Exam Three - Basal Ganglia

Question 1

The ______ and ______ control postural reflexes and hand eye movements

Answer 1

brainstem and cerebellum

Question 2

the _____ and _____ control voluntary movement

Answer 2

cerebral cortex and basal ganglia

Question 3

3 levels of control of voluntary movement

Answer 3

1 - planning movement
2 - initiating movement
3 - executing movement

Question 4

what is involved in the planning movement phase

Answer 4

basal nuclei
cortical association areas
cerebellum

Question 5

what is involved in executing movement

Answer 5

cerebellum
movement

Question 6

the basal ganglia sends output to

Answer 6

cerebral cortex and brian stem

Question 7

T or F: all output from the cerebellum is inhibitory

Answer 7

T

Question 8

the basal ganglia is involved in (3)

Answer 8

1 - voluntary movement
2 - procedural learning associated with habits
3 - eye movements

Question 9

embryologically the basal ganglia arises from the ?

Answer 9

telencephalon

Question 10

what makes up the basal ganglia (4)

Answer 10

1 - striatum
2 - globus pallidus
3 - subthalamic nucleus
4 - substantia nigra

Question 11

caudate and putamen role

Answer 11

initiation and control of gross movement

Question 12

circuits of the basal ganglia

Answer 12

loops that involves the cortex, the basal ganglia, and thalamus

Question 13

the striatum normally works on this

Answer 13

GPi (inhibits it)

Question 14

this is involved in cognitive and proprioceptive control of movement

Answer 14

motor thalamus

Question 15

what is involved in the indirectly pathway

Answer 15

striatum
GPe
STN
GPi
Thalamus

Question 16

What does the GPe act on and what does it do

Answer 16

inhibits the STN

Question 17

what does the STN act on and what does it do

Answer 17

it excites the GPi

Question 18

what is the only excitatory pathway within the intrinsic basal ganglia

Answer 18

STN-GPi

Question 19

What happens in the indirect pathway

Answer 19

the striatum inhibits GPe which no longer inhibits STN. STN can now excite GPi which inhibits the thalamus so the thalamus is not sending motor info to the cortex. inhibition of unwanted movement

Question 20

focused selection

Answer 20

supression of competing motor programs

Question 21

the direct pathway is via

Answer 21

caudate/putamen

Question 22

what is affected in parkinsons

Answer 22

substantia nigra
locus coeruleus

Question 23

parkinsons is characterized by

Answer 23

abnormal movements
speed difficulties
cognitive changes

Question 24

hypokinetic disordered alter the balance of _______ signals in the direct and indirect pathways

Answer 24

inhibitory

Question 25

describe the direct pathway in parkinsons

Answer 25

substantia nigra -> D1 -> caudate/putamen -> globus pallidus internal -> VA/VL of thalamus - > frontal cortex

Question 26

describe the indirect pathway in parkinsons

Answer 26

substantia nigra -> D2 -> caudate -> globus pallidus external -> subthalamic nucleus -> globus pallidus interal -> VA/VL of thalamus -> frontal cortex

Question 27

in the direct pathway what is degenerated in parkinsons? indirect?

Answer 27

D1 D2

Question 28

If D1 and D2 are degenerated what happens?

Answer 28

D1 can't excite the direct pathway which leads to a diminished inhibition of the GPi segment so it inhibits the VA/VL more which leads to a decreased excitation of the frontal cortex D2 can't inhibit the indirect pathway so there is increased inhibition of the caudate/putamen on the GPe so it can't inhibit the subthalamic nucleus which has an increased excitation on the GPi so it inhibits the VA/VL more and leads to decreased excitation of the frontal cortex

Question 29

What are the 7 main symptoms of parkinsons

Answer 29

tremor slowed movement rigid muscle impaired posture and balance loss of automatic movements speed changes writing changes

Question 30

what is huntington's disease

Answer 30

progressive neurological disorder leading to neuron death and degeneration of the caudate and putamen

Question 31

huntington's disease direct pathway

Answer 31

the striatum dies so the GPi is less inhibited so it inhibits the thalamus more and there is decreased movement

Question 32

huntington's indirect pathway

Answer 32

the striatum dies so it can't inhibit GPe so it inhibits the STN more. The STN is turn can't excite GPi which will no longer inhibit the thalamus thus leading to increased movement

Question 33

chorea

Answer 33

sudden, rapid, jerky, purposeless movement involving limbs, trunk, or face

Question 34

dystonia

Answer 34

a condition of abnormal muscle tone that causes impairment of voluntary muscle movement

Question 35

what is the etiology of HD

Answer 35

an autosomal dominant mutation in the gene huntingtin CAG is repeated

Question 36

what is the most common cause of hemiballism. Where is the lesion?

Answer 36

stroke, subthalamic nucleus

Question 37

what causes chorea

Answer 37

pregnancy (gravidarum), huntingtons, infections, lupus, erythematosus, focal vascular lesions, PD, Levodopa

Question 38

what is degenerated in huntinton's (pathways?)

Answer 38

the connection between the caudate/putamen and globus pallidus

Question 39

what is involved in initiating movement

Answer 39

motor cortex

Question 40

the basal nuclei receives input from

Answer 40

cerebral cortex

Question 41

what is the associated ventricle of the basal ganglia

Answer 41

lateral ventricles

Question 42

putamen + caudate + nucleus accumbens =

Answer 42

striatum

Question 43

role of nucleus accumbens

Answer 43

encodes motor programs that facilitate the aquisition of a given reward in the future

Question 44

this connects to the glubus pallidus and receives afferents from substantia nigra and striatum. it also has a role in integration of somatic motor function

Answer 44

subthalamic nucleus

Question 45

what are the 2 main motor pathways of the basal ganglia

Answer 45

direct indirect

Question 46

this prevents unwanted muscles contractions from competing with voluntary movement

Answer 46

indirect pathway

Question 47

this facilitates the initiation and execution of voluntary movement

Answer 47

direct pathway

Question 48

the direct pathway starts with

Answer 48

the striatum

Question 49

the GPi normally does this

Answer 49

it inhibits the thalamus

Question 50

the thalamus normally does this to the cortex

Answer 50

excites

Question 51

in the direct pathway what happens?

Answer 51

the thalamus is disinhibited striatum inhibits GPi so GPi doesn't inhibit the thalamus anymore

Question 52

what does the striatum do to the GPe

Answer 52

it inhibits it

Question 53

direct pathway ________ the movement. Indirect pathway ________ the movement

Answer 53

starts, modulates

Question 54

the indirect pathway is via

Answer 54

subthalamic

Question 55

2 diseases associated with the basal ganglia

Answer 55

parkinsons huntingtons

Question 56

what causes parkinsons

Answer 56

loss of basal ganglia that release dopamine

Question 57

T or F: Parkinsons is a hypokinetic disorder

Answer 57

T

Question 58

In huntington's which pathway is affected first

Answer 58

indirect

Question 59

hemibalism

Answer 59

rare hyperkinetic movement disorder characterized by involuntary, violent, coarse and wide amplitude movements involving ipsilateral arm and leg

Question 60

T or F: Huntingtons is primarily a hyperkinetic disorder

Answer 60

T