VII- Upper Motor Neurons

Question 1

premotor cortices

Answer 1

lateral premotor cortex + supplementary motor cortex

planning and sequencing prior to move

Question 2

parts of dorsolateral

Answer 2

1. lateral corticospinal
2. rubrospinal

Question 3

mirror neurons function

in primates and humans

Answer 3

active when performing an action and observing another indiv doing the same thing
-NOT respond when context is unfamiliar

Question 4

major movements of descending motor

Answer 4

dorsolateral = flexors of extreminites
ventromedial = extensors to proximal muscles and torso

Question 5

primary motor cortex

Answer 5

@precentral gyrus

execution of contralateral voluntary movement since decussate (small proportion don’t cross)
-precise control and reg muscle contraction force

Question 6

pyramidal cells in primary motor cortex routes

Answer 6

1. most will activate interneurons in spinal intermediate zone > alpha neurons
2. some will directly monosynaptic activate alpha neurons

Question 7

inter hemispheric connection function

Answer 7

to coordinate posture by axial muscles and proximal extremities
-no connections in distal regions for greater independence

Question 8

betz cells

Answer 8

in primary motor cortex
-small proportion but large axons so fastest signaling

Question 9

ventromedial tracts

Answer 9

1. reticulospinal
2. vestibulospinal

Question 10

corticobulbar tract

Answer 10

control muscles of face, head, neck

Question 11

corticospinal tract

Answer 11

skilled voluntary movement
-direct pathway either to interneurons or distal extremity alpha neurons

Question 12

ventral corticospinal tract

Answer 12

axons descend uncrossed and terminate bilaterally
-control axial and proximal muscles for postural control of neck, shoulders, upper limb

Question 13

rubrospinal tract

Answer 13

for proximal flexor muscles + assist well learned rote movements
-from red nucleus > decussate in midbrain > interneurons for alpha

Question 14

internal capsule orientation

Answer 14

1. face (anterior)
2. arm
3. trunk
4. leg (posterior)

of posterior limb

Question 15

blood supply to internal capsule

Answer 15

lenticulostriate arteries from middle cerebral
-susceptible to stroke

Question 16

middle cerebral covers what areas

Answer 16

1. premotor lateral
2. supplemental
3. superior frontal gyrus
4. precentral gyrus