Basal Ganglia

Question 1

Which of the following white matter tracts is immediately posterior to the STN?

Answer 1

Medial lemniscus

Question 2

Which of the following structures lies immediately inferior to the STN

Answer 2

*Substantia nigra

Question 3

Which of the following structures lies immediately inferior to the GPI?

Answer 3

Optic tract

Question 4

Which of the following structures has a direct inhibitory effect on the thalamus?

Answer 4

Globus pallidus interna (and SN pars reticulata)

Question 5

Which of the following provides the primary afferent input to the putamen?

Answer 5

?? Substantia nigra

Question 6

Which of the following provides the major input to the neostriatum (caudate nucleus and putamen)?

Answer 6

Cortex (cortico-striatal pathways)

Question 7

Which of the following neurotransmitters is released by neurons located in the STN?

Answer 7

Glutamate

Question 8

Which of the following motor circuit structures receives the greatest innervation from the ascending mesostriatal dopamine fibers?

Answer 8

Putamen (corticosubcortical re-entrant circuit)

Question 9

Which of the following best describes the activity of the globus pallidus internus?

Answer 9

? Suppressing unwanted movements (inhibitory input to thalamus)

Question 10

The stria medullaris thalami connects which of the following two limbic structures?

Answer 10

?Anterior thalamic nuclei to the habenula

Question 11

The motor dysfunction that characterizes hemiballismus is most likely caused by the loss of which of the following?

Answer 11

STN (glutamate projections to GPi)

Question 12

The major fibers from the globus pallidus project directly to the…

Answer 12

VA/VL thalamus

Question 13

The major output of the caudate/putamen is to …

Answer 13

GPi

Question 14

The major connection of the STN is with the

Answer 14

GPi

Question 15

The internal arcuate fibers project to which of the following structures?

Answer 15

Become the medial lemniscus and project to the VPL of the thalamus

Question 16

The GP projects directly to the

Answer 16

VA and VL nuclei of the thalamus

Question 17

The external capsule is located between which of the following?

Answer 17

Putamen and claustrum

Question 18

The efferent fibers of the GPi predominantly project to which of the following?

Answer 18

VA and VL nuclei of the thalamus

Question 19

The basal ganglia project directly to which of the following?

Answer 19

Thalamus (ultimately cortex)

Question 20

The autopsy specimen shown came from the pons of a patient who most likely suffered from which of the following?

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Answer 20

Transtentorial herniation (duret hemorrhage)

Question 21

Stimulation of the striatal pathway that inhibits the internal segment of the globus pallidus results in

Answer 21

Decreased inhibition of VA/VL leads to disinhibition… increased motor movement (basic function of direct pathway)

Question 22

Pinprick stimulation of the mid-face results in primary sensory activation of which of the following thalamic nuclei?

Answer 22

VPM (ventral posteromedial nucleus)

Question 23

Neurons in the pars reticulata of the substantia nigra send fibers primarily to which of the following structures?

Answer 23

Thalamus

Question 24

Most efferent fibers from the globus pallidus go to the

Answer 24

Thalamus

Question 25

Most efferent fibers from the caudate nucleus project to the

Answer 25

SNr, GPi

Question 26

In a patient who has had chorea, examination of the brain often reveals cell loss and a decrease in GABA in the ...

Answer 26

Striatum (putamen, caudate), GPi

Question 27

Excitation of putaminal neurons in the nigrostriatal pathway occurs following synaptic release of ...

Answer 27

Dopamine

Question 28

Dopamine is produced by enzymatic action on which of the following substrates in the basal ganglia?

Answer 28

Tyrosine (enzyme tyrosine hydroxylase)

Question 29

Cells in the zona compacta of the substantia nigra project to ...

Answer 29

Striatum (caudate and putamen)

Question 30

A patient has a tremor in his hand at rest that improves when he picks up a cup of coffee. This pathology originates in which of the following structures?

Answer 30

Basal Ganglia (SN pars compacta)

Question 31

A lesion of the STN is most likely to produce contralateral ...

Answer 31

Hemiballismus

Question 32

A 55 year old woman with PD and severe dyskinesias undergoes implantation of a DBS electrode into the GPi. Upon activation, which of the following adverse effects would indicate that the electrode has been placed too deep?

Answer 32

Contralateral phosphenes, visual changes (optic tract)

Question 33

Which of the following parts of the basal ganglia can be seen in the anterior horn of the lateral ventricle

Answer 33

Caudate nucleus

Question 34

Facial recognition is most closely associated with which of the following cortical areas?

Answer 34

Fusiform gyrus

Question 35

The major efferents from the basal ganglia to the thalamus and brain stem originate in which of the following?

Answer 35

? GPi