Lecture 13: Contributions of Cerebellum & Basal Nuclei to Motor Function II Flashcards Preview

Human Physiology 2 - Unit 2 - Zach H. > Lecture 13: Contributions of Cerebellum & Basal Nuclei to Motor Function II > Flashcards

Flashcards in Lecture 13: Contributions of Cerebellum & Basal Nuclei to Motor Function II Deck (40)
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1

What does the basal nuclei function to do?

Help to plan and control complex patterns of muscle movements, controlling relative intensities of the separate movements, directions of movements, and sequencing of multiple successive and parallel movements.

2

What does the basal nuclei do?

- plan and execute motor commands in concert with cerebral cortex; help cortex execute subconscious but learned pattern.

- help plan multiple parallel sequential patterns.

- control complex patterns of motor activity.

3

Where does the basal nuclei receive most of its input from?

cerebral cortex

4

Where does the basal nuclei return mots of its output to?

cerebral cortex

5

What is the principle role of the basal nuclei?

Work with corticospinal system to modulate thalamic output to the motor cortex to plan and execute smooth movements.

6

Which paired nuclei make up the basal nuclei?

- striatum
> caudate nucleus
> putamen
- globus pallidus
- substantia nigra
- subthalamic nucleus

7

What are the two major basal nuclei circuits?

- Putamen circuit (direct)
- Caudate nucleus circuit (indirect)

8

What is the putamen circuit (direct pathway) for?

For subconscious execution of learned patterns of movement.

9

Does the putamen circuit (direct pathway) bypass the caudate nucleus?

Yes

10

True or False:
The putamen circuit (direct pathway) is overall excitatory, thus tending to decrease motor activity.

False - tends to increase motor activity (overall excitatory).

11

What is the pathway of the putamen circuit (direct pathway)?

Cerebral cortex -(+)->
Putamen (substantia nigra compacta) -(-)->
Blobus pallidus (internal) and substantia nigra reticularis -(-)->
Thalamic relay nuclei (ventroanterior and ventrolateral nuclei) -(+)->
Primary motor cortex (and premotor/supplementary)

12

In the putamen circuit (direct pathway), the connections between the striatum and the substantia nigra use what neurotransmitter?

Dopamine

13

What receptor does dopamine bind to for an inhibitory effect?

D2 Receptors (indirect pathway)

14

What receptor does dopamine bind to for an excitatory effect?

D1 Receptors (direct pathway)

15

Is the action of dopamine in the putamen circuit (direct pathway) overall excitatory or inhibitory?

excitatory

16

What happens when the putamen is excited?

The putamen inhibits the IGP/SubNigRet and allows the thalamus to send excitatory signals to the motor cortex.

17

You know that the IGP/SubNigRet is normally active, thus sending what signals to the thalamus?

Sends inhibitory signals to the thalamus.

**Putamen inhibits IGP/SubNigRet and allows the thalamus to send excitatory signals to the motor cortex**

18

What does a lesion in the globus pallidus cause?

> Leads to spontaneous and often continuous writhing movements of a hand, an arm, the neck, or the face.

> These movements are called athetosis.

19

What does a lesion in the subthalamic nuclei cause?

> Leads to sudden flailing movements of an entire limb.

> A condition called hemiballismus.

20

What does a lesion in the striatum cause?

Need to look up.

21

What does a lesion in the substantia nigra cause?

> Leads to the common and extremely severe disease of rigidity, akinesia, and tremors known as Parkinson's disease.

22

What is the caudate circuit (indirect pathway) used for?

> Cognitive planning of sequential and parallel motor patterns.

**plays major role in cognitive control of motor activity**

23

What does the caudate circuit (indirect pathway) play a major role in?

In cognitive control of motor activity.

24

Overall, is the caudate circuit (indirect pathway) inhibitory or excitatory?

Over all inhibitory -- tends to decrease motor activity.

25

Does the caudate circuit (indirect pathway) tend to decrease or increase motor activity?

Tends to decrease motor activity.

26

What is the neurotransmitter used between the substantia nigra and caudate nucleus and putamen?

Dopamine (inhibitory)

27

What is the neurotransmitter used between:
caudate nucleus and putamen -->
globus pallidus and substantia nigra

GABA (inhibitory)

28

What is the neurotransmitter used between:
Cortex --> caudate nucleus and putamen?

Acetylcholine (excitatory)

29

What neurotransmitter is used in multiple pathways from the brain stem?

> norepinephrine
> serotonin (inhibitory)
> encephalin

30

What do multiple glutamate pathways provide?

Provide most of the excitatory signals.