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Flashcards in Basal Glanglia Deck (31)
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1
Q

Basal ganglia structures

A
Caudate 
Putamen
Globus pallidus 
Subthalamic nucleus
Substantia nigra
2
Q

Striatum

A

Caudate and putamen

3
Q

Lenticular nucleus

A

Putamen

Globus pallidus

4
Q

Basal ganglia function

A

Indirect influence on movement via the thalamus

PIE - planning, initiation, execution of movement

5
Q

Other basal ganglia functions

A

Postural control
Maintaining muscle tone
Production of automatic movements

6
Q

Does the basal ganglia receive sensory input?

A

No

7
Q

Basal ganglia - input nuclei

A

From cortex

Primarily striatum(caudate, putamen)

Also substantia nigra

8
Q

Basal ganglia - output nuclei

A

To thalamus

Via the globus pallidus inter us and substantia nigra

9
Q

Two pathways exist from input to output basal ganglia nuclei

A

Direct pathway and

Indirect pathway

10
Q

Direct pathway

A

net effect: thalamus excitation

Disinhibition

facilitating movement
Increased movement

11
Q

Indirect pathway

A

net effect: thalamus inhibition

inhibiting movement
Decreased movement

12
Q

BG inhibits the thalamus

A

Input to thalamus is inhibitory via globus pallidus and substantia nigra

13
Q

Normal BG output at rest

A

Some amount of inhibition on the thalamus

How much of thalamus is inhibited by GB determines if movement will occur or not

14
Q

BG and cortex

A

Cortex contributes to how much the BG inhibits thalamus via the direct and indirect pathways

15
Q

Thalamus not/less inhibited

A

Disinhibited = INCREASED movement

16
Q

Thalamus inhibited

A

Decreased movement

17
Q

BG has other than news for different functions

A

Passes through different pathways and projects to frontal lobe and limbic system

Motor (movement), oculomotor (eye movement), prefrontal (cognitive processes), limbic (emotion and motivational drives- neurobehavioral and psych disorders)

18
Q

Common movement disorders no/slow movement —> fast

A
Akinesia
Bradykinesia/hypokinesia
Rigidity 
Dystopia
Athetosis
Chorea
Ball is us
Tics
Myoclonus
Tremor
19
Q

BG and dyskinesia

A

Abnormal movement caused by BG dysfunction

Akinesia
Bradykinesia
Rigidity

20
Q

Rigidity

A

Increased, uniform resistance to passive movement of a limb throughout the entire ROM

Superimposed by rachetlike jerkiness to passive movement of a limb

21
Q

Movement disorders - involuntary movements

A
Dystonia (sustained contractions)
Athetosis (writhing)
Chorea (rapid, irregular,jerky)
Ballismus (large amp, sudden flailing)
Tics (twitches)
Myoclonus (cyclical, spasmodic alteration in contract and relax)
22
Q

Tremor

A

Rhythmic or semi-rhythmic oscillation movement

23
Q

Resting tremor

A

Often seen w/ BG lesion

Obvious when limbs are at rest, decreases/stop when pt moves limbs

24
Q

Parkinon’s disease

A

Idiopathic neurodegenerative condition caused by loss of dopaminergic neurons in substantia nigra

25
Q

Parkinson’s triad

A

Bradykinesia, rigidity, resting tremor —>

Postural instability, unsteady gait

26
Q

Parkinson’s onset, progression

A

45-65 yo
M>F
Progression is gradual leading to severe disability

Reasons well to LevoDopa

27
Q

Which pathway more effected w/ Parkinson’s?

A

Direct pathway

DA normally has excitatory effect on direct ath way and inhibitory effect on indirect

W/ loss of DA—> underactive direct pathway, overactive indirect pathway —> no/less movement

28
Q

Huntington’s disease

A

Autosomal dominant neurodegenerative disease

Progressive - usually choreiform movement disorder, along w/ dementia and psych disturbances, ultimately lead to death

Progressive atrophy of caudate nucleus and also putamen

29
Q

Huntington’s onset

A

30-50 yo

Initial symptoms: subtle chorea, behavioral disturbances

Death usually occurs w/in 10-15 yr after onset

30
Q

Huntington’s characterized by

A

Abnormalities of body movements, emotions, cognition

Tics, athetosis, dystopia posturing

31
Q

Which pathway more effected - Huntington’s?

A

Indirect!

Less/no Enk released by striatum

Result is disinhibition of thalamus which produces movement