Motor 1 Flashcards
what are the three motor control structure hierarchy?
- basal ganglia
- motor cortex, cerebellum
- brain stem, spinal cord
what structure has the function of strategy?
basal ganglion
what structure has the function of tactics ?
motor cortex, cerebellum
what structure has the function of execution?
brain stem, spinal cord
what do the lateral pathways of the spinal cord control?
voluntary movements
what do the ventromedial pathways of the spinal cord control?
posture and locomotion
what control are ventromedial pathways under ?
under brain stem control
what control are lateral pathways under?
direct cortical control
what does CST stand for ?
cortocospinal tract
where does most of the CST originate from?
areas 4 and 6 (frontal motor cortex)
what side of the body does the right motor cortex control?
left
what does RST stand for?
rubrospinal tract
where does the rubrospinal tract start?
red nucleus of the mid brain
what would be the clinical consequences of lesions on the CST and the RST ?
fine movements of arms and hands are lost
e.g. can stand without losing balance but can’t play an instrument
what would be the clinical consequences of a lesion on the CST and not on the RST?
fine movements of the arms and hands would be lost but after a few months they would reappear as the functions have been taken over by RST
does CST and RST have the same input areas?
yes
what two lateral pathways (pass through the lateral column of the spinal cord) control voluntary motor movements ?
CST and RST
name the two ventromedial pathways which control posture and locomotion
Vestibulospinal and Tectospinal tracts
- VST
- TST
where does the TST start?
superior colliculi of the mid brain
what is the function of TST?
ensures eyes remain able as the body moves
where does VST start?
vestibular nucleus of the medulla
what is the function of VST ?
stabilises the head and neck
what is the function of pontine and medullary reticulospinal tracts ?
maintain balance and body position
in which spinal cord column do the reticulospinal tracts pass down?
ventromedial pathway
what do the medial tracts from brainstem control?
posture, balance and orienting mechanisms.
what do the lateral tracts from brainstem control?
precise skilled voluntary movements
through which white matter do the upper motor neurons pass through in the spinal cord ?
1. upper motor neurons from the cerebral cortex
- upper motor neurons from the brain stem
- lateral white matter
2. anterior medial white matter
on which gyrus is the primary motor cortex?
pre central gyrus
are areas 5 and 7 sensory or motor ?
sensory
are areas 4 and 6 sensory or motor ?
motor
what divides the sensory and motor areas?
the central sulcus
what two parts is area 6 divided into ?
SMA - supplementary motor area
PMA - premotor area
what does the PMA connect to?
reticulospinal neurones
do SMA or PMA innervate distal or proximal motor units?
SMA = distal motor units
PMA = proximal motor units
what would be the clinical consequence of damage to the posterior parietal cortex (areas 5 and 7)?
person would not know where their body was in space
- would think half of their body didnt exist
where are decisions about what actions to take and what there likely outcome would be made in the brain?
prefrontal and parietal cortex
- P for planning
on a PET scan-
during practised voluntary finger movements what areas would light up?
areas 4 and 6
on a PET scan-
what areas would light up when thinking about an action ?
area 6
what neurones does area 4 activate ?
CST
RST
does the PMA part of area 6 fire APs when the movement is imagined ?
yes
does the PMA part of area 6 fire APs when you watch the movement done by someone else?
yes
