Upper Motor Neuron Systems

Question 1

What is the function of the

primary motor cortex

Answer 1

to encode movement intentions and directions

Question 2

What cells are involved in voluntary movement

Answer 2

pyramidal betz cells in region 5

Question 3

Compare and contrast primary motor to somatosensory cortices

Answer 3

somatosensory- mapping of specific body part to specific spot on cortex

primary cortex-encode movement intentions; mapping of body to spot on cortex is more generalized

Question 4

What are the two broad motions encoded by primary motor cortex

Answer 4

1. hand to mouth

2. central person space ( space in front ocular-torso region)

Question 5

Where do axons of upper motor neurons from primary cortex end in spinal cord?

Answer 5

the lateral white matter tracts and cross at midline of spinal cord to contralateral side

Question 6

Function of upper motor neurons from primary cortex control

Answer 6

control motor behaviors that require skills

Question 7

Function of upper motor neurons from brainstem control

Answer 7

control posture muscles

Question 8

Where do upper motor neurons from brain stem end where spinal cord?

Answer 8

the antero-medial white matter tracts on ipsilateral and contralateral sides of spinal cord

Question 9

What is the parallel pathway

Answer 9

pathways from primary motor cortex and brainstem that are related and occurring at same time BUT start and stop at different locations

Question 10

what are the two regions of the motor cortex

Answer 10

1. pre-motor

2. primary

Question 11

what location w/in thalamus does the motor cortex get info from?

Answer 11

Ventral anterior/Ventral lateral nuclei or VA/VL complex

Question 12

Describe cortico-spinal tract

Answer 12

Describes a path of upper motor neurons take from brain cortex to spinal cord ; related to parallel pathway

Question 13

Describe the cortico-bulbar tract

Answer 13

Describes a path of upper motor neurons take from brain cortex to brainstem ; related to parallel pathway

Question 14

How is the premotor cortex organized?

Answer 14

• has six layers

- two areas; lateral and supplemental

Question 15

What is the function of the pre-motor cortex?

Answer 15

To plan motion

Question 16

compare and contrast func of primary and pre motor cortex

Answer 16

primary-movement intentions

pre-plan movement

Question 17

State function of vestibulospinal tract in brainstem

Answer 17

Mediate feedback mechanism ; in lateral nucleus correct motions under feet and medial nucleus, vestibular sense or sudden rotation of head

Question 18

State the function of the reticulospinal tract in brain stem

Answer 18

Mediate anticipatory adjustments

Question 19

What is mirror motor neuron activity

Answer 19

neurons that are unique aspect of pre-motor cortex; activated when mirroring a modeled motion

Question 20

Describe the emotional motor system

Answer 20

extrapyramidal cells from limbic center and hypothamuls that is associated with general is with genuine emotion affecting muscle movement and tension; is a parallel pathway to volition movement

Question 21

What are the signs of upper motor neuron syndrome damage

Answer 21

-weakness
 mild to no atrophy
-generalized muscle injury
-hyperactive deep reflexes
-Babinskis' sign ( extend toes when bottom of feet is touched)

-impairment of fine voluntary motions