Parkinson's disease

Question 1

what are the motor symptoms of parkinsons

Answer 1

tremor
akinesia
bradykinesia
hypographia
festinating gait
stooped or hunched posture
masked face
soft/low voice
unstable balance

Question 2

what is the most common symptom of parkinsons

Answer 2

tremor
- uncontrolled shaking that often first presents in the hands

Question 3

what is akinesia

Answer 3

muscle rigidity - often begins in the legs and neck

Question 4

what is bradykinesia

Answer 4

slowness of mvmt
- become increasingly slow with the disorder progression

Question 5

what is festinating gait

Answer 5

slowness of gait, small shuffled gait, wide base of support

Question 6

why do they have unstable balance

Answer 6

prone to falling due to reduced reflex activity

Question 7

does parkinsons cause hypermetric or hypometric reflexes

Answer 7

hypometric

Question 8

why does parkinsons cause hypometric reflexes

Answer 8

impairs balance control by disrupting the amplitude and scaling of relfex responses in the agonist/antagonist muscles
- because basal ganglia is key for balance control
- reduction in agonist muscles in parkinsons

Question 9

how does the stooped posture reduce stability of standing balance

Answer 9

stooped posture changes the mechanics of balance
stability boundary is reduced in parkinsons

Question 10

what causes parkinsons

Answer 10

dopamine deficiency in the SNc

Question 11

does parkinsons cause hypokinetic or hyperkinetic symptoms

Answer 11

hypokinetic symptoms

Question 12

how does the dopamine deficiency lead to hypokinetic symptoms

Answer 12

• excitatory connections from SNc to the putamen are ineffective
• putamen doesn’t inhibit the GPi
• GPi activity is high, releases inhibitory NT and reducing the activity of the thalamus
• blocks excitation of cortical motor areas
• leads to reduction in the activity required to produce mvmt

Question 13

what occurs to dopamine producing neurons in SNc during parkinsons

Answer 13

depleted and die off
- progressive neurodegeneration

Question 14

what is shown on a PET scan with parkinsons

Answer 14

shows depletion of dopaminergic neurons in SNc
- leads to reduction of dopamine metabolism in the striatum

Question 15

what is the prevalence of parkinsons

Answer 15

second most prevalent neurodegenerative disease
- 1 in 500 people in canada
- more prevalent in males than females

Question 16

what are the two main treatments for parkinsons

Answer 16

L dopa (Levodopa)
deep brain stimulation (DBS)

Question 17

is the indirect or direct basal ganglia pathway inhibited during parkinsons

Answer 17

direct pathway inhibited

Question 18

what is L dopa

Answer 18

amino acid produced by typical bio function
dopamine precursor
used to treat symptoms
- doesn’t alter / prevent progression

Question 19

what is deep brain stimulation

Answer 19

electrode implanted in brain that can replace the excitatory input from the substantia nigra