Motor 2

Question 1

is overall movement controlled by one neuron ?

Answer 1

no

- integrated activity of many neurones

Question 2

when there is a body position change, is there feedback messages from brain stem vestibular nuclei to the spinal cord neurones?

Answer 2

yes

Question 3

what is feed forward mechanisms control of movement?

Answer 3

before a movement occurs, brain stem reticular formation nuclei make adjustments to stabilise posture

Question 4

what is feed back mechanism control of movement?

Answer 4

after a movement occurs, information from the brain stem vestibular nuclei travels to the spinal cord to correct posture and balance

Question 5

what is babinskis sign?

Answer 5

plantar extension

Question 6

does babinskis signs show upper or lower motor neuron disease?

Answer 6

upper motor neuron disease

Question 7

what is hypotonia?

Answer 7

loss of tone in muscles

- flaccid

Question 8

what is the major sub cortical input to SMA of area 6?

Answer 8

ventral lateral nucleus in dorsal thalamus

Question 9

where does the ventral lateral nucleus come from?

Answer 9

basal ganglion

Question 10

state the 4 steps of the information loop which initiates voluntary movements

Answer 10

cortex -> basal ganglion -> VLo -> SMA of area 6

Question 11

state the two input zones of the basal ganglia?

Answer 11

caudate

putamen

Question 12

does corpus striatum receive input from all over the cortex?

Answer 12

yes

Question 13

what parts of the basal ganglia receive excitatory (glutamatergic) cortical inputs?

Answer 13

putamen

caudate

Question 14

what parts of the basal ganglia receive inhibitory (GABAergic) cortical inputs?

Answer 14

globus pallidus

substantia nigra

Question 15

which two parts of the basal ganglia fire APs before the movement?

Answer 15

putamen

caudate

Question 16

which two parts of the basal ganglia are predictive of movements?

Answer 16

putamen

caudate

Question 17

what is the functional consequence of cortical activation of putamen ?

Answer 17

excitation

Question 18

at rest are the globus pallidus neurones active or inactive ?

Answer 18

active

Question 19

what is the direct pathway of cortical input through the basal ganglia?

Answer 19

cortex -> puatmen + caudate -> globus pallidus -> thalamus

then back to the cortex to the SMA

Question 20

what is the indirect pathway of cortical input through the basal ganglia?

Answer 20

1. cortex stimulate the sub thalamus nuclei
2. excites the globus pallidus
3. inhibits the thalamus
4. cells are released from VLo (part of thalamus)
5. this excites the SMA

Question 21

what is the function of the direct pathway of cortical input?

Answer 21

selects specific motor actions

Question 22

what is the function of the indirect pathway of cortical input?

Answer 22

suppresses competing/inappropriate action

Question 23

whats the main cause of Parkinsons disease?

Answer 23

degeneration of neurones in substrantia nigra (SN) and their dopaminergic (excitatory) inputs to the striatum

Question 24

what is the clinical complication of not being able to produce dopamine by the substantia nigra in parkinsons disease?

Answer 24

depletion of dopamine closes down activation of the focussed motor activities that funnel through thalamus to SMA
- difficulty making voluntary movements

Question 25

what causes Huntington disease?

Answer 25

profound loss of caudate, putamen and globus pallidus

- so loss of the ongoing inhibitory effects of the basal ganglia

Question 26

what is chorea ?

Answer 26

spontaneous, uncontrolled, rapid flicks and major movements with no purpose

Question 27

what is the main function of the cerebellum?

Answer 27

regulate movement

- instructs direction, timing and force

Question 28

what happens when there is a lesion on the cerebellum ?

Answer 28

uncoordinated inaccurate movements

Question 29

via what structure does the cerebellum send information back to the cortex?

Answer 29

ventrolateral thalamus

Question 30

state the four stages of the feedback loop involving the cerebellum?

Answer 30

pons, cerebellum, thalamus and back to cortex