Basal Ganglia

Question 1

What comprises the striatum? lenticular nucleus? corpus striatum

Answer 1

• caudate nucleus + putamen
• putamen + globus pallidus
• putamen + caudate nucleus + globus pallidus

Question 2

Where is the caudate nucleus? function?

Answer 2

• floor of lateral ventricle

- eye movement + cognition

Question 3

Direct Pathway

Answer 3

cortex (Glu) + SNc (DA)—-> striatum (putamen) –GABA–> GPi +SNr –GABA–> Thalamus –Glu–> cortical motor areas

Question 4

Indirect Pathway

Answer 4

cortex (Glu) + SNc (DA) –> striatum (putamen) –GABA–> GPe –GABA–> STN –Glu–> GPi + SNr –GABA–> thalamus –Glu–>cortical areas

Question 5

What is the role of the following loops:

1. Skeletomotor loop
2. Oculomotor loop
3. Associative loop
4. Limbic loop

Answer 5

1. control of facial, limb, and trunk muscles
   - Putamen; GPi, SNr
2. control of saccadic eye movements
   - Caudate body; SNr, GPi
3. cognition and executive behavioral functions
   - Caudate; SNr, GPi
4. motivational regulation of behavior and in emotions
   - Ventral striatum; ventral pallidum, GPi, SNr

Question 6

What is the mxn of Parkinson’s Disease?

Answer 6

• SN does not release enough DA onto BG

Question 7

What are the symptoms of PD? what kind of disorder is it?

Answer 7

1. • rigidity
     - hypokinesia
     - akinesis
     - bradykinesis
     - resting tremor
     - visuoperceptive impairements
     - cogwheel rigidity
     - postural instability and dementia
2. Hypokinetic disorder

Question 8

Pt. presents with resting tremor, instability with walking, and slow beginning of movement. They have a history of Wilson’s Disease, and just finished a round of MPTP. What is the dx?

Answer 8

They have PD - Wilsons/MTPT are causes of it

other causes include: idiopathic PD, encephalitis lethargica, head trauma, CO + Mg poisoning, dopamine blocking drugs…

Question 9

What is the mxn of HD?

Answer 9

degeneration of neurons in the striatum and cerebral cortex, which results in GABA

Question 10

What are some causes of HD?

Answer 10

• sydenham chorea
• drug induced
• AD

Question 11

What is chorea?

Answer 11

spontaneous, rapid, jerky movements which are purposeless or fragments of motor programs

Question 12

What is athetosis?

Answer 12

inability to sustain the body part in one position (snake like movements)

Question 13

What is ballismus?

Answer 13

• faliling, flindign movement of thw wole extremity

- seen in lesions of contra subthalamic nucleus

Question 14

What is dystonia?

Answer 14

persistence or fixing of the posture at the extreme of an athetoid movement of either the extremities or trunk

Question 15

What causes hyperkinetic disorders?

Answer 15

• too little indirect pathway effect

- Chorea, athetosis, dystonia, ballismus