W9L1 - Dopamine

Question 1

What are the 2 areas releasing and synthesizing dopamine

Answer 1

1. ) Substantial Nigra (SN)

2. ) Ventral Tegmental Area (VTA)

Question 2

What does VN do

Answer 2

Motor Control

Question 3

What does VTA do

Answer 3

Motivation and emotional responses (reward and addiction)

Question 4

Where does VN and VTA send to

Answer 4

Amygdala, Nucleus Accumbens (NAc), PFC, Straitum

Question 5

How does dopamine synthesize

Answer 5

Tyrosine > Dopamine > Dopamine > Noradrenaline

Question 6

What is tyrosine

Answer 6

Amino acid found in food

Question 7

What is between tyrosine > dopamine

Answer 7

Tyrosine hydroxylase

Question 8

What is between Dopa > Dopamine

Answer 8

Amino Acid Decarboxylase

Question 9

What is between Dopamine > Noradrenaline

Answer 9

Dopamine β-hydroxylase - Synthesize and breaks dopamine

Question 10

What causes PD

Answer 10

Death of dopamine in substantial nigra

Question 11

What are symptoms of PD

Answer 11

Initial: motor tremor; later: cognitive and EF impairments like dementia

Question 12

What is the cure for PD. What is the problem

Answer 12

No cure, but symptoms can be reduce. However, it may cause addictive behaviours.

Question 13

What does “reward” represent

Answer 13

Real, symbolic, or virtual

Question 14

What happens when an unexpected reward is presented

Answer 14

DA burst

Question 15

What happens when an expected reward is presented

Answer 15

No da burst on reward on set, DA burst on beep onset

Question 16

What happens when expected reward but not given

Answer 16

Suppressed da burst on reward on set, DA burst on beep on set (as usual)

Question 17

What does DA code

Answer 17

Reward and Effort Cost

Question 18

What are effort costs

Answer 18

Every other rewarding thing one could be doing

Question 19

When will effort task persistence endure

Answer 19

when the incentive of goals outweighs the cost

Question 20

What happens when there is a low success cognitive task

Answer 20

effort cost > incentive = waste of time

Question 21

Why is gambling addictive

Answer 21

Unexpected large wins = DA coded as positive despite overall loss

Question 22

What is drug addiction

Answer 22

Compulsive drug-taking and drug-taking at expanse of other activities AND despite adverse consequences

Question 23

What does cocaine do biochemcially

Answer 23

Blocks reuptake of dopamine > flood dopamine with system

Question 24

What is ice and speed. What happens biochemically.

Answer 24

Ice: more pure; speed: less pure

Not only blocks, but reverse uptake transporter actively expelling DA and NA out of the neuron

Question 25

What is methylphenidate (ritalin)

Answer 25

Blocks reuptake of DA and noreadrenaline

Question 26

How do addictive drugs work with reward response

Answer 26

Brain always codes reward better than expected due to DA release. Quicker release = More Addictive

Question 27

Does quicker DA release = addictive?

Answer 27

Not always. Might be more important in behaviour and cognitive control rather than euphoric feeling. (Some addictive drugs less DA than other less-addictive)

Euphoric = Opioid system

Question 28

Drugs and Free Will Problem

Answer 28

1. Drugs initiative craving
2. Impaired cognitive control/PFC caused by excessive dopamine
   > Cognitive control + Craving = Addiction