Cerebellum And Cerebellar Peduncle

objectives

• To be knowledgeable about aspects of the neurological structures of cerebellum
• Functions
• Causes of cerebellar disorders and effects

Cerebellum

cerebellum is the most identifiable part of the brain due to its highly folded structure.

Folia are complex folds that cover the cerebellum surface.

These are used to create a higher surface area and allow for a large number of nerves in the cerebellum.

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Primary Fissure:
-Located on the superior surface.
-Separates the anterior lobe from the middle(posterior) lobe.
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Horizontal Fissure:
-Located posteriorly within the middle lobe.

Uvulo-nodular Fissure:
-Located on the inferior surface. within the middle lobe.
-Separates the middle lobe from the flocculo-nodular lobe.

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Functions of the Cerebellum:

Located behind the top part of the brain-stem (where the spinal cord meets the brain)

It receives information from the sensory systems, the spinal cord, and other parts of the brain.

It compares intended movements with what is happening with skeletal muscles and regulates voluntary movements such as; posture, balance, speech, spatial perception.

It is also important for learning motor behaviors, and memories.

Damage to the cerebellum, while not causing paralysis or intellectual impairment, might lead to a lack of balance, slower movements, and tremors (shaking). Complex physical tasks would become unsteady and halting.

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cerebelleum

Inputs from local circuit neurons modulate the inhibitory activity of Purkinje cells and occur on both dendritic shafts and the cell body. The most powerful of these local inputs are inhibitory complexes of synapses made around the purkinje cell bodies by basket cells and stellate cells

The molecular layer the Golgi cells. The Golgi cells receive input from the parallel fibers and provide an inhibitory feedback to the cells of origin of the parallel fibers (the granule cells).

Cerebellar Peduncles

Cerebellar Peduncles

• Structure
• Location
• Main Functions

A cerebellar peduncle is a nerve tract that permits communication between the cerebellum and the other parts of the central nervous system.

Three pairs of cerebellar peduncles conduct this communication.
The inferior peduncles bring sensory information about the actual position of body parts such as limbs and joints.

The middle peduncles transmit information about the desired position of these parts.

After integrating and analyzing the information from these two sources, the cerebellum sends impulses through the superior peduncles to the mid-brain.

In response, motor impulses are transmitted down through the pons, medulla oblongata, and spinal cord to stimulate or inhibit skeletal muscles at appropriate times and cause movements of body parts into the desired positions.

This activity makes rapid and complex muscular movements possible.