Basal Ganglia

Question 1

Which component is necessary for representations of the actual position of the body segments?

Answer 1

Somatosensory system

Question 2

Which component is necessary for representations of the desired position of the body segments in time?

Answer 2

Pre-motor cortex

Question 3

Which system allows you to learn to do complicated movements?

Answer 3

Cerebellum

Question 4

Which system is responsible for reinforcement learning?

Answer 4

Basal Ganglia

Question 5

Which area is also known as the execution system?

Answer 5

Pre motor cortex

Question 6

Where is the homonculus map generally located?

Answer 6

The motor cortex

Question 7

Which area does the planning?

Answer 7

Pre-motor cortex

Question 8

Damage to the pre-motor cortex leads to… (2 things)

Answer 8

Complex motor coordination defecits,

and possibly anogsonosia (loss of awareness)

Question 9

Which area is associated with guidance of movement?

Answer 9

Posterior parietal cortex (PPC)

Question 10

The basal ganglia is made up of what 5 areas?

Answer 10

1. Caudate nucleus
2. Putamen
3. Globus pallidus
4. Subthalamic nucleus
5. Substantia nigra

Question 11

Which 2 parts make up the striatum?

Answer 11

1. Caudate nucleus

2. Putamen

Question 12

What is the main input area of the Basal ganglia?

Answer 12

Striatum

Question 13

Output is relayed by which part of the Basal ganglia?

Answer 13

The Globus pallidus (internal and external segments)

Question 14

Where does information go from the Globus pallidus?

Answer 14

Thalamus

Question 15

What is the main function of the Basal ganglia?

Answer 15

To receive input from various areas of the brain and relay it back to the thalamus. It is a release circuit that works through disinhibition.

Question 16

The “gates” of the Basal ganglia are specific to what sensory modality?

Answer 16

Specific to motor control

Question 17

Lesions on the Basal ganglia often inhibits…

Answer 17

Habitual learning

Question 18

What is the Braking Function of the BG?

Answer 18

The BG intentionally inhibiting undesired movements.

Question 19

The cells in the striatum use __________, making them inhibitory/excitatory.

Answer 19

GABA, inhibitory

Question 20

What is a biasing switch?

Answer 20

A switch the biases information so that it flows through the correct pathway

Question 21

D1 cells form a _______ pathway.

Answer 21

direct

Question 22

D2 cells form a _______ pathway.

Answer 22

indirect

Question 23

One hypothesis of how the circuit engages is…

1. a signal is conveyed through the _________.
2. the ____________ selects movement.
3. at the same time, the ____________ inhibits the execution of other movements.

Answer 23

1. hyperindirect pathway
2. direct pathway
3. indirect pathway

Question 24

What type of cell is in this circuit? What part of the BG does it compose?

Answer 24

Medium Spiny Neurons make up the striatum

Question 25

Medium Spiny Neurons are divided into which 2 cell receptors? What are these receptors used for?

Answer 25

D1 and D2, used for the biasing circuit

Question 26

When DA binds to D1, _____________ occurs.

Answer 26

Depolarization

Question 27

When DA binds to D2, ____________ occurs.

Answer 27

Inhibition

Question 28

The Basal ganglia circuit can also be used for ___________ _________.

Answer 28

Reinforcement learning

Question 29

What are patches or striosomes?

Answer 29

Patches with a group of cells that receive and retain specific information

Question 30

Striosomes receive what kind of input?

Answer 30

Limbic

Question 31

Matrisomes receive what kind of information?

Answer 31

Cortical

Question 32

Striosomes: | Send ________ to _______.

Answer 32

sends ACh to SNpc.

Question 33

Matrisomes send _________ to ________ and ______.

Answer 33

sends GABA to GPi and SNpr.

Question 34

Cross-talk of the limbic and motor systems happens in the ...?

Answer 34

Basal ganglia

Question 35

Lesions on the BG circuit can lead to 2 kinds of disorders:

Answer 35

1. Hyperkinetic (Huntington's) | 2. Hypokinetic (Parkinsons)

Question 36

Name 2 hyperkinetic disorders. Which part of the BG needs to be damaged for these disorders to evolve?

Answer 36

Turrets, Huntington's. | Damage specifically to the striatum leads to these.

Question 37

Hypokinetic disorders are a result of...

Answer 37

Loss of biasing circuit

Question 38

What kind of disorder is a compulsive disorder?

Answer 38

Hyperkinetic

Question 39

Parkinson's disease is the loss of the _________ input, allowing for flow through the _________ pathway.

Answer 39

Dopamine, indirect pathway

Question 40

The flow of information through the indirect pathway causes __________.

Answer 40

Inhibition

Question 41

Parkinson's: How much DA (dopamine) does the cells need to lose before symptoms appear?

Answer 41

Over 90%

Question 42

What are some motor symptoms of Parkinson's?

Answer 42

Tremors, cogwheel rigidity, shuffling steps, etc.

Question 43

What are some non-motor symptoms of Parkinson's?

Answer 43

Cognitive slowing, difficulty with higher level processing, depression.

Question 44

Parkinson's: True or false: Giving patients Dopamine is an effective treatment for patients.

Answer 44

False, DA cannot cross the blood barrier

Question 45

Parkinson's: True or false: L-DOPA is an effective treatment for patients.

Answer 45

Yes and no. It is effective but not as a long-term treatment because the body adjusts to it.

Question 46

What is the most effective treatment for Parkinson's?

Answer 46

Fetal tissue transplant

Question 47

Parkinson's results from the deterioration of neurons in the ____________.

Answer 47

Substantia nigra.

Question 48

What is Deep Brain Stimulation?

Answer 48

DBS: a probe into the striatum, stimulate that cell so that things can go through the direct pathway, and the individual can move.

Question 49

Deep Brain Stimulation stimulates what part of the brain?

Answer 49

the striatum

Question 50

Huntington's disease is the loss of the ...?

Answer 50

Spiny Neurons

Question 51

What is the "Brake" hypothesis?

Answer 51

The BG is a gate that acts as a brake, preventing unwanted movement.