brain control of voluntary mvts Flashcards
pyramidal tract
cs
extrapyradmial tracts
rubro, reticulo, vestibulospinal
cerebellum involvement in mvt
timing and accuracy
do cortex and brainstem have direct access to motor neurones
yes
do basal ganglia and cerebellum have acces to motor neurones
no
prefrontal cortex does what
cognitive control -> executive function = switch out of habits = goal oriented behaviour
lesion of prefrontal cortex
behaviour becomes automatic, habitual, stimulus-driven, dramatic change in personality
dorsolateral prefrontal cortex which BA areas
9, 46
dorsolateral prefrontal cortex takes stimulus from
external environment
what BA area is frontal pole
10
dorsolateral prefrontal cortex lesion (5)
lack of planning ability
apathy
can’t sequence actions and tasks
poor working memory spatial (r)
poor workin memory verbal (l)
what is a good test for cognitive flexibiltiy (ability to switch)
Wisconsin card sorting test
medial prefrontal cortex
choosing response in light of knowledge and past experience (ie internal stimulus)
medial prefrontal cortex may be aberrant in which condition
autism
what is BA 11
orbitofrontal cortex
what is orbitofrontal lesion
blunted or dysregulated emotional experience
lack of persistence,
lack of planning
social inappropriateness
what does anterior cingulate cortex do, when is it busiest
monitoring ongoin tasks, busiest with more complex/demanding tasks
broca’s areas is in
left hemisphere frontal lobe
supplementary area has strong association with
medial frontal cortex
which regions make a actual plan for purposeful action
pre-SMA (supplementary motor area) and SMA
what does the Supplementary motor area do
organises actions bases on internal goals, makes a plan or sequence fo learned actions(eg play the piano)
damage of SMA
can’t execute well learned behaviours (eg play the piano)
premotor cortex has strong reciprocal connection with
parietal lobe
which circuit is involved when external cues (eg a ball is thrown at you)
parieto-premotor-primary motor cortex
premotor cortex is stimulated by..
external stimuli
loss of 2ary motor area
apraxia (dyspraxia if mild)
what is fine in dyspraxia
desire to perform
muscle tone
primary motor cortex is which BA
4
lesion of primary motor cortex (M1)
paralysis
what is Bereitshaftspotential
readiness potential
where is the efference copy of any motor plan sent
posterior parietal cortex
what sort of neurones are in the dorsal striatum
medium spiny neurones
what neurotransmitters from where input into the medium spiny neurones of the dorsal striatum
glutamine from the cortex
dopamine from substantia nigra pars compacta
gaba from local interneurones
globus pallidus internal output projects to…
VA and VL nuclei of the thalamus
substantia nigra is in the…
midbrain
sunstantia nigra pars reticulata output projects to…
superior colliculus (saccades) inh
Thalamus (inh direct pathway)
superior colliculus is in charge of…
head and eye mvt
Broca’s area is where (brodmann area)
BA 44 and 45 of left hemisphere
where are the frontal eye fields and what do they do
BA 8, manage occularmotor
what are small jerky movements of eyes like when readinf
saccades
where do the eyes look when having a seizure
opposite side to location of electrical activity in the brain
where do the eyes look if frontal lobe stroke involving eye fields
towards the side of the location of the stroke
where do the eyes look in pontine stroke?
opposite side to damage
where do FEFs cross over
paramedian pontine reticular information
what are saccades for
to get the desired object of attention into the fovea
what happens if BA 8 is damaged
FEFs don’t work -> oculomotor apraxia. Have to turn your head to get things into the fovea
what is the role of Broca#s area
planning (not producing) speech
The sensory representation of words happens in the:
temporal cortex (before broca’s area)
what is it called when a pt has damage to Brocas area and what are the symptoms
aphasia
speaks in short or incomplete sentences
no problem understanding
what do fefs do (frontal eye fields)
coordinate eye movements and gaze shifting for orienting and attentio
the corticospinal tract has monosynaptic connections ONLY with motor neurones of the … and …
thumb and digits
the corticospinal tract has what sort of synapses everywhere but thumbs and digits
excitatory and inhibitory interneurones which influence flexors and extensors respectively
what is the role of the anterior CST and where does it decussate
voluntary mvts of the trunk
decussates at the spinal level it exits
where does the CST travel
internal capsule
In the ventral horn, the α motor neurons supplying distal extensor muscles are located… and…
laterally and ventrally
In the ventral horn, the α motor neurons supplying proximal flexor muscles are located… and…
medially and dorsally
where does the anterior CST extend to
mid thoracic level
each side of the forehead has motor innervation from..
both hemispheres of the brain
lower part of the face has motor innervation from
contralateral corticobulbar tract
which side has forehead sparing in a umn lesion
contralateral side to lesion
where are the red nuclei
midbrain
does rubrospinal tract cross
ye
where does ruubrospinal tract cross
midbrain
what does rubrospinal do
extensors and flexors of upper limb
does rubrospinal control lower limb
no
which 2 tracts involved in maintenance of posture
reticulospinal
vestibulospinal
what is the difference between medial and lateral vestibulospinal tracts
medial does head and neck, antigravity muscles whereas lateral does lower limb
what causes spasticity
UMN lesion
what is a series of jerky mvts following sudden stretching of the muscle
clonus
what is happenign here
decorticate rigidity. Legs extended but arms flexed. Lesion on CST above red nucleus
lesion on CST below red nucleus
