Parkinson's disease

Question 1

What is ataxia, what are examples of what it can impair, and damage to what part of the brain can causes it?

Answer 1

A lack of voluntary coordination of muscle movements

Can impair speech, walking and eye movements

Damage to the cerebellum

Question 2

What is apraxia, and what can it cause difficulty with?

Answer 2

An impaired ability to plan motor movements (muscles aren’t impaired).

It can cause difficulty with walking and talking

Question 3

What can hyperkinetic movements be grouped into, and give examples of each?

Answer 3

Jerky movements (e.g. tics and chorea)

Non-Jerky movements (e.g. dystonia and tremors)

Question 4

What is ballismus, what is the physiological cause, and what neuropathology can cause it?

Answer 4

Spontaneous, involuntary movements (flailing) one one side of the body

Caused be decreased activity in the sub thalamic nuclei (which excites the inhibition of the thalamus in the indirect pathway)

Can be caused by stroke

Question 5

What is a tic, and what can increase/decrease it?

Answer 5

Repetitive, sudden and uncontrollable motor movements/vocalisations

Anxiety increases it

Distraction and concentration can decrease it

Question 6

What is Tourrette’s syndrome?

Answer 6

A spectrum of tic disorders with multiple motor tics and at least one vocal tic

Question 7

What co-morbidities are commonly associated with tic?

Answer 7

ADHD
OCD
Anxiety

Question 8

What is chorea and its cause?

Answer 8

Brief, irregular and jerky contractions that aren’t rhythmic or repetitive and it can flow from one muscle to the next.

Caused by a decrease in activity of the sub thalamic nuclei

Question 9

How many CAG repeats indicate Huntington’s Disease

Answer 9

36 or more

Question 10

What are the different types of clinical presentations of Huntington’s Disease, and give some examples?

Answer 10

Cognitive (Slow thoughts, difficulty multitasking)

Behavioural (irritability, depression, anxiety, delusions)

Physical (Dystonia, chorea)

Question 11

What is myoclonus, and what is it thought to be caused by?

Answer 11

Brief movements with a rapid onset and offset. They can be muscular contractions (+ve) and inhibitions (-ve)

Imbalance of excitatory and inhibitory neurotransmitters

Question 12

What is dystonia and what is the cause thought to be?

Answer 12

Abnormal twisting posture that can be associated with a jerky tremor.

Abnormal dopaminergic activity in the basal ganglia

Question 13

What are some clinical causes of dystonia?

Answer 13

Stroke

Brain injury

Parkinson’s/Huntington’s Disease

Question 14

What is a tremor?

Answer 14

Involuntary, rhythmic movements of parts of the body

Question 15

What drugs can treat hyperkinetic movements?

Answer 15

D2 receptor blockers (e.g. haloperidol, risperidone and chlorpromazine)

Dopamine depleting agents (tetrabenazine)

Atypical antipsychotics (e.g. clozapine)

Question 16

What can antipsychotic drugs, and other D2 receptor blockers, induce?

Answer 16

Drug-induced Parkinsonian symptoms:

• Slow movements
• Stiffness
• Shaking

Question 17

Reduced input of what neurotransmitter, in what part of the brain, leads to Parkinson’s?

Answer 17

Dopamine

Substantia nigra

Question 18

The impaired dopaminergic activity in the substantia nigra of a sufferer of Parkinson’s would disrupt the ratio of dopamine with what other neurotransmitter?

Answer 18

ACh

Question 19

What are monoamine oxidase inhibitors and what are the two types?

Answer 19

Prevent the breakdown of monoamine neurotransmitters

Type A: Works for serotonin, nor/adrenaline and dopamine
Type B: Only works for dopamine

Question 20

What is Selegilline and what can it be used to treat?

Answer 20

Type B MAOi used to treat Parkinson’s disease

Question 21

What is the gold standard drug to treat Parkinson’s

Answer 21

Levodopa, which can get converted into dopamine

Question 22

What must Levodopa always be given with, and why is this the case?

Answer 22

Dopa decarboxylase inhibitor so that peripheral conversion into dopamine won’t occur

Question 23

What is apomorphine?

Answer 23

Dopamine agonist that can instantly reduce dyskinesia by allowing continuous dopaminergic stimulation