Module 8 Flashcards
Based on the tentorium, the diencephalon and midbrain are where?
Diencephalon :supratentorial
Midbrain: infratentorial
Name the roof of the cerebellum
Tentorium
Which fossa does the cerebellum rest in?
Posterior
What makes the roof of the brainstem?
The cerebellum
What is the major role of the cerebellum?
Grand coordinator of movement
What is the cerebellum responsible for?
Motor coordination
Muscle tone
Balance
What type of input does the cerebellum process?
Processes unconscious sensory input related to ongoing motor activity
Where does the input come from that the cerebellum processes?
Vestibular system
Muscle receptors (stretch and tension within the muscle)
Primary auditory/visual receptors
General sensors in head and body
What are the three major gross anatomy structures of the cerebellum?
Cortex
White matter
Deep nuclei
Name the 3 layers of the cortex
Molecular
Purkinje
Granular
Which layer of cortex is different from the rest?
The granular
It’s the only excitatory layer
What type of fiber pathways does the white matter core have?
Projecting TO and FROM the cerebellum
How thick is the cortex of the cerebellum?
3-5 mm
Where are the deep nuclei located?
Inside of the white matter
Name the 4 deep nuclei
Dentate
Fastigial
Globose
Emboliform
What three cerebellar peduncles connect the cerebellum to the brainstem?
Superior
Middle
Inferior
What type of nucleus does the globose and emboliform make?
Interposed nucleus
What does the superior peduncle do?
Connects cerebellum to midbrain
Efferent fibers FROM cerebellum GO TO BS and THALAMUS
What does the middle peduncle do?
Connect cerebellum WITH pons
afferent fiber FROM pons TO cerebellum
What does the inferior peduncle do?
Connects cerebellum WITH medulla
afferent AND efferent fibers TO/FROM cerebellum
Does the cerebellum initiate movement?
NO
Which pathways control joint position, muscle contraction and tone? And how does it enter the cerebellum?
Spinocerebellar pathway
ENTERS through superior and inferior peduncle
Which pathway controls the body’s balance/equilibrium? How does it enter the cerebellum?
Vestibulocerebellar
ENTERS through inferior peduncle
Which pathway controls the motor commands/ information to muscles? How does it enter?
Corticopontocerebellar
ENTERS through middle peduncle
True/False: does the feedback mechanism involve the deep nuclei?
TRUE
How are the hemispheres organized?
Longitudinally
Name the two hemispheres and the middle structure
Vermis
Lateral (2)
How many lobes are in each hemisphere? How are they organized?
3
Horizontally
How many zone relate to the deep nuclei?
How are they organized?
3
Mediolateral
What does the vermis (midline structure) deal with?
Controlling muscles of axial body
Shoulders
Neck
Trunk
Hips
What are the sections of the Inferior vermis?
Nodule
Uvulus
Pyramid
Tuber
What do the lateral hemisphere have reciprocal connections to?
Motor association area (4/6)
Somasensory areas (3-1-2/ 5)
Via the corticopontine
Name the 3 lobes of the lateral hemispheres
Flocculonodular (inferior lobe)
Middle lobe
Anterior lobe
Which fissure divides the flocculus from the middle lobe?
Posterolateral fissure
What are two names for the Flocculonodular lobe?
Archicerebellum
Vestibulocerebellum
What is the role of the archicerebellum?
Regulates muscle tone, posture and balance/control of eye movements
Which two parts of the inferior vermis are in the vestibulocerebellum?
Uvula
Nodular
What are the other two names for the anterior lobe?
Paleocerebellum
Spinocerebellum
Which fissure divides the anterior and middle lobes?
Primary fissure
What is the function of the paleocerebellum?
Regulates muscle tone
INPUT from head, face and limbs
What are the two names for the middle lobe?
Neocerebellum
Pontocerebellum
What is the role of the middle lobe?
Motor coordination
Voluntary muscle activity (planning)
RECIPROCAL contralateral connections
Name the 3 zones
Median zone
Intermediate
Lateral
What do all of the zones have?
(HINT) structures of the cerebellum
Cortex
White matter
Deep nuclei
Which deep nuclei are in the median zone aka vermal zone?
What is the vermal zones role?
Fastigial nucleus which OUTPUTS to LMN axial body
Role in movements of axial body
Which deep nuclei are in the intermediate aka the paramedian zone?
Interposed nuclei (globose + emboliform)
What is the function of the paramedian zone?
Controls muscle contractions in distal portions (upper/lower) limbs
Which deep nuclei are in the hemispheric zone?
Dentate
What is the function of the hemisphere zone?
Coordination of sequential movements, motor sequences, learning of complex motor sequences
Does the cerebellum have a topographical representation?
Yes!!
Name the two types of cerebellar homunculus?
Axial body parts :vermis
Limbs and face: intermediate
Are there more afferent neurons or efferent neurons?
Afferents
40:1
Name the two types of afferent neurons in the cerebellum?
Climbing
Mossy
What do the climbing afferent a do?
Excitatory input to purkinje cells
What do the mossy afferents do?
Excitatory input to granule cells
Where do the climbing afferent originate from?
Inferior olives
Where do the mossy afferent originate?
Everywhere but the olivary
How does the input from stretch and general sensory receptors reach the cerebellum?
Inferior peduncle
How does the input from the cerebral cortex enter the cerebellum?
Through the middle peduncle
How does the input pathways from the spine enter the cerebellum?
Through the superior peduncle
CARRY proprioceptive info from the body
How is OUTPUT given FROM the cerebellum?
Superior peduncle
Inferior peduncle
Are output pathways direct?
No! Output is ALWAYS INDIRECT
Where does output from the cerebellum go?
To the VLN of Thalamus then to other parts of the brain
What two important structures do the cerebellum interconnect with?
Motor cortex and basal ganglia
What happens if we have damage to the cerebellum?
Weakness in muscle tone
Impaired coordination & balance
