NeuroAnatomy - Lecture Nine Objectives - Cerebellum

Question 1

What are the general functions of the cerebellum?

Answer 1

maintain balance, muscle tone/posture, and equilibrium, coordinate movements, motor learning/cognitive-motor learning

Question 2

What is a nickname for the cerebellum and why?

Answer 2

“Little Brain” because it is 10% of the brain’s volume but has 50% of the neurons

Question 3

What is the cerebellum pathway for motor planning/learning?

Answer 3

anterior association area → premotor cortices → pons → cerebellum → thalamus → premotor/primary motor cortices

Question 4

What are the three pairs of nuclei in the cerebellum?

Answer 4

fastigial nuclei(vermis pathways) , interposed nucle(paravermis pathways) , dentate nuclei(lateral hemisphere pathways)

Question 5

What are the two nuclei derived from Interposed Nuclei?

Answer 5

emboliform nuclei and globose nuclei

Question 6

What artery supplies the posterior-inferior cerebellum?

Answer 6

PICA

Question 7

what artery supplies the anterior-middle cerebellum?

Answer 7

AICA

Question 8

what artery supplies the anterior-superior cerebellum?

Answer 8

SCA

Question 9

What are the motor functions of the cerebellum?

Answer 9

balance/vestibulo-ocular control, trunk and proximal limb coordination, distal limb coordination/fine motor movement, and coordination of motor planning for complex movement

Question 10

Which of the motor functions is controlled by the flocculonodular lobe?

Answer 10

balance and vestibulo-ocular control

Question 11

Which of the motor functions is controlled by the vermis?

Answer 11

trunk and proximal limb coordination

Question 12

Which of the motor functions is controlled by the paravermis?

Answer 12

distal limb coordination / fine motor movement

Question 13

Which of the motor functions is controlled by the lateral hemispheres?

Answer 13

coordination of of motor planning for complex movement

Question 14

What is the input, deep cerebellar nuclei, and output for the flocculonodular lobe?

Answer 14

Input: Vestibular Nerve (CN VIII) and vestibular nuclei // Deep Cerebellar Nuclei: None // Output: vestibular nuclei in brainstem

Question 15

What is the input, deep cerebellar nuclei, and output for the vermis?

Answer 15

Input: spinocerebellar tracts from trunks/proximal limbs and vestibular nuclei + visual information

Deep Cerebellar Nuclei: Fastigial Nuclei

Output: info travels to vestibular nuclei down the medial motor tracts in spinal cord

Question 16

What is the input, deep cerebellar nuclei, and output for the paravermis?

Answer 16

Input: spinocerebellar tracts from limbs + motor cortex via pontine nuclei

Deep Cerebellar Nuclei: Interposed nuclei

Output: red nucleus via rubrospinal tract + sends fibers to thalamus and motor cortez via lateral motor tracts

Question 17

What is the input, deep cerebellar nuclei, and output for the lateral hemispheres?

Answer 17

Input: motor association cortex via pontine nuclei

Deep Cerebellar Nuclei: dentate nuclei

Output: thalamus/cortex + red nucleus

Question 18

What type of motor impairments arise from a cerebellar lesion?

Answer 18

hypotonia, disequilibrium, dyssnergia

Question 19

What are the clinical characteristics of dyssynergia: dysarthria and how to exam/test for it?

Answer 19

uncoordinated speech, slurring/slowing of speech, random variation in volume // test = observation of speech

Question 20

What are the clinical characteristics of dyssynergia: dystaxia and how to exam/test for it?

Answer 20

lack of coordination in execusion of learned voluntary movement // test = observation of trunk stability in sitting, standing posture, gait, and ADLs

Question 21

What are the clinical characteristics of dyssynergia: dysmetria and how to exam/test for it?

Answer 21

inability to stop muscular movement at a desired point in space/”overshooting” // test = finger to nose test, point-to-point test, etc

Question 22

What are the clinical characteristics of dyssynergia: intention tremor and how to exam/test for it?

Answer 22

“tremor” that occurs with precise voluntary movement, oscillations occur/increase as patient approches target // test = observe patient perform a “precision task” (pick up a cup, point to a specific spot, observe during finger to nose test, etc)

Question 23

What are the clinical characteristics of dyssynergia: dysdiadochokinesia and how to exam/test for it?

Answer 23

inability to perform rapid alternating/repetitive movement and disruption of timing of movement (initiating and stopping) // test = ask patient to perform rapid alternating movement

Question 24

What are the clinical characteristics of dyssynergia: nystagmus and how to exam/test for it?

Answer 24

ocular dysmetria/spontaneous eye movement // test = observe patient’s eyes when looking around

Question 25

What are the clinical characteristics of dyssynergia: decomposition of movement and how to exam/test for it?

Answer 25

breaking down of smooth muscle activity into jerky awkward fragments // test = observe patient perform specific activity

Question 26

What are the clinical characteristics of dyssynergia: rebound and how to exam/test for it?

Answer 26

inaccurate return extremity to “start position” after forceful resistance // test = “arm pull” or “arm extended” test