1 / 32

CEREBELLUM

CEREBELLUM. Gross Morphology. Tentorium cerebelli Falx cerebelli. Anatomical Plan I. Left and right hemispheres: Anterior and posterior lobe: Subconscious movements of skeletal muscles Flocculonodular nodes: Concerned with equilibrium Vermis. Anatomical Divisions.

jens
Télécharger la présentation

CEREBELLUM

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. CEREBELLUM

  2. Gross Morphology • Tentorium cerebelli • Falx cerebelli

  3. Anatomical Plan I • Left and right hemispheres: Anterior and posterior lobe: Subconscious movements of skeletal muscles Flocculonodular nodes: Concerned with equilibrium • Vermis

  4. Anatomical Divisions • Cerebellar cortex: Gyri = Folia • Myelinated medulla: Arbor vitae

  5. Cerebellar Peduncles • Inferior (restiform bodies): Connects to medulla • Middle (brachium pontis): Connects to pons • Superior (brachium conjunctivum): Connects to midbrain and thalamus

  6. Nuclei • Intracerebellar (paired): Dentate Emboliform Globose Fastigial • Pontine nuclei (pons): • Inferior olivary nuclei (medulla)

  7. Plan II: Flocculonodular Lobes • Archicerebellum • Vestibulocerebellum • Flocculi separated by nodulus • Functions: Regulation of muscle tone Maintenance of equilibrium (axial musculature) Regulation of head/eye movements

  8. Plan II: Anterior Lobe • Paleocerebellum • Functions: Receives proprioceptive information Regulates muscle tone

  9. Plan II: Posterior Lobe • Neocerebellum • Cerebrocerebellum • Functions: Receives cerebral input via pons Involved in muscle movement Involved in planning and coordination

  10. Anatomical Plan III • Medial (vermal) zone: Fastigial nucleus Part of spinocerebellum • Paramedian (paravermal) zone: Globose and emboliform nuclei Part of spinocerebellum • Lateral (hemispheric) zone: Dentate nucleus Equivalent to neocerebellum (cerebrocerebellum)

  11. Afferent: Mossy Fibers • Via inferior cerebellar peduncles: Dorsal spinocerebellar Reticulocerebellar • Via superior cerebellar peduncles: Ventral spinocerebellar • Via middle cerebellar peduncles: Pontocerebellar

  12. Afferent: Climbing Fibers • Climbing fibers arise from inferior olivary nuclei

  13. Efferent Tracts • All efferent fibers from cortex are from Purkinje cells: • Purkinje cells project to intracerebellar nuclei.

  14. Efferent Tracts • Via inferior cerebellar peduncles: To vestibular nuclei: Cerebellovestibular: From flocculonodular lobe = (vestibulocerebellum) From fastigial nucleus To lateral vestibular nucleus: Cerebellovestibular From anterior vermis (spinocerebellum)

  15. Efferent Tracts • Via inferior cerebellar peduncles: To reticular formations in pons and medulla: Cerebelloreticular tract: From fastigial nucleus

  16. Efferent Tracts • Via superior cerebellar peduncles: To red nucleus (nucleus ruber): Cerebellorubral tract: From dentate, emboliform, and globose nuclei To ventral anterior and ventral lateral thalamic nuclei: Cerebellothalamic tracts: From dentate, emboliform, and globose nuclei

  17. Efferent Tracts • Thalamocortical tracts: To motor cortex Through internal capsule • Corticopontine tracts: To pontine nuclei

  18. Functions • Skeletal muscle coordination • Maintain equilibrium and posture • Synergic control of muscle activity • Kinetic memory?

  19. Cerebellar Cortex: Layers • Molecular layer (outer) • Granular layer (middle) • Purkinje layer (deeper)

  20. Cerebellar Cortex: Cell Types • Stellate cells • Basket cells • Granular cells • Golgi cells • Purkinje cells

  21. Cerebellar Cortex Organization • Climbing and mossy fibers convey excitatory input from spinal cord and brainstem to deep cerebellar nuclei and cortex.

  22. Cerebellar Cortex Organization • Climbing fibers originate from inferior olivary nuclei and are excitatory to deep cerebellar nuclei and Purkinje cells.

  23. Cerebellar Cortex Organization • Mossy fibers originate from spinal cord and other parts of the brain and are excitatory to granular cells.

  24. Granular Cells • Granular cells receive input from mossy fibers: Excitatory input. Collaterals from mossy fibers also to intracerebellar nuclei. • Granular cells project into molecular layer and give off left/right axon collaterals.

  25. Granular Cells • Granular cells are excitatory. • Synapse with: Stellate, Golgi, basket, and Purkinje cells

  26. Other Cortical Cells • Stellate cells synapse with dendritic tree of Purkinje cells (inhibitory). • Basket cells synapse with axon hillock of Purkinje cell (inhibitory). • Golgi cells synapse with cell bodies of granular cells (inhibitory). • Purkinje cells synapse with intracerebellar nuclei (inhibitory).

  27. Cerebellar Cortex • Climbing fibers from inferior olivary nuclei: Synapse with intracerebellar nuclei: Axon collaterals Excitatory Synapse with dendritic tree of Purkinje cells: Excitatory Excitatory burst “cleans” Purkinje cells

  28. Cerebellar Cortex • Only efferents from cerebellar cortex are Purkinje cell axons. • All efferents from cerebellum are from intracerebellar nuclei.

  29. Cerebellar Cortex • Noradrenergic projections from locus ceruleus. • Serotoninergic projections from raphe nuclei.

More Related