Basal Ganglia

Question 1

Which neurotransmitter is primarily inhibitory in the basal ganglia?
a) Dopamine b) GABA c) Glutamate d) Acetylcholine

Answer 1

b) GABA

Question 2

The caudate nucleus and putamen together are called:
a) Lentiform nucleus b) Substantia nigra c) Striatum d) Globus pallidus

Answer 2

c) Striatum

Question 3

The direct pathway of the basal ganglia is primarily responsible for:
a) Inhibiting motor activity b) Amplifying unwanted movements c) Initiating motor movements d) Modulating sensory input

Answer 3

c) Initiating motor movements

Question 4

In the direct pathway, the globus pallidus internus releases less GABA to which structure?
a) Globus pallidus externus b) Subthalamic nucleus c) Thalamus d) Motor cortex

Answer 4

c) Thalamus

Question 5

In the indirect pathway, which structure receives inhibitory input from the striatum?
a) Subthalamic nucleus b) Globus pallidus externus c) Globus pallidus internus d) Thalamus

Answer 5

b) Globus pallidus externus

Question 6

What type of receptor does dopamine bind to in the direct pathway?
a) D2 receptor b) NMDA receptor c) D1 receptor d) GABA receptor

Answer 6

c) D1 receptor

Question 7

Which disease is associated with degeneration of dopaminergic neurons in the substantia nigra?
a) Huntington’s disease b) Parkinson’s disease c) Wilson’s disease d) Extrapyramidal syndrome

Answer 7

b) Parkinson’s disease

Question 8

What is the role of the nigrostriatal pathway? a) Inhibiting both direct and indirect pathways
b) Modulating the direct and indirect pathways c) Amplifying motor activity of unwanted movements only d) Maintaining sensory input to the basal ganglia

Answer 8

b) Modulating the direct and indirect pathways

Question 9

Glutamate is classified as which type of neurotransmitter?
a) Inhibitory b) Excitatory c) Modulatory d) Neuromodulator

Answer 9

b) Excitatory

Question 10

The globus pallidus externus is directly involved in which basal ganglia pathway?
a) Direct pathway b) Indirect pathway c) Nigrostriatal pathway d) Corticospinal tract

Answer 10

b) Indirect pathway

Question 11

Damage to the nigrostriatal pathway is most likely to result in:
a) Increased GABA release from the globus pallidus internus b) Decreased dopamine release to the striatum c) Overstimulation of the subthalamic nucleus d) Excessive activation of D2 receptors

Answer 11

b) Decreased dopamine release to the striatum

Question 12

A lesion in the subthalamic nucleus would likely result in:
a) Decreased activity in the indirect pathway b) Increased activity in the direct pathway c) Decreased glutamate release to the globus pallidus externus d) Increased inhibition of the motor cortex

Answer 12

a) Decreased activity in the indirect pathway

Question 13

A patient presents with hyperkinetic movements. Which of the following pathways is most likely impaired?
a) Direct pathway b) Indirect pathway c) Nigrostriatal pathway d) Corticospinal tract

Answer 13

b) Indirect pathway

Question 14

Which clinical condition is characterized by excessive copper accumulation affecting the basal ganglia?
a) Huntington’s disease b) Parkinson’s disease c) Wilson’s disease d) Rheumatic fever

Answer 14

c) Wilson’s disease

Question 15

If GABA release from the globus pallidus externus is decreased, which structure is disinhibited?
a) Thalamus b) Motor cortex c) Subthalamic nucleus d) Striatum

Answer 15

c) Subthalamic nucleus

Question 16

In Parkinson’s disease, loss of dopaminergic input to the direct pathway leads to:
a) Reduced motor activity b) Increased motor activity c) Hyperactivity of the thalamus d) Disinhibition of the globus pallidus externus

Answer 16

a) Reduced motor activity

Question 17

Which of the following correctly matches the pathway and its effect?
a) Indirect pathway → increases motor activity b) Direct pathway → decreases motor activity c) Nigrostriatal pathway → amplifies motor modulation d) Corticospinal tract → modulates basal ganglia input

Answer 17

c) Nigrostriatal pathway → amplifies motor modulation

Question 18

A mutation causing excessive CAG repeats in the Huntington gene primarily affects:
a) Subthalamic nucleus b) Striatum c) Globus pallidus internus d) Zona reticularis

Answer 18

b) Striatum

Question 19

Excessive glutamate activity in the subthalamic nucleus would result in:
a) Increased motor activity b) Decreased motor activity c) Inhibition of the direct pathway d) Overactivation of D2 receptors

Answer 19

b) Decreased motor activity

Question 20

Activation of D2 receptors in the striatum causes:
a) Increased inhibition of the globus pallidus externus b) Decreased inhibition of the globus pallidus externus c) Increased inhibition of the thalamus d) Decreased motor activity

Answer 20

b) Decreased inhibition of the globus pallidus externus

Question 21

A lesion in the substantia nigra zona compacta would likely cause which of the following effects?
a) Decreased dopamine release to the striatum b) Increased stimulation of the globus pallidus internus c) Reduced motor activity of wanted movements d) All of the above

