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Flashcards in Basal ganglia and cerebellum Deck (21)
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What compoents are part of the basal ganglia?

Caudate nucleus

Lentiform nucleus (putamen + external globus pallidus)

Subthalamic nucleus

Substantia nigra

Ventral pallidum,


nucleus accumbens,

nucleus basalis of Meynert


What is the striatum?

The lentiform nucleus plus caudate


What is the function of the basal ganglia?

Elaborating associated movements (e.g. swinging arms when walking; changing facial expression to match emotions)

Moderating and coordinating movement (suppressing unwanted movements)

Performing movements in order


What are the signs and symptoms of parkinsons?

Tremor at rest "pin rolling tremor" in the hand that eventually spreads to the rest of the body

Akinesia - difficulty in the initiation of movements because cannot initiate movements internally

Reduced muscular power

camptocormia (kyphosis)


Hypomimic face - absence of movements that normally aniamate the face

Unbalanced, often pass from walking to running pace


What is the neuropathology of Parkinsons?

Classically the primary pathology involves the neurodegeneration of the dopaminergic neurons that originate in the substantia nigra and project to the striatum


What causes huntingtons?

Chromosome 4, autosomal dominant

CAG repeat (over 35 is diagnostic)


What is huntingtons?

Genetic neurodegenerative disorder

Degeneration of GABAergic neurons in the striatum, caudate and then putamen


What are the motor signs of Huntingtons?

Choreic movements (Chorea)
rapid jerky involuntary movements of the body; hands and face affected first; then legs and rest of body

Speech impairment

Difficulty swallowing
Unsteady gait

Later stages, cognitive decline and dementia


What are the main divisions of the cerebellum?

Vestibulocerebellum (transverse, inferior, antierior)

Spinocerebellum (londitudinal, medial)

Cerebrocerebellum (longditudinal, lateral)


What is the function of the Vestibulocerebellum?

Regulation of gait, posture and equilibrium

Coordination of head movements with eye movements


What is the function of the Spinocerebellum

Coordination of speech

Adjustment of muscle tone

Coordination of limb movements


What is the function of the Cerebrocerebellum

Coordination of skilled movements

Cognitive function,


processing of language

Emotional control


What are the signs of of vestibulocerebellar syndrome?

gait ataxia and tendency to fall (even when patient sitting and eyes open)


What is the most common cause of vestibulocerebellar syndrome?

Damage usually caused by a tumour


What is the most common cause of Spinocerebellar syndrome?

Damage due to degeneration and atrophy associated with chronic alcoholism


What are the signs of of spinocerebellar syndrome?

affects mainly legs, causes abnormal gait and stance (wide-based)


What are the signs of of cerebrocerebellar syndrome?

Damage affects mainly arms/skilled coordinated movements (tremor) and speech


What are the main signs of cerebellar dysfunction?

General impairments in movement coordination and accuracy. Disturbances of posture or gait: wide-based, staggering (“drunken”) gait

Inappropriate force and distance for target-directed movements (knocking over a cup rather than grabbing it)

Intention tremor
Increasingly oscillatory trajectory of a limb in a target-directed movement (nose-finger tracking)

Inability to perform rapidly alternating movements, (rapidly pronating and supinating hands and forearms)

Scanning speech
Staccato, due to impaired coordination of speech muscles


Define ataxia

General impairments in movement coordination and accuracy. Disturbances of posture or gait: wide-based, staggering (“drunken”) gait


What are the inputs to the cerebellum?

Inferior olive projects to Purkinje cells via climbing fibres

All other input to granule cells via mossy fibres and then onwards via parallel fibres


Where do the Cerebellar inputs synapse?

Collatereal branches of both climbing and mossy fibres synapse on deep cerebellar nuclei