Cerebellum Flashcards
What are the major organizational divisions of the cerebellum?
- vermis (midline)
- hemispheres
- flocculus
Does the cerebellum influence motor activity?
yes, but not directly (outputs have no direct connection to spinal cord)
Which peduncle(s) does incoming information go through?
inferior and middle peduncles
Which peduncle(s) does information exiting the cerebellum go through?
superior peduncle
How many total cerebellar peduncles are there in the body?
6! (superior, inferior, and middle on each hemisphere of the cerebellum)
The primary fissure divides what?
anterior and posterior lobes
The horizontal fissure divides what?
posterior lobe into two parts
What is the flocculonodular lobe thought to be involved with?
balance, as many of its fibers project to the vestibular nucleus
What are the main inputs to the inferior cerebellar peduncle?
fibers from cerebral cortex, which synapse in pontine gray nuclei before traveling through MCP
What are the main inputs to the middle cerebellar peduncle?
vestibular and cochlear nuclei, inferior olive, and dorsal spinocerebellar / cuneocerebellar tracts
Where do Purkinje fibers from vermis project?
fastigial nucleus
Where do Purkinje fibers from paravermal area project?
interposed nucleus
Where do Purkinje fibers from cerebellar hemisphere project?
dentate nucleus
What are the deep cerebellar nuclei?
fastigial nucleus, interposed nucleus (globose-emboliform), dentate nucleus
________ project out via superior cerebellar peduncle.
output fibers of deep nuclei
What are the afferents projecting to the ICP?
-afferents: inferior olivary nucleus, vestibular nuclei, and spinal cord
-efferents: vestibular nuclei from flocculonodular lobe
(remember that IC is predominantly afferent)
What are the afferents projecting to the SCP? What are the efferents?
- ONLY afferent: anterior spinocerebellar tract
- efferents: deep cerebellar nuclei
What are the afferents projecting to the ICP? What are the efferents?
- afferents: cerebral cortex
- no efferents!
Cells that send their axons into the molecular layer as parallel fibers:
granular cells (within granular layer)
Layer of the cerebellum that contains only axons that leave the cerebellar cortex:
Purkinje cell layer
Layer of the cerebellum that is mainly axons and dendrites (no cell bodies):
molecular layer
Which cells are contained within the molecular layer?
basket cells and stellate cells
The vermis affects coordination of which part of the body?
trunk
The cerebellar hemispheres affect coordination of mainly which part of the body?
extremities
