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Cerebellar system and diseases
Balance & Equilibrium
Coordination of movement
Control of gait, posture (Balance )
Control of muscle tone (Motor control )
Cognitive functions
– Attention
– Emotions
– Language
Motor coordination
 Cerebellum does not initiate movement
 It contributes to coordination, precision, and accurate
 It receives input from sensory systems and from other
parts of the brain and spinal cord,
 It integrates these inputs to tune fine motor activity.
Because of this fine-tuning function,
Cerebellar lesions produce disorders in fine movement,
equilibrium, posture, and motor learning.
4 Cerebellar nuclei& neurons
Basket cells-inhibitory
Stellate cells-inhibitory
Golgi cells-inhibitory
Granule cells-excitatory (Glutamate)
Purkinje cells; inhibitory (GABA)
 Dentate nucleus
 İnterpositus nucleus
 Fastigius nucleus
Intrinsic Fibers
– Mossy fibers
These fibers carry impulses from the inferior
peduncle from spinocerebellar pathways,
olivocerebellar pathways.
– Climbing fibers
They carry impulses from the middle cerebellary
peduncle. They carry impulses from the cortex
and projects to the cortex.
• Flocculo-nodulus ARCHICEREBELLUM –
related with vestibular nuclei
• Anterior lobes-PALEOCEREBELLUMspinocerebellar pathways
• Posterior lobes- NEOCEREBELLUM – cerebellopontin pathways
• Flocculo-nodulus receives special
proprioceptive impulses from the vestibular
nuclei (located in pons and the bulb)
Equilibrium and balance , spatial orientation.
Any lesion will cause ataxia , gait disturbance,
Walking difficulty
• Vermis, The medial zone of the anterior lobes
• It receives proprioceptive input from the
spinocerebellar tract and from visual and
auditory systems.
• It sends fibres to deep cerebellar nuclei that,
in turn, project to both the cerebral cortex and
the brain stem, thus providing modulation of
descending motor systems; POSTURE,
• Posterior lobes receive afferents from cortex
through corticopontine pathways.
• It projects to the cortex via the dentate
nucleus. Its projections are to the cerebral
cortex through nucleus ruber, thalamus.
• In association with the differentiation of
skeletal muscle this part is the largest in
humans.It coordinates skilled movements.
• Many projections (mainly the purkinje cell)
relay on deep cerebellary nuclei (mainly
dentate nuclei) and then projects.
• Contrary, Floculo-nodulus directly projects to
vestibular nuclei.
Clinical manifestations of cerebellar
Muscular coordination
No weakness
Initiation of movement delays.
Relaxing delays.
Contractions are irregular, intermittent.
Speech disturbances
Features with regard to lobes
Posterior lobe
Anterior lobe
Intentional tremor
Loss of ability to gauge
• the distance
• Speed
• Power of movement
The act may be carried out with too little or too
much power.
The act may stop before the goal is reached
or overshoot.
• Disturbance of reciprocal innervationcoordination of agonist-antagonist muscles.
• İmpairment of rapid alternating muscles.
• The body parts may be extended or flexed to
extreme positions as the muscle tonus is
decreased (flask).
Intentional tremor
• Tremor is not observed at rest, but during
reaching a target tremor becomes established.
Diferential diagnosis
• Resting tremor (parkinsonian)
• Postural tremor (essential , drugs)
Speech in cerebellar diseases
• Explosive
• Slurred
• As if drunken
Hereditary cerebellar diseases
• Friedrich ataxia
• Spinocerebellar ataxia’s
Acquired cerebellar diseases
• Vascular (Wallenberg syndrome, SCA infarct)
• Degenerative (multisystem atrophies)
• Demyelinating (Multipl Sclerosis)
• Toxic-metabolic (Alchohol abuse, diphenyl
hidantion chronic use)
• Neoplastic, paraneoplastic (cerebellar neoplasms)