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Flashcards in lecture 7 basal ganglia Deck (39)
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1

what are the five major nuclei of the basal ganglia?

-caudate nucleus
-putamen
-globus pallidus- internus and externus
-subthalamic nuclei
-substantia nigra

2

what two nuclei make up the striatum?

caudate nucleus and putamen

3

what two nuclei make up the lenticular nucleus?

putamen and globus pallidus

4

where does the caudate nucleus run?

runs with the lateral ventricle

5

where is the lenticular nucleus?

deep to the insula
-putamen- most lateral, joined to caudate head at the ventral striatum (includes nucleus accumbens)
-globus pallidus- pointed medially

6

where is the substantial nigra located?

2 parts in the rostral midbrain, between the cerebral peduncles and the red nuclei
-compacta
-reticularis

7

where is the sub thalamic nuclei located?

inferior to the thalamus

8

what the functions of the basal ganglia nuclei?

-muscle contraction regulation: force, multi joint coordination, sequencing, imitation of learned sequences of movement
-input from cortex

9

true or false the direct circuit is inhibitory to the cortex

false the direct circuit excites the cortex

10

true or false the indirect circuit inhibits the cortex

true

11

what are the 3 primary inputs in the circuitry?

-premotor and sensorimotor cortex to putamen to globus pallidus internus to ventrolateral thalamus
-cortex to caudate to globus pallidus internus to ventrolateral thalamus
-subthalamic nuclei to globus pallidus to ventrolateral thalamus

12

what are the 2 primary outputs to the circuitry?

-globus pallidus- GABA inhibitory n. via ansa lenticularis and lenticular fascicles bundles to thalamus
-substantia nigra reticularis- GABA inhibitory to thalamus

13

what 5 types of neurotransmitters can be found in the basal ganglia?

-glutamate
-GABA
-Substance P
-Enkephalins
-Dopamine

14

what are the two types if dopamine receptors and where do the originate?

originate in the substantia nigra
-D-1: excites the direct path
-D-2: inhibits the indirect path

15

True or false: both D-1 and D-2 impact the different paths by increases excitation to the cortex

TRUE

16

where is the nucleus accumbens?

where the head of the caudate and anterior putamen meet

17

what is the nucleus accumebens?

collection of GABA inhibitory cell that connect with
-globus pallidus>dorslamqdial thalamus> prefrontal cortex
-substanita nigra and pontine reticular formation

18

where does the nucleus accumbens get input from?

amygdala and ventral tegmentum

19

what are the roles of the nucleus accumbens?

-drug addiction via increased dopamine in cells
-musical effects on emotion
-rhythmic timing
-depression

20

What are positive signs and list 7 examples

positive signs are involuntary muscle contractions; something you can see
Examples:
-resting tremor
-rigidity
-chorea
-dyskinesia
-dystonia
-athetosis
-ballism

21

what are negative signs and list 2 examples

negative signs are lack of muscles contractions; things you can't see
Examples:
-bradykinesia
-hypokinesia/ akinesia

22

what is a resting tremor?

positive sign: rhythmic oscillations

23

what is rigidity?

positive sign: increased resistance to movement in all muscles, hypertonicity

24

what is chorea?

positive sign: continuous rapid movements (degradation of the caudate nucleus seen in Huntington's)

25

what is dyskinesia?

positive sign: involuntary movement during a voluntary action

26

what is dystonia?

positive sign: involuntary sustained muscle contraction

27

what is athetosis?

positive sign: writhing movements (stratal lesions)

28

what is ballism?

positive sign: fast movement of whole limbs (lesions of contralateral sub thalamic nuclei)

29

what is bradykinesia?

negative sign: slow movements

30

what is hypokinesia or akinesia?

negative sign: few or no movement (reduced dopamine from substantia nigra to stratum- parkinson's)
-lead pipe rigidity
-cog- wheel rigidity

31

what two structure degenerate in Parkinson's?

substantial nigra and pedunculo pontine nuclei

32

what are the 2 signs or Parkinson's?

-hypokinetic- movement freezing, postural instability, reduced imitation of movement
-hyperkinetic- rigidity, resting tremors

33

what are the 3 treatments for Parkinson's?

-L dopa
-Deep brain stimulation, ablation, or neuronal transplants/ stem cells
-Optokinetic triggering for smoother movement patterns

34

what are the 2 causes of Huntington's?

-hereditary
-degernation of striatum and cortex

35

what are the signs of Huntington's?

-hyperkinetic- continuous movement in dancelike or writhing patterns
-hallucinations
-outbursts
-depression

36

what are the 2 treatments for Huntington's?

-management of psychological changes
-medications to slow progression rate, control motor symptoms, block excitotoxins that disrupt energy metabolism of cells

37

what are the 2 pathologies for dystonias?

-genetic: focal, involuntary sustained contractions
-acquired: overuse

38

what are the symptoms of dystonias?

-cramping
-movement decomposition, decreased isolation of digits

39

what are the two treatments for dystonias?

-pharmacological: botox
-acquired: responsive retraining