Motor Pathways Flashcards
General rules of which system?
*Voluntary control of distal movement AND under direct cortical control
Lateral pathway
General rules of which system?
*control of posture and movement AND under brain stem control
Ventromedial pathway
2 major lateral pathways
- corticospinal
2. corticobulbar
Which pathway?
*originates in areas 4 (m1) and 6 (SMA, PMA0
corticospinal
Which pathway?
*fibers arise from head/face region of primary motor cortex
corticobulbar
Corticospinal tract
motor cortex –> spinal cord –> alpha motor neuron –> muscle contraction
Which pathway?
*crucial for voluntary control and precise movement
corticospinal
Which areas (4 areas) are origins on the corticospinal tract?
- primary motor cortex (30%)
- premotor and supplemental motor (30%)
- primary somatosensory cortex (31%)
- parietal areas (5, 7, 39, 40) (9%)
What goes into M1 (Primary Motor Cortex)?
know that many interactions are reciprocal!!
cortical input
- primary sensory
- supplemental and premotor
- visual
- auditory
subcortical (indirect) input (via thalamus)
- cerebellum
- basal ganglia
Primary Motor Cortex (M1) action involves all of the following EXCEPT:
- M1 neurons fire just before a movement
- projects primarily to lumbar cord levels only
- some fibers can control both antagonist and agonist activity
- controls isometric and dynamic movements
- projects primarily to lumbar cord levels only
* projects primarily to lumbar AND cervical cord levels
Primary Motor Cortex (M1) action involves all of the following EXCEPT:
- controls velocity and direction of movement
- receives vestibular feedback during movement in an ongoing manner and will alter firing in response to such input
- receives vestibular feedback during movement in an ongoing manner and will alter firing in response to such input
* receives somatosensory feedback
TRUE/FALSE
Parietal cortex involves areas 3, 2, 1, & 5 for movement
FALSE
*areas 5, 7
Which part of the coretx has the highest level of motor control?
parietal (area 5, 7)
Parietal and Prefrontal cortex projects to which area?
Area 6: where “what” actions are needed becomes converted to “how” actions will be carried out
TRUE/FALSE
Supplemental Motor Cortex cells are active about 1 second before muscle activity
TRUE
*an eternity!!!! so it does a lot of integration (multisensory) to get things planned
Which 2 areas give the supplemental motor cortex inputs?
- BG
2. posterior parietal cortex
Name the 3 roles of the Supplemental Motor Cortex.
- coordinates voluntary movement
- postural adjustments
- planning and preparation for movement, particularly self-inititated (BG)
Which is NOT a typical damage to SMA?
- bradykinesia
- akinesia
- loss of facial expression
- bradykinesia
Which is NOT a typical damage to SMA?
- difficulty with tasks requiring interaction of both hands
- difficulty initiating movement (can respond to sensory cues to begin movement)
- cerebellar interaction is deleted
- cerebellar interaction is deleted
Which is NOT a typical damage to PMA?
- akinesia
- clumsy, slow movement
- proximal weakness
- perseveration may develop, and rhythmic movements are disrupted
- akinesia
* apraxia