Cerebellar Disorders Flashcards
What is the nickname for the cerebellum? What % is it of total brain volume? What are the non motor functions of the cerebellum?
“Little Brain”
10
Non motor not well understood but is responsible for shifting attention from one sensory or thought domain to another
What information does the cerebellum modulate?
tone smoothness accuracy coordination postural control
How is the cerebellum involved in motor learning?
It memorizes the small movements that are integrated into a complex activity (driving a stick)
It is active during the acquisition phase of learning
active during cognitive and emotional processes
What supplies blood to the cerebellum?
The PICA - posterior inferior cerebellar artery
AICA- Anterior inferior cerebellar artery
SCA- Superior cerebellar artery
What is the only output from the cerebellar cortex?
Out put comes from the purkinje cells to deep cerebellar nuclei and vestibular nuclei
T/F the hemispheres of the cerebellum ALWAYS control ipsilateral learned/skilled movement and motor planning
True!
Name the nuclei of the cerebellum
Fastigial nucleus- most medial
Globose nuclues + emboliform nucelus = nucleus interpositus
Dentate nucleus - lateral and largest
(most of the output from the cerebellum comes from the nuclei)
Which peduncles of the cerebellum modulate afferent info, efferent info?
Inferior and Middle cerebellar peduncles - modulate afferent
Superior - efferent information to the brainstem and thalamus
What do the archicerebellum, paleocerebellum and neocerebellum correspond to and what is their main source of input?
Archi -vestibulocerebellum = input from semicircular canals, retinal projections- influences eye movement
Paleo = spinocerebellum = input from the spinal cord - limb movement, muscle tone
Neo = cerebrocerebellum = input from the frontal association area for skilled movement
What are the most common pathologies that can affect the cerebellum?
Strokes of the cerebellum and brainstem Spinocerebellar ataxia - 30 types- ped pop Fredrichs ataxia Tumors Trauma metabolic disease vitamin deficiency multiple systems atrophy TBI MS Acute alcoholism - ototoxic
What is archicerebellar syndrome?
lesions result in inability to coordinate head and eye movement, postural sway and impaired equilibrium.
Limbs are ok
Affects vestibular input and postural ton
What is paleocerebellar syndrome?
hypotonia and disruption of rhythmic patterns associate with walking
loss of precision
wide BOS, incoordination
What is neocerebellar syndrome?
The most common type of cerebellar disease
Results in intention tremor, hypotonia, asthenia, asynergia, ataxia
What are long-loop reflex responses?
Balance responses- are modifiable according to what the body needs immediately
if lesioned there is difficulty with adaptation - like standing on a moving bus
However, these individuals rarely fall because they have intersegmental movement and strength with good stepping strategies
What are the clinical signs of cerebellar involvement?
dysmetria dysdiadochokinesia hypotonia interlimb dyscoordination movement decomposition asthenia - general weakness intention tremor dysarthria
