Exam #6: Basal Ganglia Function Flashcards Preview

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Flashcards in Exam #6: Basal Ganglia Function Deck (31)
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1
Q

Define akinesia.

A

Lack of movement

2
Q

Define chroea.

A

Abnormal brief, random, twitch-like involuntary movement (dance-like)

3
Q

Define bradykinesia.

A

Slowness in the execution of movement

4
Q

Define atheotosis.

A

Slow, worm-like, writhing movements

5
Q

Define hemiballismus/ ballismus.

A

Involunatary, violent, flinging movements of a limb while awake
- Ballismus= bilateral

6
Q

Define dyskinesia.

A

General term for involuntary movements

7
Q

Define freezing of gait.

A

Seen in PD, patients will:

1) Suddenly be unable to start walking
2) Stop moving forward while walking

8
Q

Define festinating gait.

A

Abnormal gait seen in PD with small shuffling steps & absence of arm swing

9
Q

What are the structures that compose the basal ganglia?

A
  • Caudate
  • Putamen
  • Globus pallidus (internal & external segments)
  • Subthalamic nucleus
  • Substantia nigra (pars reticulata & pars compacta)
10
Q

Outline the nigrotriatial pathway. What NT is important in this pathway?

A

SNc to Striatum

  • DA
  • Has both excitatory and inhibitory effects
11
Q

Outline the corticostriate pathway. What NT is important in this pathway?

A

Cortex to striaum

  • Excitatory
  • Release glutamate
12
Q

Outline the pathway from the GPe to GPi. What NT is important in this pathway?

A

Striatum to GPe= GABA/ enkephalin (path. in Huntington’s)

Striatum to GPi= GABA

13
Q

Is GABA excitatory or inhibitory?

A

Inhibitory

14
Q

Is Glutamate excitatory or inhibitory?

A

Excitatory

15
Q

What are the symptoms of PD?

A
  • Resting tremor
  • Rigidity (“cogwheel”)
  • Slowness of movement
  • Postural instability
16
Q

Which transmitter system is most severely damaged in Parkinson’s Disease?

A

DA

17
Q

Damage to which part of the basal ganglia causes Parkinson’s disease?

A

SNc

18
Q

What are the symptoms to Huntington’s Disease?

A
  • Chorea
  • Dementia
  • Slow voluntary movements
19
Q

What is the location of the lesion that causes hemiballismus?

A

Lesion to the contralateral subthalamic nucleus

20
Q

What are the two functional loops of the basal ganglia?

A

Direct & indirect pathways

21
Q

What is the general function of the direct pathway?

A

Excitation

22
Q

What is the general function of the indirect pathway?

A

Inhibition

23
Q

Draw the direct pathway.

A

p. 105

24
Q

Draw the indirect pathway.

A

p. 105

25
Q

What is the corpus striatum?

A

Neostriatum + paleostriatum

= putamen + caudate nucleus + globus pallidus

26
Q

What is the neostriatum?

A

Striatum i.e. putamen + caudate nucleus

27
Q

What is the paleostriatum?

A

Pallidum i.e. globus pallidus

28
Q

Where do the main afferents to the basal ganglia synpase?

A

Striatum i.e. putamen + caudate nucleus

29
Q

Where do the main efferent from the basal ganglia emerge?

A

Globus pallidus

30
Q

What is the general circuit of the basal ganglia?

A

1) Cortex
2) Stratium
3) Pallidum
4) Thalamus

31
Q

What are the four functional loops of the basal ganglia?

A

1) Body movement loop
- Motor cortex
- Internally generated movements

2) Oculomotor loop
- Frontal eye fields
- Saccadic eye movements

3) Prefrontal loop
- Dorsal PFc
- Initiation & termination of cognitive processes

4) Limbic loop
- Addiction to drugs of abuse
- Behavior & motivation

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