Flashcards in motor control 1 Deck (65)
what are the 3 levels of motor control hierarchy?
what are the structures associated with high motor control?
what are the structures associated with middle motor control?
what are the structures associated with low motor control?
what do the lateral pathways of the spinal cord control?
voluntary movements of distal muscles - under direct cortical control
what do ventromedial pathways control?
posture and locomotion - under brain stem control
where does the corticospinal tract decussate?
medulla/spinal cord junction
how do CST axons control muscles?
they synapse on ventral horn motor neurones and interneurons
where does 2/3ds of the CST originate?
areas 4 and 6 of the frontal motor cortex - rest is somatosensory
where does the rubrospinal tract originate?
red nucleus of the midbrain
what happens if there are lesions in the CST and RST?
fine movements of the arms and hands lost.
unable to move shoulders, elbows, wrist and fingers independently
what happens if there is a lesion in the CST but not the RST?
fine movements initially lost but after a few months functions reapper because the RST takes over
what does the vestibulospinal tract do?
stabilizes head and neck
what does the tetospinal tract do?
ensures eyes remain stable as body moves
where do the pontine and medullary reticulospinal tracts originate?
what sensory information do the pontine and medullary Reticulospinal tracts use?
what is the function of the pontine and medullary reticulospinal tracts?
reflexly maintain balance and body position
innervate trunk and antigravity muscles in limbs
what does the motor cortex do when complex movement is required?
directly activates spinal motoneurones and frees them from reflex control by communicating via nuclei of ventromedial pathways
where do the medial tracts of white matter originate?
where do the lateral tracts of white matter develop?
where in the brain is the primary motor cortex?
what does the cerebral cortex need to know in order to plan movement?
where the body is in space
where it wants to go
needs to select a plan to get there
what is the function of the supplementary motor area?
innervates distal motor units directly
what is the function of the premotor area?
connects reticulospinal neurones innervating proximal motor units
why is area 6 of the brain sometimes described as a "junction"?
it is where signals encoding what actions are desired are converted into how the actions will be carried out
what happens with regard to blood flow to the brain during practised voluntary finger movements?
blood flow increases in the following areas:
areas 6 and 4
if you were to "think" about making a movement, which area would be active?
area 6 but not area 4- area 4 is for "doing it"
what are the decision making neurones in command centres?
neurones in the premotor area
when are neurones in area 6 fired?
when movement is imagined
when you see others making a specific movement