Task 2

Question 1

What do we call the kind of inhibition the Basal Ganglia has on the Cortex?

Answer 1

Tonic Inhibition

Question 2

Activation of the Striatum leads to:

• activation of the cortex
• inhibition of the cortex
• disinhibition of the cortex

Answer 2

Inhibition of the cortex

Question 3

The Caudate and the Putamen together form the:

Answer 3

Striatum

Question 4

Describe the direct output pathway of the Basal Ganglia.

Answer 4

Striatum -> Substantia Nigra (r)/GPi -> Thalamus -> Cortex

Question 5

Describe the indirect pathway of the basal ganglia.

Answer 5

Striatum -> Globus Pallidus externus -> Subthalamic Nucleus -> GPi/Substantia Nigra (r) -> Thalamus -> Cortex

Question 6

Choose inhibits or excites:
The Globus Pallidus constantly ___ the thalamus. The Subthalamic Nucleus ____ the Globus Pallidus, thus preventing unwanted movements from happening. The Direct Pathway ____ the Substantia Nigra directly.

Answer 6

Inhibits, Excites, Inhibits

Question 7

There are two types of dopamine receptors in the Basal Ganglia. Which type is present in which pathway?

Answer 7

D1 -> Direct Pathway

D2 -> Indirect Pathway

Question 8

Which of the two dopamine receptors of the Basal Ganglia is inhibitory?

Answer 8

D2

Question 9

What are two well-known diseases of the Basal Ganglia?

Answer 9

Huntington’s and Parkinson’s

Question 10

Huntingtons is part of the class of ___ disorders.

Answer 10

Neurodegenerative

Question 11

Huntingtons results in hyperkinesia and chorea. What does this mean?

Answer 11

Hyperkinesia = Excessive Movements
Chorea = Involuntary Movements

Question 12

What is the biological basis of Huntingtons?

Answer 12

Atrophy in the Striatum, which leads to disinhibition of the thalamus and thus the cortex.

Question 13

Next to anomalies in posture, Parkinsons also leads to Hypokinesia and Bradykinesia. What does this mean?

Answer 13

Hypokinesia = Reduced voluntary movements 
Bradykinesia = Slowness of movements

Question 14

What happens biologically in the brain of a Parkinsons patient?

Answer 14

Atrophy of dopaminergic neurons in the SNc

Question 15

Why do reflexes and spasticity gain control after damage to upper motor neurons?

Answer 15

Spasticity is an over-contraction of muscles in reflexes counteracting gravity, which are no longer controlled by the cortical signals.

Question 16

What is a limitation of using Deep Brain Stimulation as a treatment for Parkinson or Huntingtons?

Answer 16

For one location and one intensity/frequency setting, the stimulator in the brain has different effects on the different loops in the brain, leading to unwanted effects.

Question 17

On what kind of genetic abnormality is Huntington based?

Answer 17

A repetition of a CAG sequence

Question 18

What are three non-motor loops that the Basal Ganglia are involved in?

Answer 18

Parallel Loops
Dorsolateral Prefrontal Loop
Limbic Loop

Question 19

What is the function of the Dorsolateral Prefrontal Loop and the brain parts involved in it?

Answer 19

• Involved in initiation of cognitive processes

- Dorsolateral PFC -> Anterior Caudate -> GPi -> Mediodorsal and ventral anterior thalamic nuclei -> Cortex

Question 20

The Cortical loops of the basal ganglia all go though different parts of which subcortical structures?

Answer 20

Striatum, Globus Pallidus, Thalamus

Question 21

What sequence does the limbic loop go through?

Answer 21

Limbic Lobe -> Ventral Striatum -> Ventral Pallidum -> Mediodorsal Thalamic Nucleus