Test 4 - Ch. 16

Question 1

What is the job ob the BG?

Answer 1

control circuit
plan and execute voluntary movement

Goal-directed behavior

Question 2

Where does the BG send it’s output?

Answer 2

UMN of cortex and BS

Question 3

What does the BG information first go through before BS to reticulospinal and vestibulospinal?

Answer 3

peduncculopontine

locomotor region

Question 4

Where does outputted go first before reaching cortex from BG?

Answer 4

Thalamus

Question 5

What does the substantial migration do?

Answer 5

contains the cells that make dopamine and dopamine runs the basil ganglia processor. When they die the basil ganglia doesn’t work correctly. *** Powers the basil ganglia.

Question 6

What are the neurotransmitters that are giving input to BG?

Answer 6

excitatory
glutamate
ACl
Serotonin

Question 7

What are the neurotransmitters being output by the BG?

Answer 7

Inhibitory

GABA

Question 8

What runs the processor in the BG?

Where is it synthesized?

What does dopamine do?

Answer 8

dopamine

substantia nigra

determines amount of inhibition, increases/decreases strength of output - globullis pallidus to other regions of brain

Question 9

What are the three loops for the non-motor fxs?

Answer 9

1. goal-directed behavior
2. emotional - BG communicating with frontal lobe
3. social - what is socially appropriate

Question 10

Goal-directed behavior loop
Where?
pathway?
What does it do?
Presentation if damaged?

Answer 10

hair line

BG gets input from frontal lobe- processes it-sends the output to the thalamus - to the cortex - back to the frontal lobe- a continuing loop

Executive function in What I Want To Do, adjusts motor plan based on surroundings, helps with some learning

Hard time setting a goal, hard time making a plan, and influences motor behavior

Question 11

Emotion behavior loop
Where?
pathway?
What does it do?
Presentation if damaged?

Answer 11

Right behind forehead

Helps to incorporate emotions and motivation into motor plan

• reward seeking behavior into motor plan
• helps to make predictions when the outcome is uncertain. (stand next to a steep ledge and get a bad feeling about what could happen, this is the loop)
• integrate with facial expressions.

Problems- cant make predictions, become impulsive and they act without considering the consequences.

Question 12

Social behavior loop

Answer 12

Right behind eyebrows and behind eyes

• helps recognize social cues
• Helps regulates self control (helps adjust behavior and make a motor plan to respect personal space) (not pull a gun when mad in traffic)
• helps piece out what information is relevant and what is not (what can I ignore)

Problems- don’t recognize personal boundaries

Question 13

What are the two motor loops for BG?

Answer 13

oculomotor

motor

Question 14

Occulomotor loop fx?

Answer 14

Helps us to look where I want- create motor plan to move my eyes

Decisions about “spatial attention” and eye movement

Directs eye muscles to “look at” something (“prosaccade”)

Question 15

Motor loop fx?

Answer 15

***Most important- circles to the pre-central gyrus- spins up the plan that finally gets shot down (sent) to the spinal cord.

• it helps regulate muscle contractions
• helps regulate how strongly we contract in light of (what I want to do, what the context is, etc)
• regulates what muscles contract, in what combination they contract, and in what order. Helps create normal synergies.

Question 16

What do the internal circuits of the BG do when you make a plan to move?

Answer 16

It suppresses any movement that doesn’t contribute to what you want to do. It creates normal synergies to help you do what you want to do=the job of the basal ganglia.

Question 17

Where do the three motor loop outputs go to?

Answer 17

motor thalamus - lat corticospinal and rubrospinal UMN
-inhibits motor thalamus

pedunculopontine - goes through the pedunculopontine nucleus down to the brainstem UMN (low degree of voluntary control) helps support movement but take direction from the cortex.
-Brainstem UMN wants to be active- Peduncnucleus doesn’t let the reticulospinal be active, Basal ganglia inhibits inhibitor allows the reticulospinal to be more active- counteracts an inhibitor

midbrain locomotor - control how much activation of the stepping pattern generator.

Question 18

PD

Answer 18

Without the processor the output actually goes up. Leads to…
-too little activation of voluntary muscles (voluntary muscles not facilitated enough)

-too much activation of postural and girdle muscles.

Thalamus inhibits inhibitor which means the postural muscles are too active leads to a very stiff core and limbs that are hard to make move the way that we want to do it.

-too little activation of midbrain locomotor region- walking pattern generator is inhibited so it occasionally fails.

Question 19

HD

Answer 19

Too much voluntary to cortical
Too little BS - postural
Extra movements in voluntary
Core Mm weak

Question 20

What does it mean to feedforward?

Answer 20

have pt. make and think motor plan

Question 21

What are the three incoming sensory systems for postural control?

Answer 21

Vision from cortex

Vestibular from BS/cerebellum

somatosensory from SC