Module 5: Motor Systems II - Basal Ganglia, Subthalamus & Cerebellum

Question 1

Basal ganglia (nuclei) - large masses of gray matter (nuclei) deep within the cerebral hemispheres. These include what 6 components?

Answer 1

1. caudate
2. putamen
3. globus pallidus

Question 2

What is the lenticular nucleus a combination of?

Answer 2

The putamen and globus pallidus

Question 3

What is the function of the basal ganglia?

Answer 3

To modulate voluntary motor activity

Question 4

Together, the putamen and the caudate are referred to as what?

Answer 4

The striatum (it appears striped)

Question 5

Describe the location of the caudate nucleus.

Answer 5

The caudate nucleus is a tadpole-shaped nucleus. The head of the caudate is located in the floor of the lateral ventricle and the body arches over the thalamus in a C shape tapering off into a tail located in the
roof of the inferior horn of the lateral ventricle.

Question 6

Describe the location of the putamen.

Answer 6

The putamen is the most lateral of the basal ganglia and
embryologically is connected to the caudate nucleus.

Question 7

Describe the location of the globus pallidus.

Answer 7

The globus pallidus is medial to the putamen and lateral to
the thalamus.

Question 8

Describe the location of the nucleus accumbens.

Answer 8

Occupies the anterior and inferior part of the striatum
where the head of the caudate and the putamen are continuous with each
other.

Question 9

Describe the location and function of the subthalamic nucleus.

Answer 9

The subthalamic nucleus is a biconvex nucleus that
lies inferior to the thalamus and superior to the tegmentum of the midbrain. It
plays a central role in basal ganglia connectivity and can be described as the
“pacemaker” of the basal ganglia, defining the output rhythm.

Question 10

Describe the location and function of the substantia nigra.

Answer 10

The substantia nigra is located in the rostral midbrain
within the cerebral peduncle, just posterior to the descending motor fibers. It
contains dopaminergic neurons that project to the putamen and caudate
nucleus as well as the subthalamic nucleus.

Question 11

Locate the caudate nucleus and putamen on this coronal brain slice (#6).

Answer 11

caudate - above

putamen - below

Question 12

On this coronal image of the brain, locate the:

1. body of corpus callosum
2. cingulate gyrus
3. cingulum
4. head of caudate nucleus
5. putamen

Answer 12

Question 13

What are the two primary motor control systems?

Answer 13

1. Pyramidal system: represented by the descending corticospinal tract
2. Motor systems other than the corticospinal tract. Includes the basal ganglia and the cerebellum

Question 14

What cortical system controls motor movement?

Answer 14

The upper motor system

Question 15

What systems regulate upper motor neurons?

Answer 15

The basal ganglia and the cerebellum

Question 16

What do the basal ganglia encode for?

Answer 16

• The decision to move
• The direction of movement
• The amplitude of movement
• The motor expression of emotions

Question 17

On this coronal brain section, locate the:

1. caudate nucleus
2. putamen

Answer 17

caudate (medial)

putament (lateral and inferior)

Question 18

Which coronal section has the perfusion areas listed?

Answer 18

8

Question 19

Where is the nucleus accumbens (part of basal ganglia)?

Answer 19

Question 20

Where is the:

1. caudate
2. globus pallidus
3. putamen

Answer 20

1. Caudate nucleus is lateral to the lateral ventricles
2. globus pallidus is medial to the putamen and inferior to the caudate
3. putamen is lateral to the globus pallidus and inferior to the caudate

Question 21

On this coronal slice, where is the:

1. caudate
2. putamen
3. substantia nigra

Answer 21

Question 22

What structures are shown here?

Answer 22

1. caudate nucleus - body (upper)
2. caudate nucleus - tail (lower)