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View Article  Paroxysmal dystonia and pathological laughter as a first manifestation of multiple Sclerosis
Paroxysmal dystonia and pathological laughter as a first manifestation of multiple Sclerosis Paroxysmal dystonia is an uncommon but well-established feature of multiple sclerosis (MS). Attacks can occur in established MS and may even   more »
View Article  Immune Police Recognize Good And Bad Guys In The Body

Immune Police Recognize Good And Bad Guys In The Body

 

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Immune system police are as good at recognizing bad guys, ...   more »

View Article  Cerebellum and MS 3 of 3

Cerebellum and MS 3 of 3

 

Phylogenetic and functional divisions

The cerebellum can also be divided in three parts based on both phylogenetic criteria (the evolutionary age of each part) and on functional criteria (the incoming and outgoing connections each part has and the role played in normal cerebellar function). From the phylogenetically oldest to the newest, the three parts are:

Functional denomination (phylogenetic denomination)

Anatomical parts

Role

Vestibulocerebellum (Archicerebellum)

Flocculonodular lobe (and immediately adjacent vermis)

The vestibulocerebellum regulates balance and eye movements. It receives vestibular input from both the semicircular canals and from the vestibular nuclei, and sends fibres back to the medial and lateral vestibular nuclei. It also receives visual input from the superior colliculi and from the visual cortex (the latter via the pontine nuclei, forming a cortico-ponto-cerebellar pathway). Lesions of the vestibulocerebellum cause disturbances of balance and gait.

Spinocerebellum (Paleocerebellum)

Vermis and intermediate parts of the hemispheres ("paravermis")

The spinocerebellum regulates body and limb movements. It receives proprioception input from the dorsal columns of the spinal cord (including the spinocerebellar tract) as well as from the trigeminal nerve, as well as from visual and auditory systems. It sends fibres to deep cerebellar nuclei which in turn project to both the cerebral cortex and the brain stem, thus providing modulation of descending motor systems. The spinocerebellum contains sensory maps as it receives data on the position of various body parts in space: in particular, the vermis receives fibres from the trunk and proximal portions of limbs, while the intermediate parts of the hemispheres receive fibres from the distal portions of limbs. The spinocerebellum is able to elaborate proprioceptive input in order to anticipate the future position of a body part during the course of a movement, in a "feed forward" manner.

Cerebrocerebellum (Neocerebellum)

Lateral parts of the hemispheres

The neocerebellum is involved in planning movement and evaluating sensory information for action. It receives input exclusively from the cerebral cortex (especially the parietal lobe) via the pontine nuclei (forming cortico-ponto-cerebellar pathways), and sends fibres mainly to the ventrolateral thalamus (in turn connected to motor areas of the premotor cortex and primary motor area of the cerebral cortex) and to the red nucleus (in turn connected to the inferior olivary nucleus, which links back to the cerebellar hemispheres). The neocerebellum is involved in planning movement that is about to occur[4] and has purely cognitive functions as well.

 

Much of what is understood about the functions of the cerebellum stems from careful documentation of the effects of focal lesions in human patients who have suffered from injury or disease or through animal lesion research

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Clean the right side of your desk.