11. Motor Control and Disorders II Flashcards
Which Globus Pallidus region acts as the ‘brakes’ on motor action
Medial GP internal
the GP-internal is more active in which basal ganglia movement pathway?
the indirect pathway - suppresses movements
This basal ganglia pathway additionally goes through the lateral GP external and subthalamic nucleus
the indirect pathway
This basal ganglia movement pathway is excitatory
Direct pathway
the indirect and direct pathways occuring in parallel mean:
movements occur at the right order at right time
This movement disorder is idiosyncratic (affects everyone differently)
Parkinson’s disease
What is the Parkinson’s Mask? What are its consequences
loss of facial expression, can negatively affect communication
Which pathways are affected in Parkinson’s and how?
- Both
- reduced dopamine to putamen leads to underactive direct pathway and overactive indirect pathway
L-DOPA for parkinson’s can cause what after long periods of time?
dyskinesia - large exhaggerated movements (undesired)
How can deep brain stimulation to the STN aid parkinsons?
- more excitation to GPi, so more inhibition to thalamus and M1
- reduces the effect of the indirect pathway (increases activity of this pathway)
This motor disease is inherited via an autosomal dominant gene
Huntington’s Disease
Main symptom of Huntington’s?
Chorea - uncontrolled movement
What is the underlying pathology of Huntington’s?
- death of cells in the caudate and putamen (striatum) that input to the basal ganglia
- defect on gene coding for huntingtin protein
Which basal ganglia pathways are affected in huntington’s and how?
- indirect pathway
- underactive: less inhibition of unwanted movement
Which syndrome can lead to the presence of simple and complex tics, especially during stress?
Tourette syndrome
When might tics be less obvious in Tourette’s?
While the patient is concentrating
This basal ganglia condition is more common in boys
Tourette’s syndrome
True or false, tourette’s is hereditary
True
Which basal ganglia pathway(s) is affected in Tourette’s and how?
- direct pathway
- is overactive
What is the underlying pathology of Tourette’s syndrome (hint, opposite to Parkinson’s)?
- too much release of dopamine from substantia nigra
- genetic defect on molecule that is involved in dopamine biosynthesis
What is often used as treatment for Tourette syndrome?
- dopamine antagonists
Give examples of simple tics
eye blinking, nose twitching
Give example of complex tics:
scratching gestures, utterances, swearing
Which of the 3 movement disorders links to obsessive compulsive disorders
Tourettes
This movement disorder is developmental
Tourette’s
Huntington disease is associated with structural brain changes, these are:
Enlarged lateral ventricles due to less brain tissue/degeneration
