Control of Movement 4

Question 1

Name the input nuclei of the basal ganglia

Answer 1

Caudate nucleus

Putamen

Question 2

Name the intrinsic nuclei of the basal ganglia

Answer 2

External segment of globus pallidus
Subthalamic nucleus
Substantia nigra (pars compacta)

Question 3

Name the output nuclei of the basal ganglia

Answer 3

Internal segment of the globus pallidus 
Substantia nigra (pars reticulate)

Question 4

Which NT does the cerebral cortex release to excite the putamen?

Answer 4

Glutamate

Question 5

What effect does the putamen exert on the globus pallidus and how?

Answer 5

Inhibitory via GABA

Question 6

What effect does the medial lobe of GP have on the thalamus normally?

Answer 6

Inhibits activity via GABA

Question 7

What effect does the medial lobe of GP have on the thalamus in the direct pathway?

Answer 7

Increases thalamic activity (GP been inhibited, and it usually inhibits thalamus)

Question 8

What is the overall effect of the direct pathway?

Answer 8

Increase in movement

Question 9

What effect does the putamen have on the lateral lobe of the GP?

Answer 9

Inhibitory via GABA

Question 10

What effect does the lateral lobe of GP usually have on the subthalamic nucleus?

Answer 10

Inhibition via GABA

Question 11

What effect does lateral lobe of GP have on the subthalamic nucleus in the indirect pathway?

Answer 11

As lateral lobe inhibited, (removal of inhibition on subthalamic) increase in activity of subthalamic nucleus

Question 12

What effect does the subthalamic nucleus have on the medial lobe of GP?

Answer 12

Excitation

Question 13

What happens in the indirect pathway regarding the medial lobe of GP?

Answer 13

Increase in activity of medial lobe of GP by subthalamic nucleus which results in increased inhibition of thalamus

Question 14

What is the overall effect of the indirect pathway?

Answer 14

Decrease in movement

Question 15

What effect do D1 receptors have on the basal ganglia?

Answer 15

Enhance direct pathway increasing movement

Question 16

What effect do D2 receptors have on the basal ganglia?

Answer 16

Inhibit indirect pathway increasing movement

Question 17

Where is dopamine released from?

Answer 17

Pars compacta of substantia nigra

Question 18

What are the 4 main features of parkinsonism? (TRAP)

Answer 18

Tremor
Rigidity
Akinesia
Posture

Question 19

Which pathway is affected in Parkinsons?

Answer 19

Direct - hypokinetic

Question 20

What is hemiballismus?

Answer 20

Lesion of subthalamic nucleus resulting in no stimulation of GPi resulting in violent projectile movements

Question 21

Where are lesions that cause chorea?

Answer 21

Putamen

Question 22

Which is the genetic cause of Huntington’s chorea?

Answer 22

Excessive CAG repeats on chromosome 4

Question 23

What is the physiological cause of chorea?

Answer 23

Loss of GABA neurons in putamen that project to GBe (inhibition of indirect pathway)

Question 24

What is athetosis?

Answer 24

Lesion of globus pallidus which causes abnormal movements (hyperkinetic)

Question 25

What causes the pathology in Wilson’s disease?

Answer 25

Accumulation of copper in lentiform nucleus

Question 26

Which basal ganglia structure is affected in Wilson’s disease?

Answer 26

Lentiform nucleus

Question 27

What are the main symptoms of Wilson’s disease?

Answer 27

Dystonia

Tremor

Question 28

What is the name of the malformed protein in Hungtinton’s disease?

Answer 28

Huntingtin

Question 29

What is the physiological cause of Huntington’s disease?

Answer 29

Loss of encephalin and GABA secreting neurons in the neostriatum leading to decrease in indirect pathway

Question 30

What are the features of a basal ganglia lesion?

Answer 30

Contralateral signs
Increased tone
Normal reflexes

Question 31

What is dystonia?

Answer 31

Lesion of lentiform nucleus that causes muscle contraction and abnormal posture