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Flashcards in Basal Ganglia Deck (36):
1

What was classically included in the basal ganglia

caudate nucleus & lentiform nucleus

2

What is another name for globus pallidus

paleostriatum (pallidum)

3

What is another name for caudate + putamen

neostriatum (striatum)

4

What is included in the paleostriatum/pallidum

globus pallidus interna
globus pallidus externa

5

What is included in the neostriatum/striatum

caudate
putamen

6

What is currently included in the basal ganglia

paleostriatum (pallidum) - GPin, GPex
neostriatum (striatus) - putamen & caudate
substantia nigra
subthalamic nucleus

7

What is the function of the basal ganglia?

influences UMNs for the initiation and control of MSK motor activity

8

Where does the tail of the caudate nucleus end?

tail extends down into temporal lobe and ends adjacent to the amygdala nucleus (limbic system)

9

What are the two subnuclei of the lentiform nucleus?

putamen
globus pallidus (GPin, GPex)

10

Where are the caudate and putamen continuous with each other?

around the anterior limb of the internal capsule

11

What is the corpus striatum? What does it include?

region occupied by the basal ganglia at the base of the forebrain
includes neostriatum and paleostriatum

12

What is the subthalamus?

diencephalic motor nucleus

13

What is the substantia nigra?

Mesencephalic motor nucleus

14

DRAW THE MOTOR PATHWAYS INVOLVING THE BASAL GANGLIA.

See notes

15

The connection between the basal ganglia and the thalamus is all from the

globus pallidus interna

16

What is the overall effect of the direct pathway?

Increases motor output

17

What is the overall effect of the indirect pathway?

Decreases motor output

18

What effect does dopamine have on the basal ganglia?

excites direct pathway and inhibits indirect pathway
results in increase of motor output

19

What dopamine receptors are associated with the direct pathway? Are they excitatory or inhibitory?

D1
excitatory

20

What dopamine receptors are associated with the indirect pathway? Are they excitatory or inhibitory?

D2
inhibitory

21

What is the fundamental pathology behind Parkinson's Disease?

dopaminergic neurons in pars compacta diminish over time

22

What are characteristics of PD?

bradykinesia
rigidity
inc reflexes
mask-like face
festinating gait
resting tremor (pill-rolling)

23

True or False: dopamine crosses the BBB

False

24

What is given as a treatment for PD? Why?

L-dopa crosses BBB
can increase efficiency of the undegenerated neurons in the SN

25

Is Huntington's disease hypokinetic or hyperkinetic?

hyperkinetic

26

Is PD hypokinetic or hyperkinetic?

hypokinetic

27

What degenerates in HD?

degeneration of neurons seen in neostriatum initially and in deeper layers of frontal cortex

28

How does HD present in the early stages?

irritability, forgetfulness, clumsiness

29

How does HD present in late stages.?

choreiform movements
dementia
fatal

30

Is there a treatment for HD?

No

31

What is the mechanism of neuronal degeneration in HD?

glutamate persistence at NMDA receptor sites in affected neurons opens the neurons to Ca which increases neuron excitability
neurons degenerate (excitotoxicity)

32

What causes hemiballismus?

Penetrating vessel arising from medial component of posterior cerebrals goes to subthalamus. Hemiballismus results from infarcts in subthalamus. Takes the subthalamus out of the indirect pathway so there is uncontrolled cortical output.

33

What is the symptom of hemiballismus?

contralateral violent contraction of proximal musculature (ballistic movements)

34

Is hemiballismus reversible?

As long as the vascular lesion resorbs the condition will diminish.

35

What is an "extrapyramidal" syndrome?

dyskinesia that results from an insult to the basal ganglia

36

The pars reticulata is functionally analagous to the

globus pallidus interna