Ataxia Flashcards
Where is the Cerebellum located
- Inferior to cerebral cortex
- Dorsal to pons and medulla
- Joined by peduncles to the pons and medulla
- Two hemispheres
- 3 lobes
What are the Peduncles?
Three pairs of cerebellar peduncles. Tracts of axonal fibres
- Superior, middle and inferior
- Vast majority of fibres passing out of cerebellum go through superior
- Most (Input) efferent fibres go through middle and inferior
- Middle connects cerebellum to pons
- Interior joins spinal chord and medulla
How many cerebellar nuclei and where are they located
3 pairs located in the white matter.
Functions of the Cerebellum
- What are they?
- Coordination of movement and activties. The force and rate and the onset and control during. Postural equilibrium.
- force
- range
- direction
-velocity - rhythm of muscle contraction
- maintains muscle synergies
Damage to the Cerebellum will do what to movement
It will effect the quality of the movement, but don’t prevent movement from happening.
Functional Anatomy-
What are the name of the fissures dividing up the cerebellem?
Primary and postrolateral
What are the three areas of the cerebellem and what do they do?
1- Vestibulocerebellem (Eye movement and balance) Also known as the Arche cerebellum belongs to the floconodular lobe.
2- Spinocerebellum, paleocerebelleum. Central/Rostal lobe. Postural tone and spinal cord
3- Neocerebellem, cerebro-cerebellum-
What do each region of the cerebellem effect?
Vestibulocerebellum- Equibellrium, trunkal attaxia and nystagmus
Spinocerebellum- Hypotonia, neck and head.
Neocerebellum- Dysmetria (lack of smooth movements), rebound phenonmen, attention tremor, disdikionesia, visual persuit
Vestibulocerebellum- What does it effect in more details
Balance- during stance and gait, trunkal ataxia- even falling when sitting, nausea
Eye and head movements- Vestibulo-occulur reflex (VOR)
- cerebellar nystagmus (Fast to the lesion)
Spinocerebellum- What does it effect in more details
Hypotonia- Decrease in excitation of motor neurons, mostly UL.
MOst common in acute lesions
Lost of programmed deceleration
Rebound phenonmenon
Gait ataxia (General deficit- Not relieved when laying down)
Intention tremor-as arm reaches target, goes into shakes
Neocerebellum- What does it effect in more details
Movement decomposition- Difficulty in one smooth movement ‘heaviness’
Dysmetria- wavey movement
Dysdiadochokinesia- flipping hand over turns uncoordinated
Dysarthia, slurred
Problems with visua pursuit
Cardinal sign of cerebellar disease
Ataxia
Ataxia- Three (And one bonus)different types and origins, and how to tell the difference
Sensory- damage to sensory pathways. Worse with eyes closed. Rare dysarthria and nystagmus
Vestibular- Damage to VIII Cochlear nerve. Vertigo, nausea, nystagmus.
Cerebellar- Depends on site, poor coordination, nystagmus. Closing eyes doesn’t make it much worse.
Frontal- scissoring gait
Ataxias can be further divided into Acquired and Inherited. What are the subdivisions of Acquired and examples of each
Symmetrical- Intoxicants, infections, Lyme disease, hypothyrodism
Asymmetrical- Stroke/ TBI, infections- HIV, demylination, tumours, AIDS, cervical spondylosis
