Upper Motor Neuron Systems Flashcards
What is the function of the
primary motor cortex
to encode movement intentions and directions
What cells are involved in voluntary movement
pyramidal betz cells in region 5
Compare and contrast primary motor to somatosensory cortices
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
What are the two broad motions encoded by primary motor cortex
- hand to mouth
2. central person space ( space in front ocular-torso region)
Where do axons of upper motor neurons from primary cortex end in spinal cord?
the lateral white matter tracts and cross at midline of spinal cord to contralateral side
Function of upper motor neurons from primary cortex control
control motor behaviors that require skills
Function of upper motor neurons from brainstem control
control posture muscles
Where do upper motor neurons from brain stem end where spinal cord?
the antero-medial white matter tracts on ipsilateral and contralateral sides of spinal cord
What is the parallel pathway
pathways from primary motor cortex and brainstem that are related and occurring at same time BUT start and stop at different locations
what are the two regions of the motor cortex
- pre-motor
2. primary
what location w/in thalamus does the motor cortex get info from?
Ventral anterior/Ventral lateral nuclei or VA/VL complex
Describe cortico-spinal tract
Describes a path of upper motor neurons take from brain cortex to spinal cord ; related to parallel pathway
Describe the cortico-bulbar tract
Describes a path of upper motor neurons take from brain cortex to brainstem ; related to parallel pathway
How is the premotor cortex organized?
- has six layers
- two areas; lateral and supplemental
What is the function of the pre-motor cortex?
To plan motion
compare and contrast func of primary and pre motor cortex
primary-movement intentions
pre-plan movement
State function of vestibulospinal tract in brainstem
Mediate feedback mechanism ; in lateral nucleus correct motions under feet and medial nucleus, vestibular sense or sudden rotation of head
State the function of the reticulospinal tract in brain stem
Mediate anticipatory adjustments
What is mirror motor neuron activity
neurons that are unique aspect of pre-motor cortex; activated when mirroring a modeled motion
Describe the emotional motor system
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
What are the signs of upper motor neuron syndrome damage
-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
