corticospinal and corticobulbar pathways

Question 1

voluntary movements are carried out by the __________for the body

Answer 1

corticospinal tract

Question 2

voluntary movements for the face are carried out by the ___________

Answer 2

corticobulbar tracts

Question 3

most of the fibers that come from the cerebral cortex down into the spinal cord cross at the ___________ through the ______________

Answer 3

lower medulla, pyramidal decussation

Question 4

motor information for the right side of the body is from the _______ side of the brain

Answer 4

left

Question 5

motor information for the left side of the body is from the ___________side of the brain

Answer 5

right

Question 6

primarily ipsilateral and facilitory to axial and limb musculature, especially the extensors and works with the medial vestibulospinal tract

Answer 6

pontine (medial) reticulospinal pathway

Question 7

bilateral (greater ipsilateral) and is facilitory to flexor musculature and inhibitory to axial and limb extensor musculature

Answer 7

medullary (lateral) reticulospinal pathway

Question 8

ipsilateral and excitatory on extensors of lower extremity musculature (inhibits flexor musculature)

Answer 8

lateral vestibulospinal pathway

Question 9

projects bilaterally and descends only to vervical and upper thoracic levels. Controls neck and upper thoracic musculature

Answer 9

medial vestibulospinal pathway

Question 10

descends only to cervical levels and coordinates neck movement towards a stimulus

Answer 10

tectospinal pathway

Question 11

not used as much now that humans are bipeds. current thinking is it is used up distal flexor activation of upper extremities

Answer 11

rubrospinal pathway

Question 12

the medial activation system is used to innervate which types of muscles?

Answer 12

postural movements and activities

Question 13

the lateral activation system is used to innervate which type of muscles?

Answer 13

distal limb musculature (fractionated movement)

Question 14

where is the medial activation system located in the spinal cord?

Answer 14

anterior funiculus

Question 15

the medial activation system consists of:

Answer 15

anterior corticospinal, medial reticulospinal, medial/lateral vestibulospinal, and tectospinal pathways

Question 16

the lateral activation system consists of:

Answer 16

lateral corticospinal, rubrospinal, and lateral reticulospinal

Question 17

what is the purpose of the primary somatosensory cortex?

Answer 17

function as a feedback mechanism that integrates cortical understanding of sensation with incoming sensory information

Question 18

what do the raphespinal, cerulospinal, spinomesencephalic, and spinoreticular pathway do?

Answer 18

they modulate the incoming pain stimuli

Question 19

in the corticobulbar system what areas are exceptions to the bilateral innervation rule?

Answer 19

facial motor nucleus, hypoglossal nucleus, extraocular eye muscle

Question 20

what are lower motor neurons?

Answer 20

they are found in the ventral horn and leave the spinal cord to innervate skeletal muscle. they are the ones we saw in anatomy lab

Question 21

what are the symptoms of lower motor neuron loss?

Answer 21

flaccid paralysis, areflexia or hyporeflexia, atrophy of muscle, fasciculations and fibrillations

Question 22

what are upper motor neurons?

Answer 22

they are located at suprasegmental levels of the CNS and end in the ventral horn.

Question 23

what are the symptoms of upper motor neuron loss?

Answer 23

initial flaccid paralysis (spinal shock), abnormal cutaneous reflex, abnormal reflex, spasticity, abnormal timing of muscle activaiton, paresis or plegia