Cerebellum

Question 1

Folia

Answer 1

Fine lines in cerebellum to increase SA

Question 2

3 Peduncles

Answer 2

Superior Cerebellar - efferents to red nucleus, thalamus, etc (has to decussate)
Middle - afferents from pons/cortex, so very big
Inferior - afferents and efferents from vestibular nuclei

Question 3

4 Somatotopic Areas of Cerebellum/Functions

Answer 3

Vermis - middle: proximal extremity and trunk muscles
Intermediate part - distal extremity muscles
Lateral part - motor planning for extremities
Flocculonodular lobe - long thing across: balance and vestibulo-ocular reflexes

Question 4

3.2 Deep Cerebellar Nuclei (and what they receive from)

Answer 4

Dentate nucleus - lateral cerebellar cortex
Interposed nuclei (emboliform and globose nuclei) - intermediate
Fastigial nucleus - vermis and flocculonodular

Question 5

3 Input Tracts to Cerebellum

Answer 5

Spinocerebellum
Cerebrocerebellum
Vestibulocerebellum

Question 6

Spinocerebellum pathway

Answer 6

Does muscles, as well as ipsilateral spinal cord proprioceptive input from inf cerebellar peduncle and double decussated spinal cord proprio via interneurons from sup cerebellar peduncle

Question 7

Cerebrocerebellum pathway

Answer 7

To plan and regulate complex movements, takes contralateral cerebral cortex input via corticopontocerebellar tract

Question 8

Corticopontocerebellar tract

Answer 8

Corticopontine tract to pontine nuclei, decuss as pontocerebellar tract via middle cerebellar peduncle, go through purkinje axons to deep nuclei, then decuss again as dentatothalamic tract via superior cerebellar peduncle, then synapse to thalamocortical tract back to cortex. So decusses twice

Question 9

Vestibulocerebellum

Answer 9

Involved in posture/balance via excitatory mossy fibers acting on cerebellar cortex and deep cerebellar nuclei

Question 10

Climbing Fibers

Answer 10

Form feedback loop from inferior olive to cerebellum to red nucleus back to IO. Act on Purkinje cells and excitatory on deep cerebellar nuclei. Purkinje cell sends negative effects on DCN. DCN is output

Question 11

3 Places DCN Project To (& function)

Answer 11

Red nucleus to inferior olive to cerebellum for feedback
Thalamus (VL) to cortex to coordinate motor
Vestibular nuclei to let it know what you’re planning

Question 12

2 Symptoms of Cerebellar Ataxia

Answer 12

Wide stance gait

Intention tremors

Question 13

Dysdiadochokinesia

Answer 13

Inability to perform rapidly alternating movements

Question 14

Nystagmus

Answer 14

Involuntary eye movement characterized by alternating smooth pursuit in one direction and saccadic movement in other

Question 15

Chiari malformation

Answer 15

Cerebellum pushes through foramen magnum and compresses spinal cord, causing cysts to form (syringmyelina) and cuts off CSF causing hydrocephalus