Cerebellum Flashcards
What are the roles of the cerebellum?
- Coordination of limb, trunk, and oculomotor
- Balance and equilibrium
- Muscle tone
- Motor control
- Motor learning
Describe the location of the cerebellum.
Located in the posterior fossa. Dorsal to midbrain.
What separates the anterior and posterior lobes of the cerebellum?
Primary fissure
What are folia of the cerebellum?
The little ridges on the surface of cerebellum.
What does the posterolateral fissure seperate?
The flocculonodular lobe and the posterior lobe.
What two components make up the flocculonodular lobe.
The flocculus and the nodulus
What does the superior cerebellar peduncle connect and what type of information travels through it?
- Connects the midbrain and the cerebellum.
- Primarily efferent information, but a few afferent.
What does the middle cerebellar peduncle connect and what type of information travels through it?
- Connects the pons to the cerebellum.
- Carries afferent fibers only.
What does the inferior cerebellar peduncle connect and what type of information travels through it?
- Connects the medulla and the cerebellum.
- Afferent and efferent fibers.
What is a defining feature of the superior cerebellar peduncle?
It decussates in caudal midbrain at level of interior colliculi.
What are the 3 different regions of the cerebellum?
- Cerebrocerebellum
- Spinocerebellum
- Vestibulocerebellum
Describe the cerebrocerebellum region.
- It carries input to/form cortex.
- Involved in planning and initiation of movement.
Describe the spinocerebellum region.
- Carries input to/from spinal cord.
- Vermis = trunk movement; posture, proximal limb movement, eye movement
- Intermediate zone = extremity movement; integrates input about appendicular limb position and somatosensory input.
Describe the vestibulocerebellum region.
- Carries input to/from vestibular labyrinth
- Maintenance of equilibrium, balance and posture, vestibulo-ocular control.
What is the cerebellums main function for motor function?
It provides modulatory (inhibitory) effects on motor function.
What type of cells provide major output of the cerebellum?
Purkinje cells.
What are the 2 origins of input for the cerebellum?
- Pontocerebellar fibers
2. Olivocerebellar fibers
Where do the pontocerebellar fibers originate from and what is the function of these fibers?
- From the pontine nuclei.
- Involved in planning and control of precise dexterous movements of the extremities.
- Largest cortical contributors: PrimC, PriSC, visual cortex
Where do the olivocerebellar fibers originate from and what is the function of these fibers?
- From inferoir olivary complex.
- Involved in motor learning and motor memory processes.
What are 4 different spinocerebellar pathways that relay cerebellar input?
- Dorsal Spinocerebellar tract
- Cuneocerebellar tract
- Ventral spinocerebellar tract
- Rostral spinocerebellar tract
What type of input does the dorsal spinocerebellar tract provide to the cerebellum?
Afferent info about LE limb movement.
- Is subconscious perception from intrafusal and joint receptors.
What type of input does the cuneocerebellar tract provide to the cerebellum?
Afferent info about UE/neck limb movements.
- Is subconscious perception from intrafusal and joint receptors.
What type of input does the ventral spinocerebellar tract provide to the cerebellum?
Afferent info about activity of LE spinal cord interneurons from intrafusal fibers and GTOs.
What type of input does the rostral spinocerebellar tract provide to the cerebellum?
Afferent info about activity of UE/neck spinal cord interneurons from intrafusal fibers and GTOs.
Describe the somatotopic organization of the anterior lobe of the cerebellum going from rostral to caudal.
Leg –> arm –> head
Describe the somatotopic organization of the posterior lobe of the cerebellum going from rostral to caudal.
Head –> arm –> leg
What are the 2 structures that all output from the cerebellum travel through?
- Deep cerebellar nuclei
- Dentate
- Emboliform
- Globose
- Fastigial - Vestibular nuclei
Where do the dentate nuclei receive projections of information from?
Receive projections from lateral cerebellar hemispheres about motor planning.
What is the name for the emboliform and globose nuclei?
Interposed nuclei
Where do the interposed nuclei receive projections of information from?
Receive projections from intermediate cerebellar hemispheres about input for the extremity movement.
Where do the fastigial nuclei receive projections of information from?
Receive projections from vermis and part of flocculonodular lobe.
Where do the vestibular nuclei receive projections of information from?
Receive projections from inferior vermis and majority of flocculonodular node.
What type of information does the cerebrocerebellum output pathways convey?
Motor planning and motor initiation of limbs.
What type of information from the spinocerebellum (vermis region) output pathways convey?
Posture, postural limb movement, and eye movement.
What type of information from the spinocerebellum (intermediate zone region) output pathways convey?
Integrates input about appendicular limb position and somatosensory input.
What region of the cerebellum does the PICA supply?
Anterior lobe, superior vermis, superior intermediate zone, and small part of lateral hemisphere.
What region of the cerebellum does the AICA supply?
Tippy top point of lateral hemisphere/posterior lobe, all the peduncles, flocculus, partial tonsil, and posterio-lateral fissure
What region of the cerebellum does the SCA supply?
Posterior lobe, inferior vermis, nodulus, and partial tonsil.
