Lecture 8 Motor control paraloops - Part II

Question 1

What are the significant functions of the cerebellum in motor control?

Answer 1

Body motions
- motor skill learning
- coordination
Eye motions
- complicated!

Question 2

What is huntingtons disease?

Answer 2

general atrophy of the brain, including basal nuclei

Question 3

What basal nucleus is MOST impacted by huntingtons?

Answer 3

caudate

Question 4

Which pathway is lost with huntingtons?

Answer 4

indirect

Question 5

What kind of neuron dies with huntington’s?

Answer 5

D2 medium spiny neuron dies

Question 6

When (what age) does huntington’s disease S&S start?

Answer 6

30-50

Question 7

What is the major motor presentation of huntingtons?

Answer 7

chorea

Question 8

What is the survival after diagnoses?

Answer 8

10-20 years

Question 9

What is hemiballismus?

Answer 9

unilateral subthalamic nucleus is impaired: lost indirect pathway

Question 10

What is increased with hemiballismus?

Answer 10

increased contralateral “unwanted” motor programs: lateralization

Question 11

What is the projection of the FEF to for oculomotor control in basal nuclei system?

Answer 11

caudate body (glutamate)

Question 12

What is the projection of the caudate body to for oculomotor control in the basal nuclei system?

Answer 12

SNpr (GABA)

Question 13

What does the SNpr project to for oculomotor control in the basal nuclei system?

Answer 13

superior colliculus (GABA)

Question 14

What is the total effect of the basal nuclei system in oculomotor control?

Answer 14

disinhibit tonic inhibition of SNpr on superior colliculus nuclei for eye movement

Question 15

What broadmanns area is FEF?

Answer 15

8

Question 16

What level is the posterior parietal cortex of motor control?

Answer 16

level 4

Question 17

Where is the horizontal center?

Answer 17

pontomedullary junction

Question 18

What happens when in early learning stages with basal nuclei?

Answer 18

increased in early learning activities, most active with decision making

Question 19

What happens in late learning phase with basal nuclei?

Answer 19

active only when initiating and ending activities
- CPGs
- basal nuclei quiet in middle

Question 20

What are inputs to the cerebellum?

Answer 20

• mossy fibers from multiple sources
• climbing fibers from the inferior olive

Question 21

Where do mossy fibers go in cerebellum?

Answer 21

to granular layer, then parallel fibers in coronal plane to purkinje dendritic tree

Question 22

Where do climbing fibers go in the cerebellum?

Answer 22

to sagittal plane Purkinje dendritic tree in the molecular layer

Question 23

What does the cerebrocerebellum do in motor control?

Answer 23

PM/M1 from the rostral and caudal VL to the superior colliculus (oculomotor) then passing midline in midbrain in the superior cerebellar peduncle to the deep cerebellar nuclei from the cerebellar cortex

Question 24

Where does the superior cerebellar peduncle project to?

Answer 24

contralat projects to the red nucleus

Question 25

Where does the SCP decussate?

Answer 25

to contralat side in midbrain

Question 26

Where does the SCP go from midbrain to project to?

Answer 26

ventrolateral nucleus caudal and oral part

Question 27

Where does the red nucleus project to?

Answer 27

inferior olivary nucleus to rubroolivary track (learn new skills)

Question 28

What is the inferior olive for?

Answer 28

motor learning

Question 29

What are the 2 parts the red nucleus projects to?

Answer 29

inferior olive and cerebrocerebellum

Question 30

What does new motor/general skills?

Answer 30

principle (inferior) olivary nucleus

Question 31

What is most medial zone in the spinocerebellum?

Answer 31

vermal zone

Question 32

What does the vermal zone project neurons to?

Answer 32

fastigial nucleus to SCAP, cross over in midbrain and project to thalamus (VL) and hypothalamus

Question 33

What tract does the vermal zone go down?

Answer 33

corticospinal tract, cross over at the end of the medulla oblongata or pyramid

Question 34

What does the fastigial nucleus project to?

Answer 34

lVst and mVST

Question 35

What zone of the spinocerebellum is more lateral?

Answer 35

intermediate zone

Question 36

What is the pathway of the intermediate zone?

Answer 36

Purkinje cells project to interposed nucleus to SCP, decussate in midbrain, project to red nucleus to cerebral cortex to integrate in M1

Question 37

What does the rubrospinal tract project to?

Answer 37

red nucleus cross over back to where it started, cerebellar IX

Question 38

What is in the nodulus?

Answer 38

fastigial nucleus

Question 39

Where does the fastigial nucleus project to and control?

Answer 39

- to the cerebral cortex - to the medial vestibular nucleus

Question 40

What is the flocculus projecting to?

Answer 40

lateral vestibular nucleus

Question 41

What is lobule X?

Answer 41

nodulus and dlocculus

Question 42

What is the closed loop in coordination for?

Answer 42

- slow movement: postural control - new skill learning: trial and errors

Question 43

What does slow movement for postural control?

Answer 43

SR slow twitch fatigue resistant fibers

Question 44

What is closed loop?

Answer 44

sensory in and response out

Question 45

What is a feedforward control system for an open loop?

Answer 45

- learned skills - fast movements: saccades of the eyes (unique SR fibers)

Question 46

What is an open loop?

Answer 46

the decision from CNS gets out as motor

Question 47

What happens with muscle activation with a nORMAL cerebellum?

Answer 47

- antagonists slightly lag - similar forces - braking the agonists correctly

Question 48

What happens with intention tremor with a conpromised cerebellum?

Answer 48

- antagonists lagging obviously - stringer forces - agonists need to contract again - intention tremor induced

Question 49

Why is intention tremor different from dysmetria?

Answer 49

- intention tremor has direction everywhere b/c of antagonist muscle kicking in - dysmetria has right direction but too much or too little force

Question 50

With a prism that deflects light to the right. when dart throwing at the beginning its affected but adapted very fast in normal subjects. Normal people can learn with the prism and revert quickly after removing glasses. T/F

Answer 50

True

Question 51

when patients with a cerebellar injury use the prism glasses, what happens?

Answer 51

no adaptation, perform the motion learned in the past - no trend of learning with a prism on

Question 52

How does cross-talking happen with the two paralooops?

Answer 52

reciprocal projections: retrograde tracing

Question 53

When rabies is injected in the striatum, where does it project?

Answer 53

projects to the thalamus, tracing to the dentate nucleus

Question 54

When rabies is injected into the cerebellar cortex, where does it project?

Answer 54

to the pontine nucleus, tracing to the subthalamic nucleus