Week 6

Question 1

What is the basil ganglia?

Answer 1

Collection of 5 related grey matter structures located deep within the brain

Question 2

What are the 5 structures of the basil ganglia?

Answer 2

1. Striatum - Caudate nucleus + putamen
2. Globus pallidus externus
3. Globus pallidus internus
4. Sub thalamic nucleus
5. Substantia nigra

Question 3

What is the function of the basil ganglia?

Answer 3

Movement commands from the motor cortex are sent to the Basal Ganglia nuclei for checking. Once processed there they are sent back to the Motor Cortex (via the Thalamus) to be executed. It regulates desired and inhibits undesired movements

Question 4

What are the 3 pathways within the basil ganglia?

Answer 4

• Direct pathway
• Indirect pathway
• Hyper direct pathway

Question 5

What is the role of the direct pathway?

Answer 5

Allows movement to take place, by taking away the inhibition of the thalamus to allow it to be more active, as the thalamus talks to the motor cortex which talks to our muscles

Question 6

What is the role of the indirect pathway?

Answer 6

Stop pathway that helps us avoid unwanted movement, by exciting the golbus pallidus which results in it tightening its leash on the thalamus, and preventing unwanted movement

Question 7

Why do we need balance between the direct and indirect pathways?

Answer 7

So refined, appropriate and wanted movement can be produced

Question 8

What is the role of the substantia nigra?

Answer 8

Releases dopamine which binds by dopamine receptors in the striatum

Question 9

What is glutamate?

Answer 9

An excitatory neurotransmitter

Question 10

What pathway does Huntingtons disease effect?

Answer 10

Indirect pathway

Question 11

What pathway does Parkinsons disease effect?

Answer 11

Both pathways

Question 12

What is the role of the striatum (caudate + putamen)?

Answer 12

Receives input from the cortex

Question 13

What is the role of the globus pallidus internus?

Answer 13

Sends inhibitory signals to motor thalamus

Question 14

What is the role of the globus pallidus externus?

Answer 14

Modulates indirect pathway. Regulates activity of subthalamic nucleus

Question 15

What is the role of the subthalamic nucleus?

Answer 15

Provides excitatory input to GPi in the indirect pathway

Question 16

What are the 3 functional areas of the cerebellum?

Answer 16

1. Spino cerebellum (vermis)
2. Vestibulo-cerebellum
3. Cerebro-cerebellum

Question 17

Spino cerebellum (vermis) functions

Answer 17

Makes anticipatory, corrective and responsive adjustments or otherwise movement would be uncoordinated

Question 18

Vestibulo-cerebellum functions

Answer 18

Role in head movement and head position

Question 19

Cerebrocerebellum functions

Answer 19

Role in timing movements, planning movements and coordination of voluntary movement

Question 20

What is the function of the cerebellum?

Answer 20

The cerebellum receives info from the spinal cord and the brainstem, then feeds that information through the thalamus and cerebral cortex to influence that movement

Coordinates human movement (including direction, timing/speed and force), role in adjusting posture

Question 21

Signs of vestibulocerebellum dyfunction?

Answer 21

• Unsteadiness
• Truncal ataxia
• Nystagmus - (Abnormal eye movements)

Question 22

Signs of spinocerebellum dyfunction?

Answer 22

• Intention tremor (occurs during purposeful movements)
• Ataxic gait
• Dysmetria
• Dysarthria (speech difficulties)

Question 23

Signs of cerebrocerebellum dyfunction?

Answer 23

• Finger ataxia (loss of control)
• Dysarthria (slurred speech)

Question 24

What is Parkinson’s disease?

Answer 24

Progressive, neurodegenerative movement disorder that effects the brain due to degeneration of the basil ganglia

Question 25

What is the phase in Parkinson's disease where symptom onset occurs before the person is diagnosed?

Answer 25

Prodromal phase

Question 26

What are some common PD impairments?

Answer 26

Bradykinesia - slowness of movement Resting tremor - involuntary movement at rest Hypokinesia - reduced frequency of movement Postural inability - awkward and reduced postural adjustments Akinesia - absense of movement or difficulty starting movement Loss of facial expression Mumbled speech Reduced voice volume

Question 27

What is the differnece between on and off time with PD medication?

Answer 27

On time – Parkinson’s medication is effective – less impairments Off time – medication has worn off – most impairments Wearing off – medication wearing off – increasing impairments

Question 28

What is Huntington's disease?

Answer 28

A hereditary, degenerative disorder of the basil ganglia that causes nerve cells in the brain to break down - Long pro-dromal period

Question 29

What are some common HD impairments?

Answer 29

- Movement disorders - Cognitive disorders - Emotional and behavioural disorders - Communication disorders - Sleep disorders

Question 30

PD medications

Answer 30

Kinson: -Levodopa is a chemical closely related to dopamine which allows the body to make its own dopamine. – gets converted into dopamine in the brain -Carbidopa makes sure that enough levodopa gets to the brain where it is needed. Madopar: - Levodopa on its own (which is a precursor of dompamine) Rotigotine: - Dopamine agonist