Term
| What are the 3 levels of control in the motor system and what are they important for? |
|
Definition
Spinal cord-simple muscle contractions and movements
Brain stem-receive info from spinal cord and send info back down
Cerebral cortex-voluntary movement, can send direct pathway to motor cortex to spinal cord or to the brain stem |
|
|
Term
| Which level of control in the motor system is important for fine motor and fine voluntary movement/skilled movement? |
|
Definition
|
|
Term
| Which level of control in the motor system is important for postural control; control of orienting to sensory stimulations, locomotion, and oral/facial behavior (eye movements)? |
|
Definition
|
|
Term
| What is it call when an animal without a cortex can be stimulated in the brainstem to elicit normal locomotive behavior? |
|
Definition
| fictive/fictitious locomotion (but will need motor cortex if you want control of it) |
|
|
Term
All 3 levels of the motor systems are under the influence of what 2 independent subcortical systems?
These 2 systems act on the cerebral cortex through relay nuclei in the _________. |
|
Definition
basal ganglia and cerebellum
thalamus |
|
|
Term
| Which level of control in the motor system is important for spinal reflexes (simple motor movement)? |
|
Definition
|
|
Term
| What tract is a direct connection between the cerebral cortex to the spinal cord? |
|
Definition
|
|
Term
| What are the 3 tracts that goes from the brain stem to the spinal cord? |
|
Definition
rubrospinal
vestibulospinal
reticulospinal |
|
|
Term
In the homunculus on the ventral horn, the descending projections from the motor cortex will be in the (anterior-medial white matter or lateral white matter)?
Will this be innervating distal limb muscles or axial and proximal limb muscles? |
|
Definition
lateral white matter (lateral corticospinal tract)
distal limb muscles (skilled movements) |
|
|
Term
In the homunculus on the ventral horn, the descending projections from the brainstem will be in the (medial white matter or lateral white matter)?
Will this be innervating distal limb muscles or axial and proximal limb muscles? |
|
Definition
medial white matter (direct corticospinal tract)
axial and proximal limb muscles (posture and balance) |
|
|
Term
Do the medial motor neurons in the medial ventral horn terminate (ipsilaterally, contra laterally, or bilaterally)?
Do lateral motor neurons in the lateral ventral horn terminate (ipsilaterally, contralaterally, or bilaterally) |
|
Definition
bilaterally (wouldn't want one side of torso turning)
contralaterally |
|
|
Term
| Which descending motor pathway crosses over and sends axons down the lateral corticospinal tract (like a direct corticospinal tract) |
|
Definition
|
|
Term
The reticulospinal, medial and lateral vestibulospinal, and tectospinal tracts descend in the (lateral or ventral column)
Are these components of the medial or lateral pathway? |
|
Definition
|
|
Term
| What is the main lateral pathway that originates in the caudal, magnocellular portion of the red nucleus? |
|
Definition
|
|
Term
| Does the rubrospinal tract descend in the (ipsilateral or contralateral) dorsolateral column? |
|
Definition
| contralateral (it is the main lateral pathway) |
|
|
Term
| Where does the lateral vestibulospinal tract start? |
|
Definition
| lateral vestibular nucleus |
|
|
Term
| What descending projection from the brainstem to the spinal cord is responsible for compensatory response to postural instability (when someone pushes you)? |
|
Definition
| lateral and medial vestibulospinal tracts |
|
|
Term
| What descending projection from the brainstem to the spinal cord is responsible for stabilizing posture during ongoing movement? |
|
Definition
|
|
Term
| What descending projection from the brainstem to the spinal cord is responsible for axial muscles in the neck for orienting movements of the head? |
|
Definition
| colliculospinal tract (gets from superior colliculus-vision) |
|
|
Term
| what part of the spinal cord do descending projections from the brainstem usually stop? |
|
Definition
| cervical (info mainly involves upper body) |
|
|
Term
| The brain plans maintenance of body _______. |
|
Definition
|
|
Term
__________ postural responses are "preprogrammed" and typically precede the onset of limb movement
__________ postural responses are initiated by sensory inputs that detect postural instability. |
|
Definition
|
|
Term
| What is the indirect route of the motor cortex that influences the activity of spinal cord neurons? |
|
Definition
| neurons in the motor cortex that supply the lateral part of the ventral horn to initiate movements of the distal limbs also terminate on neurons in the reticular formation to mediate postural adjustments that support the movement. The reticulospinal pathway terminates in the more medial parts of the ventral horn, where lower motor neurons that innervate axial and proximal muscles are located |
|
|
Term
What are the cells of origin of the corticospinal fibers?
What cortical layer are these cells found (the motor output)? |
|
Definition
|
|
Term
| What are the largest corticospinal fiber cells found in layer 5? |
|
Definition
|
|
Term
True or False:
Corticospinal tract neurons (UMN) have a point-to-point topography. |
|
Definition
False
Corticospinal tract neurons (upper motor neurons) have multiple branches within the spinal cord (output of single corticospinal neuron often diverges to influence multiple muscles) |
|
|
Term
| Corticospinal tract neurons code for ______ and _______. |
|
Definition
| force and direction (increases rate when going left) |
|
|
Term
What part of the brain will have increased blood flow when related to the execution of the response?
What about the activation of peripheral receptors? |
|
Definition
|
|
Term
| What part of the brain will have increased blood flow during a complex sequence of finger movements? |
|
Definition
| extends from motor area to the supplementary motor area (involves a larger part of the brain) |
|
|
Term
| What part of the brain will have increased blood flow during mental rehearsal of complex finger movements? |
|
Definition
| supplementary motor area ONLY (planning area) |
|
|
Term
| A unilateral lesion of the supplementary motor area results in a deficit in (unimanual or bimanual) coordination/fine motor tasks? |
|
Definition
|
|
