Week 9B

Question 1

What nucleus within the basal ganglia contains dopaminergic
neurons? Where does this nucleus project to within the basal ganglia

Answer 1

Substantia nigra

projects to the striatum - dopamine transmission

projects to subthalmic nucleus - inhibitory neurotranmitter - back in neg feedback loop

Question 2

Some antipsychotic medication used to treat schizophrenia works to inhibit dopamine transmission and can cause Parkinsonian-like
symptoms.
B) Explain how this type of antipsychotic medication may cause Parkinsonian-like symptoms within the context of the Basal Ganglia’s
direct pathway (diagram may be useful).

Answer 2

when dopamine transmission is inhibited striatum not excited and it can no longer inhibit GPI as much

GPI inhibits the thalamus more

thalamus decrease excitation onto motor cortex

decrease cortex activation of muscles = PD sumptoms

Question 3

explain the path of parkinsons from the decrase in dopaine to PD symptoms - use diagram

Answer 3

when dopamine transmission is inhibited striatum not excited and it can no longer inhibit GPI as much

GPI inhibits the thalamus more

thalamus decrease excitation onto motor cortex

decrease cortex activation of muscles = PD sumptoms

Question 4

where are 50% of our brains neurons located?

Answer 4

cerebellum

Question 5

the cerebellum is referred to as out ____ because it ___

Answer 5

comparator compares intention vs what actually happeneed

Question 6

does cerebullm receive afferent or efferent motor info

Answer 6

both!

Question 7

what are three functions of the cerebellum?

Answer 7

balance and posture maintenance
coordination of voluntary movements
motor learning

Question 8

The cerebellum coordinates the ___ and ___ of msucles to ensure ___ movments

Answer 8

timing and force ensure smooth movement - control voluntary movements

Question 9

cerebellum is improtant for maintenance of ___ and ___

Answer 9

balance and posture

Question 10

similar to cerebrum the cerebellumhas 2 ____ hemispheres

Answer 10

symmetric

Question 11

what are the 4 symmetrical sections of the cerebellum?

Answer 11

1. hemispher
2. vermis
3. intermediate zone
4. floculondular lobe

Question 12

what are the 3 pathways in the cerebellum?

Answer 12

spinocerebellar
cerebrocerebellar
vestibulocerebellar

Question 13

where is the spinocerebellar path located ?

Answer 13

vermis and intermediate zones

Question 14

what is the main role of the spinocerebellar pathway?

Answer 14

motor coordination - integrated sensory and motor info

Question 15

where si the cerebrocerebellar path lcoaed?

Answer 15

lateral hemisphere

Question 16

what input does the cerbeocerbellar pathway involve?

Answer 16

cortical

Question 17

what is the main role of the cerebrocerebella pathway?

Answer 17

planning + timing of movements

Question 18

where is the vestibulocerebellar path located?

Answer 18

floculonodular love

Question 19

what are the 2 main rolse of the vestibulocerebellar pathway?

Answer 19

1. posture and 2. vestibular reflexes

Question 20

what input does the vestibulocerebellar pathway involve?

Answer 20

vestibular nuclei input

Question 21

what two pathways in the cerebllum are important for smooth coordinated movements?

Answer 21

cerebrocerebellar pathway + spinocerebellar

Question 22

what pathway within the cerebllum is responsibel for balance control?

Answer 22

vestibulocerebellar pathway

Question 23

how do we know if there is dysfunction in the cerebellum

Answer 23

damge or loss of cerebellar tissue

Question 24

what are 4 symptoms of cerrebellar dysfunction?

Answer 24

ataxia - lack of coordination, decomposition + jerky movement
dysmetria - inability to make accurate movements/overshooting undershooting
hypotonia - decrease in muscle tone/resistance
large amounts of sway

Question 25

if someone overshoot when reaching for their class rpetty often where mgiht the issue be? what is this called

Answer 25

their cerebellum - dysmetria

Question 26

what is efference?

Answer 26

motor command sent form motor cortex to body

Question 27

what is teh efference copy?

Answer 27

copy of motor command - sued to update otehr brain regiosn on the acion about to. beperformed

Question 28

Which of the following is an example of re-afference? A) Self-generated motor command B) Externally-generated motor command C) Sensory information from self-generated movement D) Sensory information from an external source

Answer 28

sensory info form self generated movement

Question 29

ex affernce is from ___ source hile re-affernce is form ___. source

Answer 29

externally generated, unexpected vs reafference is self-generated + expected

Question 30

corolary dsicharge represents the ____ we ____ from ___ movmement

Answer 30

re-affernce we EXPECT from self-genrated movement

Question 31

what is corollary discharge used to inhibit

Answer 31

any self-generated mvoemnt taht may interfere with motor task

Question 32

what is the first step of the feedforward moedl?

Answer 32

movement goal is sent to the motor cortex and an appropriate moror plan is selected base don previous experience

Question 33

what 2 things happen in teh feedforward model after the movement ggoal is sent to mtor cortex

Answer 33

1. efference (motor command_ sent to muscles in body to execute mtoor plan base don previous experienve 2. efference copy is sent to the cerebellum to updat on wha tis about to happen

Question 34

where is corollary discharge produced and what is it created from?

Answer 34

cerebellum - created form the efference copy

Question 35

what does corollary discharge represent? what is it used for?

Answer 35

the expected sensory feedback form movement Used to inhibit any resposne to self-generated movement tha tmay interfere with motor task

Question 36

where is re-afference produced?

Answer 36

body

Question 37

corollary discharge represents the ____ sensory feedback we get form the movmment while reafferencce represents the ____

Answer 37

corllary disachrge represents the EXPECTED reaffernce represent the ACTUAL sensory feedback

Question 38

reafference is in the ___ while corllary discharge is in the ___

Answer 38

body cerebellum

Question 39

what is compared in the cerebellum in the feedforward model

Answer 39

corollary discharge and re-afference compares expected vs actual sensory info

Question 40

what happens wh comparison of expected and acutal sensory info within the cerebllum match? what if they dont?

Answer 40

the movement is excuted If they don't, unsuccessful execution - update motor cortex and and adjust motor plan