Quiz 5 Cerebellum Flashcards
Cerebellum integrates very rapidly a host of sensory input info. on the momentary status of:
Muscle contraction
joint tension
Visual & auditory input on the equilibrium
Integration allows the cerebellum to aid & influence:
Muscle tone
Posture
Aids in making skilled somatic muscle movements smooth and effective
True or False Input fibers come from ALL CNS levels (M.O., pons, midbrain, diencephalon & telencephalon)
True
T/F Each cerebellar hemisphere influences the ipsilateral side of the body
True
The cerebellum is attached to the Medulla Oblongata via:
Inferior cerebellar peduncle
The cerebellum is attached to the Pons via:
Middle cerebellar peduncle
The cerebellum is attached to the Midbrain via:
Superior cerebellar peduncle
Inferior peduncle:
Afferent fiber dominate (into cerebellum)(Post. spinocerebellar & cuneucerebellar fiers)
Efferent are also present
Middle peduncle:
Afferent fibers only
All fibers going in cerebellum coming from pontine nuclei
Superior peduncle:
Efferent fibers are dominate
Afferent fibers are present (Ant. spinocerebeller fibers)
Which brain tumors are most frequent in male children over female children?
Medulloblastomas
arise in the superior meduallry velum as well as the posterior part of the cerebellar vermis
External subdivisions of cerebellum:
Median: Vermis
Lateral: rt/lt hemisphere
The vermis & the hemispheres are divided into lobes which are named:
Anterior
Posterior
Flocculonodular
White matter collectively is known as:
Corpus Medullare
White matter is primarily made up of 4 different fibers:
- Afferent projection fibers (carrying info. going TOWARDS cerebellum)
- Efferent projection fibers (carrying info. FROM cerebellum
- Commissural fibers (crossing the midline- connecting each side)
- Association fibers (carrying info. from one part of cerebellum to the other)
Most common NEURON cell types:
- Purkinje neurons
- Golgi II neurons
- Stellate neurons
- Basket neurons
- Granular neurons
The 5 neuron cells are arranged into 3 laminae:
Outer: Molecular layer
Middle: Purkinje Cell body layer
Inner: Granular layer
Two types of outside axons bring input in cerebellar cortical laminae:
Mossy fibers
Climbing fibers
Purkinje fibers are the fibers taking messages ____ from the cerebellar cortex
AWAY
- Middle cortical lamina
- Composed of 30 million purkinje neuron cell bodies that reach out into the molecular layer
Purkinje cell layer
________ purkinje axons are the only efferent (outgoing) fibers from the cerebellar cortex. Most of these terminate in the deep central _______ _____. Some bypass to end in Deiters’ portion of the ________ ______.
Myelinated
cerebellar nuclei
Vestibular nucleus
Neurotransmitter released by the Purkinje axon is ________ to its target site.
INHIBITORY (GABA)
- Innermost cortical lamina
- Layer is named for the abundance of small granular neurons that are present.
Granular Layer (lamina)
Granular cell dendrites are ________ by incoming _____ ______. The axon from each granular cell ascends into the molecular layer where it ________ & makes synapse with the spined branches of the purkinje cell dendrites.
Stimulated
Mossy fibers
Bifurcates