and travel to inf 1/3 of post central gyrus
In lat medullary syndrome what would be affected in trigeminal
loss of pain/thermal sense on CL side of face
What will damage to trigeminal root ganglia cause
CL loss pain/thermal/touch og gace
loss of corneal reflex
paralysis off masticatory mm on left
What would a lesion in the thalmus or post central gyrus cause
all sensation lost CL
