Motor Systems

Question 1

parts of CNS involved

Answer 1

1. motor cortex
2. thalamus (gateway to cortex)
3. basal nuclei/ganglia
4. cerebellum
5. brain stem
6. spinal cord

Question 2

control of voluntary movement path

general

Answer 2

1. association cortex = desire/idea to move starts here
2. premotor cortical area = plan of movement
3. primary motor cortex = execution of move initiated

Question 3

motor messages arise from which cortical areas

Answer 3

1. frontal lobe = primary motor cortex and premotor cortical areas (SMA, PMC, FEF)
2. parietal lobe = posterior parietal cortex

all 3 areas make up motor cortex

Question 4

premotor cortical area function

Answer 4

aka SMA + PMC
-forms plan of movementthen transmits to primary motor cortex for execution
-control axial/trunk and proximal limb muscles of UL and LL
-orient trunk and or limbs toward intended direction of move

supplementary motor area, premotor cortex

Question 5

frontal eye field

Answer 5

projects to brain stem centers that control ocular movements
-coordinates eye move
-role in visual tracking across the visual field

Question 6

posterior parietal cortex

PMA

Answer 6

visual guidance of movement
-evals location or position of body/limbs
-forms movement plan to accomplish a task or reach target

Question 7

primary motor cortex

Answer 7

@precentral gyrus of frontal lobe
-execution of distinct, well defined, vol movement to opposite side body

UMN cell bodies and axons form descending motor tracts that end in brain stem and spinal cord from pyramidal layer of cortex

Question 8

upper motor neurons

Answer 8

cell bodies @ motor cortex and motor nuclei in brain stem

axons descend in motor tracts to brain stem and SC to transmit messages from cortex to LMNs