Coricomotor System Flashcards
What are the 3 stages of events that occur before voluntary movement
- where is the thing
- are you going to move the thing?
- move the thing?
what brodman’s area is the primary motor cortex
4
cingulate motor cortex
3 small motor areas in the rostral cingulate gyrus
function of reticulospinal tracts
control of axial and proximal motor pathways
what happens if you cut the reticulospinal tracts
spasticity (maybe)
medial system motor pathways
reticulospinal tracts
lateral system motor pathways
rubrospinal tract
function of rubrospinal tract
control distal and proximal muscles of upper extremity
where does red nucleus recieve most of its input from
cerebellum and primary motor complex
what do rubrospinal tract fibers intermingle with after they cross
lateral corticospinal tract
origin of motor corticobulbar fibers
motor areas of cerebral cortex that control muscles of head and neck
path of corticonuclear fibers
pass through genu of IC, the crus cerebri of midbrain
what type of fibers do corticonuclear tracts have
motor and senosry
what are 2 components for corticospinal tract
lateral and anterior/.ventral
where do lateral corticospinal tract fibers cross
level of medulla
what do lateral corticopsinal tracts innervate
lateral neurons in ventral horn that control distal muscles
what is most of the fibers from corticospinal tract
in lateral corticospinal tract
where do anterior or ventral corticospinal tracts cross
in spinal cord just before synpasing on neurons/internors that control axial and prozimal limb muscles
do all anterior or ventral corticospinal tracts cross
no
generally what is lateral corticospinal tract necessary for
fractionation of movement
fractionation of movement
ability to activate individual muscles independently of other muscles
what happens to monkeys who have their corticospinal tracts cut at medullary pryamids
can’t grasp an object with 2 fibers
can walk/climb and don’t have spasticity
what does anterior cerebral a supply
leg are of primary motor cortex, most of supplementary motor area, cingulate gyrus
what does middle cerebral a supply
trunk, hand, face area of primary motor cortex, all of premotor area
effect of lesion in primary motor cortex
weakness
persistent hypotonia
perment deficint in control o ffine, fractionated, finger movements
what is mirror neuron system involved in
encoding intentions and actions of others, imitation learning
where are mirror neurons found
premotor area
function of supplementary motor area
planning/preparing for sequential motor acts, possible postural control
what happens with unilateral SMA lesion in monkeys
unable to perform complex tasks requring both hands
damage to input to SMA in parkinson’s causes what
problems initating movement
lesion of supplementary motor complex in humans cause what
initiating or suppressing movement
function of frontal eye field
voluntary and memory guided eye movements
lesion to frontal eye field causes
premanent deficit in ability to make saccades not guided by external target
can’t volutnarily direct their eyes away from a stimulus in their visual field
what is quadriplegia caused by
high cerivcal transections
what is paraplegia caused by
transections below cervical level
hemisection of spinal cord causes what
brown-sequard syndrome
brain stem lesions causes
UMN hemiparesis contralteral to lesion
LMN w/ ipsilateral paralysis
what are the 2 pathways to control eye movement via frontal eye field
superior colliculus and vertical /horizontal gase centers
where does upper facial nerve nucleus get inforation from
both sides of cortex
what happens if you get lesion of LMN on facial nerve nucleus
ipsilateral motor deficite
what kind of projections does lower facial nerve nucleus get
contralateral
sensory function of lateral corticospinal tract
facilitate/suppress transmission of afferent input to sensory relay nuclei
this could help focus attention on sensory input relevant to motor control
motor function of lateral corticospinal tract
fine control of distal extremities, coarse regulation of proximal flexors
