Cerebellum A/P Flashcards
Generally describe the structure and location of the cerebellum
The cerebellum is a “leafy” structure that is found behind (dorsal to) the pons and medulla. It’s found in between the cerebral cortex and the spinal cord.
Describe the function of the cerebellum.
Coordination of movement, planning and execution of movement, maintenance of posture and coordination of head and eye movement. Basically integrates sensory information from the spinal cord, motor information from the cerebral cortex and balance information from the vestibular system.
What are the two motor control centers of the CNS?
Cerebellum and the Basal Ganglia.
What is the midline of the cerebellum called?
It’s called the “Vermis,” which has the superior and inferior vermis component. Superior vermis in anterior lobe, inferior vermis in posterior
Describe the 3 sections of the cerebellum.
The vermis (superior and inferior) is the center of the cerebellum, adjacent to that in either side is called the paravermal or intermediate hemisphere, and lateral to that is the lateral hemisphere (which dominates most of the size of the cerebellum).
What is the “fluconodular lobe?”
It is the thin middle horizontal slice of the cerebellum that runs all the way through the lateral hemisphere, the intermediate hemisphere and the vermis.
What are the 3 lobes of the cerebellum?
Anterior, posterior and floculonodular lobes.
Where are both the cerebellum and pons derived from?
Derived from the “Metencephalon.”
What separates the cerebellum and the dorsal aspect of the pons?
The 4th ventricle.
What can be found inside the cerebellar cortex?
It has multiple parallel folds that has “maps” of the skeletal muscles of the body.
What is the function of the vermis?
Controls the axial (trunk) and proximal musculature of the limbs.
What is the function of the paravermal or intermediate hemisphere? (of cerebellum)
Control of the distal musculture.
What is the function of the lateral hemispheres of the cerebellum?
It is involved in motor planning, which mainly involves the distal musculature.
What is the function of the flocculonodular lobe?
It’s function is to control balance, smooth execution of movements, and eye movement.
Generally, what can we say that the vermis and the intermediate hemispheres of the cerebellum doing?
It is control ALL motor executions of the entire body regardless of being axial or limb located.
Major input TO the cerebellum comes from where?
It comes from the spinal cord inputs (from golgi tendons and muscle spindle) and then up to the middle and inferior cerebellar peduncle, which relays information into the cerebellum.
Major input FROM the cerebellum goes where?
It goes out through the superior cerebellar peduncle.
Where is the lateral hemisphere of the cerebellum getting its input from? What’s it involved with?
Since it is involved with motor planning and coordination, much of its input comes from the cerebral motor cortex (indirectly via the cortical spinal tract), and also the inferior olivary nucleus.
What is the inferior olivary nucleus’ role?
Acts as an “error detector,” meaning that it projects axons into the cerebellum and influences the cerebellar neurons to change how a movement is performed in the future (in a way to correct a previously “wrong” movement?)
Where is the input of the flocculonodular lobe coming from?
Since it is involved in balance and eye movements it makes sense that the input comes from the vestibular nuclei (CN 8).
Where are the inferior cerebellar peduncles coming from and what does it do?
It arises from the medulla and carries information from the spinal cord and olive into the cerebellum.
Where are the middle cerebellar peduncles coming from and what does it do?
Coming from the motor cortex into the cerebellum (thus, they are affarent pathways) and it simply relays the information from the motor cortex to the cerebellum.
What is the purpose of the superior cerebellar peduncle?
Takes information from the cerebellum out, this is the only way information from the cerebellum leaves, wheres the MCP and ICP delivers information TO the cerebellum.
What are the 3 layers of the cerebellar cortex?
Molecular layer, purkinje layer, and granule cell layer.
What is the outer most layer of the cerebellar cortex called and what does it do?
Outer most layer is called the “Molecular layer,” largely acellular with a lot of parallel fibers (axons of the granule cells). It also has baskets and stellate cells, and the dendric tree of the purkinje cells extend into this layer.