Answer 21

d) All of the above

Question 22

In Huntington’s disease, the degeneration of striatal neurons primarily affects which pathway?
a) Nigrostriatal pathway b) Direct pathway c) Indirect pathway d) Corticospinal tract

Answer 22

c) Indirect pathway

Question 23

Which neurotransmitter imbalance contributes to hyperkinetic movements in Huntington’s disease?
a) Excess dopamine and decreased GABA b) Decreased dopamine and increased GABA c) Excess glutamate and decreased dopamine d) Excess acetylcholine and decreased GABA

Answer 23

a) Excess dopamine and decreased GABA

Question 24

If the globus pallidus internus releases less GABA, what happens to the thalamus?
a) The thalamus is inhibited b) The thalamus is stimulated c) The thalamus becomes hyperpolarized d) The thalamus receives no input

Answer 24

b) The thalamus is stimulated

Question 25

A drug that increases dopamine activity in the nigrostriatal pathway would have what effect on movement? a) Increased unwanted motor movements b) Increased desired motor movements c) Decreased thalamic stimulation d) Inhibition of the subthalamic nucleus

Answer 25

b) Increased desired motor movements

Question 26

In Parkinson’s disease, degeneration of dopaminergic neurons in the substantia nigra primarily affects which of the following? a) Direct pathway, reducing motor activity b) Indirect pathway, increasing motor activity c) Both pathways equally d) Corticospinal tract, reducing motor activity

Answer 26

a) Direct pathway, reducing motor activity

Question 27

Stimulation of the subthalamic nucleus in the indirect pathway leads to which of the following? a) Increased glutamate release to the globus pallidus internus b) Decreased inhibition of the thalamus c) Increased GABA release to the motor cortex d) Decreased motor activity

Answer 27

d) Decreased motor activity

Question 28

Which of the following correctly describes the function of the indirect pathway? a) Initiates desired motor movements b) Inhibits undesired motor movements c) Modulates sensory input to the motor cortex d) Amplifies input to the corticospinal tract

Answer 28

b) Inhibits undesired motor movements

Question 29

Dopamine binding to D2 receptors in the indirect pathway has what effect? a) Reduces inhibition of the globus pallidus externus b) Increases GABA release from the striatum c) Increases stimulation of the subthalamic nucleus d) Decreases motor activity

Answer 29

a) Reduces inhibition of the globus pallidus externus

Question 30

A lesion in the globus pallidus externus would likely disrupt which pathway? a) Nigrostriatal pathway b) Direct pathway c) Indirect pathway d) Corticospinal tract

Answer 30

c) Indirect pathway

Question 31

Which clinical feature is most likely in a patient with a lesion in the subthalamic nucleus? a) Chorea b) Bradykinesia c) Rigidity d) Hemiballismus

Answer 31

d) Hemiballismus

Question 32

What is the primary role of dopamine in the basal ganglia pathways? a) Stimulates the direct pathway and inhibits the indirect pathway b) Inhibits both direct and indirect pathways c) Only inhibits the indirect pathway d) Only stimulates the direct pathway

Answer 32

a) Stimulates the direct pathway and inhibits the indirect pathway

Question 33

A medication that reduces glutamate activity in the subthalamic nucleus would have what effect? a) Increased motor activity b) Decreased motor activity c) No effect on motor activity d) Increased stimulation of the thalamus

Answer 33

a) Increased motor activity

Question 34

Which of the following is a clinical manifestation of damage to the indirect pathway? a) Hyperkinetic movements b) Resting tremor c) Akinesia d) Rigidity

Answer 34

a) Hyperkinetic movements

Question 35

What is the expected effect of D1 receptor activation in the striatum? a) Increased inhibition of the globus pallidus externus b) Increased inhibition of the globus pallidus internus c) Increased inhibition of the thalamus d) Increased motor activity

Answer 35

d) Increased motor activity

Question 36

A lesion in the globus pallidus internus would most likely result in: a) Increased thalamic stimulation b) Decreased thalamic stimulation c) Increased motor activity d) Both a and c

Answer 36

d) Both a and c

Question 37

Which of the following is a hallmark feature of Parkinson’s disease due to impaired basal ganglia function? a) Akinesia and bradykinesia b) Hyperkinetic movements c) Hemiballismus d) Athetosis

Answer 37

a) Akinesia and bradykinesia

Question 38

In the indirect pathway, what happens if GABA release from the striatum increases? a) Increased inhibition of the globus pallidus externus b) Decreased inhibition of the subthalamic nucleus c) Increased stimulation of the thalamus d) Decreased motor activity

Answer 38

d) Decreased motor activity

Question 39

What is the effect of dopamine depletion on the indirect pathway? a) Increased activity of the subthalamic nucleus b) Increased stimulation of the thalamus c) Decreased GABA release from the striatum d) Decreased inhibition of the globus pallidus internus

Answer 39

a) Increased activity of the subthalamic nucleus

Question 40

Which structure is hyperactive in patients with Parkinson’s disease, leading to reduced motor activity? a) Subthalamic nucleus b) Globus pallidus externus c) Globus pallidus internus d) Motor cortex

Answer 40

a) Subthalamic nucleus