Term
| What is the function of the cerebellum? |
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Definition
• The cerebellum regulates movement and posture indirectly by adjusting the output of the major descending motor systems of the brain.
• It is important in learning |
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Term
| What is the function of the anterior lobe? |
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Definition
| • Anterior lobe is involved in muscle tone which keeps muscles contracted and ready to react |
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Term
| What is the function of the posterior lobe? |
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Definition
• Posterior lobe is associated with free movement and planning
• Plans every possible movement so that movement is smooth and coordinated
• Gets info from the neocortex and the pontine nuclei |
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Term
| What is the function of the Flocculo-nodular lobe? |
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Definition
• keep the head upright
• Very primitive area
• Gets info from the vestibular nuclei (CN VIII) |
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Term
| Describe the role of the Purkinje Cell in the Cerebellum circuitry. |
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Definition
• Gets input from the spinal cord, other neurons within the cerebellum, and the forebrain
• Large cell body
• Huge flat dendritic tree
• Receives both stimulatory and inhibitory information
• It’s the only output neuron of the cerebellum
• Always releases inhibitory signals
• Gets input from stellate neurons
• It sits in long rows like rows of grape leaves in a vineyard |
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Term
| What are the cells of the Molecular layer? |
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Definition
• Stellate cells
• Basket cells |
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Term
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Definition
• Receive stimulatory input from parallel fibers
• Deliver inhibitory synapse to Purkinje cells
• Located on the distal ends of dendritic tree -> forms synapses on the ends of the dendritic tree
• Receive stimulatory input and deliver inhibitory signals to Purkinje cells (in a sense, they are excitatory because they inhibit the inhibitors) |
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Term
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Definition
• Receive stimulatory input form parallel fibers (neighboring regions)
• Deliver inhibitory synapse to Purkinje cells
• Located on the proximal ends of the dendritic tree and cell body -> more control over Purkinje fibers because they synapse very close to the cell body (very powerful inhibitors)
• Receive stimulatory input and deliver inhibitory signals to Purkinje cells (in a sense, they are excitatory because they inhibit the inhibitors) |
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Term
| Cells of the granule cell layer |
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Definition
• Granule cells
• Golgi cells
• Granule and golgi cells are “working against each other” |
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Term
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Definition
• Spinocerebellar pathway ends with “mossy fibers” -> axons spread out like moss
• Granule cells receive stimulatory input from mossy fibers
• Deliver powerful stimulatory input to Purkinje cells via parallel fibers |
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Term
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Definition
• receive stimulatory input from adjacent Purkinje cells and granule cells
• deliver inhibitory input to granule cells |
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Term
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Definition
| parallel fibers -> go from one Purkinje cell to the next in both directions like telephone wires; if a granule cell is stimulated, it will stimulate a whole row of Purkinje fibers |
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Term
| What happens to the cells of the cerebellum when exposed to alcohol and drugs? |
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Definition
• alcohol and drugs -> Purkinje cells are very sensitive to alcohol and drugs; granule cells seem to die upon contact with alcohol
• BAC of 0.08 is the level of toxicity for these cells
• Granule cells aren’t very good at regenerating -> it is physically impossible for them to regenerate in exactly the same pattern
• Tumors often grow as these cells try to regenerate |
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Definition
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