Motor Control 1 Flashcards
areas of higher-order are involved with?
more complex tasks eg. coordinate muscle activity
areas of lower hierarchy are involved with?
lower level tasks eg. execution of movement
motor systems organised in a number of different areas that control different aspects of movement is known as?
functional segregation
what does the corticospinal tract control?
voluntary movements of body
what does the corticobulbar tract control?
voluntary movements of face
which tracts pass through the pyramids of the medulla?
corticospinal and corticobulbar
which gyrus is the primary motor cortex situated in?
pre-central gyrus
what does the motor cortex control?
fine, descrete, precise voluntary movements
what does the pre-motor area do?
planning voluntary movements
supplementary motor area does what?
involves complex movements which are generally internally driven
where does the lateral corticospinal tract decussate?
medulla
what is the lateral corticospinal tract responsible for?
limb muscle control
what is the anterior corticospinal tract responsible for?
trunk muscle control
which cortex contains neuronal cell bodies of the corticobulbar tract?
primary motor cortex
what do the motor nerves from the corticobulbar tract do specifically?
eye movements, muscles of jaw, muscles of face, tongue
what does the vestibulospinal tract do?
stabilise head during body movements coordinates head movements with eye movements mediates postural adjustments
what does the reticulospinal tract do?
changes in muscles’ tone associated with voluntary movement, provides postural stability
where does the reticulospinal tract descend from?
medulla and pons
where does the tectospinal tract descend from? What does it do?
superior colliculus of brain orientation of head and neck during eye movements
where does the rubrospinal nucleus descend from? What does it do?
red nucleus of brain innervates lower motor neurons of flexors of upper limb
loss of voluntary motor function paresis paralysis are what type of upper motor neurone lesion sign?
negative
increased abnormal motor function due to loss of inhibitory descending inputs spasticity hyper-reflexia clonus babinski’s sign are all examples of which type of upper motor neuron lesion sign?
positive
what is apraxia? What is it caused by?
a disorder of skilled movement lesion in the supplementary motor area
weakness hypotonia hyporeflexia muscle atrophy fasciculations - spontaneous twitch fibrillations of muscle fibres are all examples of which type of lesion?
lower motor neuron lesion
which neurons does motor neuron disease affect?
upper and lower motor neurons
upper: spasticity brisk limbs and jaw reflexes babinski’s sign loss of dexterity dysarthria dysphagia lower: weakness muscle wasting tongue fasciculations and wasting nasal speech dysphagia are all signs of which disease?
motor neuron disease
which structures make up the basal ganglia?
- striatum - caudate nucleus, putamen and external globus pallidus
- nucelus accumbens
- subthalamic nuclei
- substantia nigra (midbrain)
- ventral pallidum, claustrum, nucleus basalis
what is the function of the basal ganglia?
- decision to move
- elaborating associated movements
- moderating and coordinating movement
- performing movements in order
summarise the pathology of parkinson’s disease
degeneration of the dopaminergic neurons that originate in the substantia nigra and project to the striatum
What are C, P, G and T?
C - caudate nucleus
P - putamen
G - (external) globus pallidus
T - thalamus
what is bradykinesia?
slowness of small movements
what is a hypomimic face?
mask-like, expressionless
what is akinesia?
difficulty in initiation of movements
what is rigidity?
muscle tone increase, causing resistance to externally imposed joint movements
bradykinesia, hypomimic face, akinesia, rigidity, tremor at rest are all signs of?
parkinson’s disease
summarise the pathology of Huntington’s disease
degeneration of GABAergic neurons in the striatum, caudate and putamen
- choreic movements
- rapid jerky involuntary movements of the body hands and face (affected first) then legs and rest of body
- speech impairment
- difficulty swallowing
- unsteady gait
- cognitive decline and dementia in later stages
are all signs of?
Huntington’s disease
ballism - what is it? what is it caused by?
sudden uncontrolled contralateral flinging of the extremities
stroke affecting subthalamic nucleus
which part of the brain is associated with coordinating and predicting movement?
cerebellum
which structure separates the cerebrum from the cerebellum?
tentorium cerebelli
what is the green structure called and what is it involved with?
what does damage to it cause?
vestibulocerebellum
- regulation of gait, posture and equilibrium
- coordination of head movements with eye movement
damage causes syndrome similar to vestibular disease leading to gait ataxia and tendency to fall
what is this structure called?
what does it do?
what does damage to this structure cause?
- spinocerebellum
- coordination of speech and adjustment of muscle tone and coordination of limb movements
- damage is associated with chronic alcoholism and affects mainly legs, causing abnormal gait and stance (wide-based)
What is this structure called?
what does it do?
how does damage affect it?
- cerebrocerebellum
- coordination of skilled movements, cognitive function, attention, processing of language and emotional control
- damage mainly affects arms/skilled coordinated movements (tremor) and speech
what are the main 5 signs of cerebellar dysfunction?
- ataxia
- dysmetria
- intention tremor
- dysdiadochokinesia
- scanning speech
