11. Motor Control and Disorders II

Question 1

Which Globus Pallidus region acts as the ‘brakes’ on motor action

Answer 1

Medial GP internal

Question 2

the GP-internal is more active in which basal ganglia movement pathway?

Answer 2

the indirect pathway - suppresses movements

Question 3

This basal ganglia pathway additionally goes through the lateral GP external and subthalamic nucleus

Answer 3

the indirect pathway

Question 4

This basal ganglia movement pathway is excitatory

Answer 4

Direct pathway

Question 5

the indirect and direct pathways occuring in parallel mean:

Answer 5

movements occur at the right order at right time

Question 6

This movement disorder is idiosyncratic (affects everyone differently)

Answer 6

Parkinson’s disease

Question 7

What is the Parkinson’s Mask? What are its consequences

Answer 7

loss of facial expression, can negatively affect communication

Question 8

Which pathways are affected in Parkinson’s and how?

Answer 8

• Both

- reduced dopamine to putamen leads to underactive direct pathway and overactive indirect pathway

Question 9

L-DOPA for parkinson’s can cause what after long periods of time?

Answer 9

dyskinesia - large exhaggerated movements (undesired)

Question 10

How can deep brain stimulation to the STN aid parkinsons?

Answer 10

• more excitation to GPi, so more inhibition to thalamus and M1
• reduces the effect of the indirect pathway (increases activity of this pathway)

Question 11

This motor disease is inherited via an autosomal dominant gene

Answer 11

Huntington’s Disease

Question 12

Main symptom of Huntington’s?

Answer 12

Chorea - uncontrolled movement

Question 13

What is the underlying pathology of Huntington’s?

Answer 13

• death of cells in the caudate and putamen (striatum) that input to the basal ganglia
• defect on gene coding for huntingtin protein

Question 14

Which basal ganglia pathways are affected in huntington’s and how?

Answer 14

• indirect pathway

- underactive: less inhibition of unwanted movement

Question 15

Which syndrome can lead to the presence of simple and complex tics, especially during stress?

Answer 15

Tourette syndrome

Question 16

When might tics be less obvious in Tourette’s?

Answer 16

While the patient is concentrating

Question 17

This basal ganglia condition is more common in boys

Answer 17

Tourette’s syndrome

Question 18

True or false, tourette’s is hereditary

Answer 18

True

Question 19

Which basal ganglia pathway(s) is affected in Tourette’s and how?

Answer 19

• direct pathway

- is overactive

Question 20

What is the underlying pathology of Tourette’s syndrome (hint, opposite to Parkinson’s)?

Answer 20

• too much release of dopamine from substantia nigra

- genetic defect on molecule that is involved in dopamine biosynthesis

Question 21

What is often used as treatment for Tourette syndrome?

Answer 21

• dopamine antagonists

Question 22

Give examples of simple tics

Answer 22

eye blinking, nose twitching

Question 23

Give example of complex tics:

Answer 23

scratching gestures, utterances, swearing

Question 24

Which of the 3 movement disorders links to obsessive compulsive disorders

Answer 24

Tourettes

Question 25

This movement disorder is developmental

Answer 25

Tourette’s

Question 26

Huntington disease is associated with structural brain changes, these are:

Answer 26

Enlarged lateral ventricles due to less brain tissue/degeneration