Motor Systems (PART 2)

Question 1

The basal ganglia is crucial for the _________________ portion of motion by gating proper initiation of movement.

Answer 1

strategic

Question 2

The loss of dopamine in the ___________________ is responsible for Parkinson’s disease motor deficits (Ex: ? )

Answer 2

Substantia nigra
Shuffling

Question 3

The basal ganglia regulates movement fine-tuning by projecting to the _________________ and the ______________ of the brainstem

Answer 3

thalamus and the tegmentum

Question 4

The basal ganglia is composed of what four things?

Answer 4

1. corpus striatum (caudate and putamen)
2. globus pallidus
3. substantia nigra
4. subthalamic nucleus

Question 5

The ____________________ provides a continuous feedback loop to the cortex for proper initiation and maintenance of motor activity.

Answer 5

basal ganglia

Question 6

Afferents to the basal ganglia arise from the ____________________, ____________________, and ______________________.

Answer 6

prefrontal cortex, parietal, and the motor cortices.

Question 7

The inputs from the afferents are __________________ (______________________) and enter the basal ganglia by the way of the ____________________.

Answer 7

excitatory (glutamatergic)
striatum

Question 8

Inputs to the striatum are
relayed by different circuits throughout the basal
ganglia to produce excitatory efferent fibers from the _________________ to the _______________________________.

Answer 8

putamen
internal globus pallidus (Gpi)

Question 9

The Gpi sends __________________ output to the ____________________ nucleus of the thalamus, which projects a final inhibitory output back to the _______________________.

Answer 9

inhibitory
VL (ventrolateral)
frontal cortex

Question 10

Two basal ganglia circuits are important for regulating movement:
1) ?
2) ?

Answer 10

1) Direct pathway
2) Indirect pathway

Question 11

Direct pathway: _____________ stimulation to START/STOP movement.

Answer 11

excitatory
START

Question 12

The direct pathways is from the ____________ and _____________ to the ____________.

Answer 12

cortex and substantia nigra to the striatum

Question 13

Indirect pathway: uses the _________ pathway with two additional intermediate steps to START/STOP movement

Answer 13

direct
STOP

Question 14

In the direct pathway, the excitatory input is from the ______________________ then inhibits the _________.

Answer 14

striatum
GPi

Question 15

The inhibition of the GPi in the direct pathway releases the ________________ inhibition of the _________________. This produces an excitation at the ____________ to START movement

Answer 15

tonic
thalamus
cortex

Question 16

What are the steps of the direct pathway?

Answer 16

1) cortex (+) and substantia nigra (+)
2) putamen and caudate (striatum) (-)
3) GPi (- tonic)
4) Thalamus (VP Nucleus) (+)
5) motor cortex

Question 17

DIRECT PATHWAY

1. The thalamus is tonically inhibited by the _______
2. The motor cortex activates the __________ to direct movement
3. The striatum ________ the GPi
4. The release of _________ inhibition activates the motor cortex to start movement
5. The ______ further activates the striatum furthering the activation loop

Answer 17

1. GPi
2. striatum
3. inhibits
4. thalamic
5. SNpc

Question 18

In the indirect pathway, _____________ input from the cortex and substantia nigra to the striatum.

Answer 18

excitatory

Question 19

In the indirect pathway, the ___________ then inhibits the _______________________, which inhibits the _____________________ nucleus

Answer 19

striatum
external globus pallidus (Gpe)
subthalamic nucleus

Question 20

In the indirect pathway, the output from the ______________________ to the ________ is stimulatory, producing and increase in _______ inhibition of the thalamus.

Answer 20

subthalamic nucleus
GPi
tonic

Question 21

In regards to the indirect pathway, it leads to an inhibition at the _______ to START/STOP movement.

Answer 21

cortex
STOP

Question 22

What are the steps of the indirect pathway?

Answer 22

1) cortex (+) and substantia nigra (+)
2) putamen and caudate (striatum) (-)
3) GPe (-)
4) subthalamic nucleus (+)
5) GPi (-)
6) motor cortex

Question 23

INDIRECT PATHWAY

1. The ________________ is tonically inhibited by the globus pallidus external
2. When the motor cortex signals to stop movement, the striatum inhibits the _____
3. The release of subthalamic nucleus inhibition activates the _____
4. The Gpi inhibits the _____________: positive input for movement is stopped
5. The subthalamic nucleus also activates the ______
6. The SNpr inhibits the _____________, furthering the inhibition of the loop

Answer 23

1. subthalamic nucleus
2. GPe
3. GPi
4. thalamus
5. SNpr
6. striatum