Basal Ganglia

Question 1

What term describes repetitive muscle movements of the face, neck, arms, and legs?

Answer 1

Tardive dyskinesia

Question 2

Basal ganglia control movement on which side of the body?

Answer 2

Basal ganglia receive information from ipsilateral upper motor neurons to modulate movement on the ipsilateral side of the body.

Question 3

What dopamine receptor is inhibitory and stimulates unwanted movement?

Answer 3

D2

Question 4

How does Parkinson’s disease result in decreased movement?

Answer 4

The substantia nigra is degraded, which results in less release of dopamine to affect the basal ganglia

Question 5

What basal ganglia pathway is affected by the D1 receptor?

Answer 5

The direct pathway is stimulated by D1

Question 6

What are the two pathways of the basal ganglia and their functions?

Answer 6

Direct pathway - facilitates movement

Indirect pathway - inhibits unwanted movement

Question 7

Inhibition of the GPi has what effect on movement?

Answer 7

Inhibiting the GPi facilitates wanted movement, whereas, stimulating the GPi causes inhibition of unwanted movement.

Question 8

What are the only structures of the basal ganglia involved in the direct pathway?

Answer 8

The cortex stimulates the striatum to release GABA directly onto the GPi. The GPi then releases less GABA onto the thalamus to facilitate wanted movement.

Question 9

What is akinesia?

Answer 9

Loss of voluntary movement

Question 10

What structures make up the striatum?

Answer 10

Putamen & Caudate Nucleus

Question 11

Huntington’s disease causes excessive movement. How is this?

Answer 11

The striatum is lost so modulation of movement is lost.

Question 12

What fiber collection of the basal ganglia loops around the internal capsule to eventually join the lenticular fasciculus?

Answer 12

Ansa leticularis

Question 13

Dysfunction of the basal ganglia has what effect on movement?

Answer 13

Slowed/diminished movement, involuntary movements, & changes in muscle tone

Question 14

Describe the indirect pathway of the basal ganglia.

Answer 14

The cortex stimulates the striatum to release GABA on the GPe. The GPe releases less GABA onto the subthalamic nucleus causing the release of more glutamate onto the GPi. The GPi, in turn, releases more GABA on the thalamus to prevent unwanted movement.

Question 15

What are the structures of the basal ganglia?

Answer 15

Nucleus accumbens, striatum, globus pallidus, substantia nigra, subthalamic nucleus

Question 16

True/False. The substantia nigra promotes all movement, wanted or unwanted.

Answer 16

True. Dopamine receptors result in stimulation of the direct pathway or inhibition of the indirect pathway.

Question 17

Hemibalism (flailing movement on one side) is an indication of what pathological condition?

Answer 17

Lesion in the subthalamic nuclei on the contralateral side

Question 18

What fibers from the GPi run through the internal capsule?

Answer 18

Lenticular fasciculus

Question 19

What basal ganglia pathway is affected by the D2 receptor?

Answer 19

The indirect pathway is inhibited by D2

Question 20

What is myoclonus?

Answer 20

Quick, involuntary muscle jerks

Question 21

What is chorea?

Answer 21

Involuntary, irregular, unpredictable muscle movements

Question 22

What term describes slowness of movement?

Answer 22

Bradykinesia

Question 23

True/False. The basal ganglia receive motor and sensory information.

Answer 23

False. The basal ganglia receive only motor input in order to plan and control movement.

Question 24

How does the release of GABA on the thalamus by the GPi affect movement?

Answer 24

Secretion of less GABA promotes movement, while more GABA inhibits movement

Question 25

On what side of the body does the basal ganglia control movement?

Answer 25

Contralateral movement

Question 26

What dopamine receptor is excitatory and stimulates wanted movement?

Answer 26

D1