Neuroanatomy: Cerebellum

Cerebellum function

contract the proper muscle at the appropriate time with the correct amount of force

The embryologic origin of the cerebellum is from the...

rhombic lip

rhombic lip

area of the developing neural tube that is part of the metencephalon that becomes the cerebellum

The cerebellum is part of what region of the brain?

metencephalon

Vermis of cerebellum

the midline strip going down the center of the cerebellum rostral to caudal

What is located on either side of the vermis?

hemispheres of the cerebellum

hemispheres of the cerebellum

located on either side of the vermis

Ridges of the cerebellum are called _______

folia (folium)

Grooves of the cerebellum are called _______

sulci

Two areas of gray matter in the cerebellum

1.) cortical gray matter

2.) subcortical gray matter

White matter of the spinal cord is called...

arbor vitae

arbor vitae

white matter of the cerebellum directly under the cortical gray matter

Three lobes of the cerebellum

1.) rostral lobe

2.) caudal lobe

3.) flocculonodular lobe

Rostral lobe of cerebellum

lobe on the dorsal rostral region

Caudal lobe of cerebellum

lobe on the dorsal caudal region

Flocculonodular lobe

only lobe on the ventral surface

Two named fissures of the cerebellum

1.) Primary fissure

2.) Caudolateral fissure

Primary fissure

separates the rostral and caudal lobes

Caudolateral fissure

separates the flocculonodular and caudal lobes

Cerebellar nuclei

deeply embedded in white matter under the cortex

Three cerebellar nuclei

1.) fastigial

2.) interpositus

3.) dentate

fastigial nucleus

located closest to the midline

interpositus nucleus

located in between the other two nuclei

dentate nucleus

located as the most lateral nucleus

Three phylogenetic developmental terms of the cerebellum

1.) archi

2.) paleo

3.) neo

archi refers to...

oldest/first part that develops

paleo refers to...

something inbetween developmentally

neo refers to...

latest state that develops

Archicerebellum corresponds to what lobe of the cerebellum grossly?

flocculonodular lobe

flocculonodular lobe function

equilibrium and conjugate eye movements

Archicerebellum corresponds to what functional portion of cerebellum?

vestibulo cerebellum

Paleocerebellum corresponds to what lobe of the cerebellum grossly?

rostral lobe

rostral lobe function

muscle tone, posture, and stereotyped (subconscious) movement

Paleocerebellum corresponds to what functional portion of cerebellum?

spinocerebellum

Neocerebellum corresponds to what lobe of the cerebellum grossly?

caudal lobe

caudal lobe function

voluntary planned movement and highly skilled movement

Neocerebellum corresponds to what functional portion of cerebellum?

pontocerebellum

Three layers of the cerebellum histologically

1.) molecular layer

2.) purkinje layer

3.) granular layer

molecular layer

most superficial and few neuron cell bodies; number of synapses and cell processes present

purkinje layer

one cell layer thick and have a characteristic flask shaped appearance with wide dendritic tree; middle histological layer

granular layer

most deep layer full of granular cells that receive and send information through the cerebellar cortex

Three fiber types of the cerebellum

1.) climbing fibers

2.) mossy fibers

3.) parallel fibers

climbing fibers

come from olivary complex in the brain stem and bring info to the purkinje dendrites in the molecular layer

Climbing fibers input comes from the _____________ motor system

extrapyramidal

mossy fibers

have a widespread origin throughout the brain and bring info to the granule cells

Mossy fibers have input from three systems:

1.) pyramidal motor system

2.) spinocerebellar tract (proprioception)

3.) vestibulocerebellar tract (equilibrium)

Parallel fibers

axons coming from granule cells that travel to purkinje cells

Information from all three fibers will synapse on what cells?

purkinje cells

After receiving information from the fibers, the purkinje cell axons travel to...

deep cerebellar nuclei

What effect can purkinje cell axons have on the deep cerebellar nuclei?

turn them off or turn them off

If stimulated, where will the deep cerebellar nuclei send their axons?

upper motor neurons

Cerebellar afferents

information that is being received or sent to some place

Three types of cerebellar afferent information

1.) proprioception

2.) extrapyramidal

3.) pyramidal

For proprioception, information comes from where?

spinocerebellar and vestibulocerebellar tracts

For the extrapyramidal system , information comes from where?

olivocerebellar tract

For the pyramidal system , information comes from where?

pontocerebellar tract

All the afferent information coming into the cerebellum enters through...

the middle or caudal cerebellar peduncles

What type(s) of afferent information goes through the middle cerebellar peduncle?

pyramidal motor system information

What type(s) of afferent information goes through the caudal cerebellar peduncle?

extrapyramidal motor system information and proprioception

Cerebellar efferent information

information that is sent out

All of the efferent information of the cerebellum is sent out of...

purkinje cells

Purkinje cells send information to...

deep cerebellar nuclei

deep cerebellar nuclei send information to...

upper motor nuclei in the brainstem

Fibers for the efferent portion of cerebellar function travel through which cerebellar peduncle to reach the brainstem ?

rostral cerebellar peduncle

The middle and caudal cerebellar peduncles carry _______ information, and the rostral cerebellar peduncle carries ________ information

afferent; efferent

Exception to the idea that middle and caudal peduncles = afferent and rostral peduncles = efferent

ventral spinal cerebellar tract

Is the ventral spinal cerebellar tract afferent or efferent? Which cerebellar peduncle does its fibers pass through?

afferent; rostral cerebellar peduncle

Cerebellar disease has an ___________ function on the body

ipsilateral

Clinical signs of cerebellar disease

1.) dysmetria

2.) lack of coordination

3.) nystagmus, strabismus, and head tilt due to vestibular connections

dysmetria

problems with rate, range, direction, and force of movement