L18: Basal Ganglia - B

Question 1

True or False: The CST is predominately made up of Primary Motor Cortex, however the Premotor Cortex and Supplementary Motor Cortex contribute to the CST

Answer 1

True

Question 2

Which structure is responsible for executing a simple movement?

Which structure is responsible for complex motor responses (e.g planning motor task)?

Answer 2

Primary Motor Cortex = execute simple movement

Premotor Cortex = complex motor responses (planning motor task)

Question 3

True or False: The Supplementary Motor Cortex coordinates movement on both sides, coordinates posture and voluntary movements

Answer 3

True

Question 4

Involuntary movements and altered motor tone suggest damage to the ___ ____

Answer 4

basal ganglia

Question 5

True or False: Basal Ganglia are composed of deep nuclei of telencephalon + diencephalon, as well as the midbrain

Answer 5

True

Question 6

True or False: The Basal Ganglia is involved in coordinating and planning involuntary movements

Answer 6

False - voluntary movements!

Question 7

Overall function of Basal Ganglia?

Answer 7

Smoothly orchestrate motor behavior and regulate AMPLITUDE of movement

Question 8

Label the Corpus Striatum:

Globus Pallidus
Caudate Nucleus
Putamen

Answer 8

Question 9

Which two structures make up the Striatum?

Answer 9

Question 10

Which two structures make up the Lentiform Nucleus?

Answer 10

Question 11

Which three structures make up the Corpus Striatum?

Answer 11

Question 12

Where is the Substantia Nigra located?

Answer 12

Rostral midbrain

Question 13

What does the cortico-basal ganglia-thalamo-cortical loop look like??

Answer 13

Question 14

What are the Interconnections of the Basal Ganglia and which NT are utilized?

Answer 14

Question 15

The basal ganglia sends feedback to the ___ upon request

Answer 15

cortex

Question 16

What do red arrow indicate?

Answer 16

Indicate: always turned on, constitutively active, inhibitory neurons

Question 17

What is the default of this pathway?

Answer 17

Inactivation of thalamus
No muscle movement

Question 18

Information from the cortex to the striatum are known as Corticostriate Inputs. These inputs are excitatory and use ___ as a NT

Answer 18

Glutamate

Question 19

What’s the difference between the Direct and Indirect Pathway?

Answer 19

Direct: FACILITATES flow of movement through thalamus; INCREASES thalamic/cortical activity/movements

Indirect: INHIBITS flow of information through thalamus via subthalamic nucleus; DECREASES thalamic/cortical activity/movement

Question 20

Which pathway is this?

Answer 20

Question 21

Which pathway is this?

Answer 21

Question 22

Where are the spiny neurons located?

Answer 22

Question 23

D1 is activated by ___ and inhibited by _____
A. GABA; Ach
B. Dopamine; GABA
C. Dopamine; Ach
D. Ach; GABA

Answer 23

C. Dopamine; Ach

Question 24

D2 is activated by ___ and inhibited by ____
A. GABA; Ach
B. Dopamine; GABA
C. Dopamine; Ach
D. Ach; GABA

Answer 24

D. Ach; GABA

Question 25

Which structure is responsible for releasing dopamine?

Which structure is responsible for releasing Ach?

Answer 25

DA = Substantia Nigra

Ach = Striatal Interneurons

Question 26

In the direct pathway, the substantia nigra is activated, leading to release of dopamine.
This activates ___ receptor.

Pathway is enhanced, reverberating circuit is maintained…

Answer 26

D1 receptor

Question 27

In the direct pathway, Striatum projects to the Substantia Nigra and inhibits which part of it (pars compacta or pars reticulata).

Which inhibitory NT is involved?

What is the ultimate effect of this?

Answer 27

Pars Reticulata; GABA

• Dopamine is released + excites D1 receptors

Question 28

Which NT excites the direct pathway?

Answer 28

Dopamine

Question 29

True or False: The net effect of dopamine is to increase motor activity and movement

Answer 29

True

Question 30

Loss of dopamine and difficulty in making voluntary movements is associated with which medical condition?

Answer 30

Parkinson’s Disease

Question 31

What is the cause of Parkinson’s Disease?

Answer 31

Loss of dopaminergic inputs to the striatum from the substantia nigra (pars compacta)

Question 32

Which pathway is dominant in Parkinson’s Disease (and, therefore, leads to serious lack of movement)?

Answer 32

Indirect Pathway

Question 33

Which neurotransmitter excites the indirect pathway?

Answer 33

Ach

Question 34

True or False: Ach turns down motor activity and decreases movements

Answer 34

True

Question 35

The cholinergic projections excite the ___ neurons of the indirect pathway, leading to further activation and decreased movement

Answer 35

Striatopallidal neurons

Question 36

Loss of Ach results in…?

Answer 36

Abnormally increased movements

Question 37

Which condition can arise due to loss of cholinergic interneurons in the striatum?

The dominance of which pathway leads to excess, unwanted, and uncontrollable movements?

Answer 37

Chorea; Direct Pathway

Question 38

What are the two main functions of the basal ganglia?

Answer 38

Question 39

True or False: The basal ganglia influences motor movements because they have direct connections to lower motor neurons

Answer 39

False - basal ganglia influences motor movements even though they have NO direct connections to LMN’s

Question 40

True or False: The basal ganglia work with the ipsilateral cortex to influence movement of contralateral side of the body

Answer 40

True

Question 41

Overview??

Answer 41