Addiction- the role of dopamine

Question 1

What are the 3 components?

Answer 1

The mesolimbic pathway
Tolerance and withdrawal
The role of the frontal cortex

Question 2

What is the mesolimbic pathway?

Answer 2

Often called the reward pathway
When engaging in a rewarding activity this pathway is activated creating a pleasurable feeling that reinforces behaviour

Question 3

Mesolimbic pathway- pleasurable behaviour?

Answer 3

Eating
Drinking
Sex
Drugs

Question 4

Where is the mesolimbic pathway?

Answer 4

Dopamine is produced in the VENTRAIL TEGMENTAL AREA (VTA)
and goes to the NUCLEAS ACUMBERT (NAC)

Question 5

Mesolimbic pathway- Joutsa et al?

Answer 5

Dopamine levels increased in participant who were given a gamblic task regardless of the outcome was to win

Question 6

Mesolimbic pathway- Bolieau?

Answer 6

Alcohol increased dopamine levels in the brain

Question 7

What happens when our brain adapts?

Answer 7

Adapts and will strive to reach an equilibrium
It alters the brain function it upsets the balance, brain minimise the effect of drug restoring normal function. If used regularly brain will need to balance

Question 8

What happens when drugs stop being taken?

Answer 8

Brain goes out of balance and withdrawal starts and unpleasant effects start
Drugs will now not be for pleasure but to avoid the withdrawal symptom

Question 9

What happends when drugs become tolerance?

Answer 9

Drug taken repeatedly so effects of drug diminished each rime so a higher dose needed for same effect
-Works with D2 receptors and different receptors are compatible with different neurotransmitter

Question 10

What is D2?

Answer 10

Specific type of neurotransmitter that dopamine attaches to

Question 11

Tolerance and withdrawal- Volkow et al?

Answer 11

Found that in user of cocaine, there was a reduction in both number of D2 receptor in the brain as well as reduction in the release of dopamine

Question 12

Maintaining addiction- the frontal cortex, the responsibility?

Answer 12

Motivation
Judgment
Decision making
Impulse control
Social behaviour

Question 13

The frontal cortex- the impact?

Answer 13

Frontal cortex is implication in the maintain of addiction
One piece of evidence for this is the fact when the drug is no longer taken the negative effects of withdrawal and tolerance have disappeared, relapse can occur

Question 14

The frontal cortex- Volkow et al?

Answer 14

Although dopamine rewarding pathway is the start of addictions develop
This is due to the change in the frontal cortex that turn engaging in a behaviour into addiction

Question 15

The frontal cortex- Robinson and Berridge?

Answer 15

FC linked to higher cognitive functions such as decision making and memory
In addicts, behaviour changes the brain circut that decides to pay attetion to so brain attatches important behaviour associated. So dopaine system plays a role of yjere liking
Explains why addicts dont enjoy experience but cant stop craving

Question 16

The frontal cortex- Bolla et al?

Answer 16

Cocain addicts had abnormal frontal cortec and impared preformance in tasks used in frontal cortex like decision making

Question 17

The frontal cortex- Wang et al?

Answer 17

Addicts have an increased activity i the FC when exposed again to drugs or cues associated with them

Question 18

Evaluation- not all addictive behaviour increase dopamine level?

Answer 18

Theory says that dopamine increase is involved in both creation and maintenance of addictions, but not all addictions show this
Stokes et al- no significant increase in dopamine levels in volunteers taking cannabis
Yoder et al- no consistent increase in dopamine across the participants in study given alcohol

Question 19

Evaluation- to simplistic?

Answer 19

dopamine has many other functions than just happiness than regulating movements, control attention
-BELL 2013 ‘kim kardashian neurotransmitters’ saying its fashionable to blame dopamine for a causing a range of problems where in truth the brain system involved are more complicated than the media provides

Question 20

Strengths of animal study and dopamine?

Answer 20

More ethical than using human rats isolated in good conditions (controlled) meaning it’s valid

Question 21

Weaknesses of animal study’s in dopamine?

Answer 21

Unethical, cant represent human conditioning e.g. gambling
Cant extrapolate results from rats to human

Question 22

Evaluation- why do study’s lack ecological validity?

Answer 22

Don’t represent real life having to use nicotine patches or an inhaler
NUTT et al- sample small substance in a different form so its inaccurate

Question 23

Evaluation- reductionist?

Answer 23

If dopamine, everyone would respond in same way
- We have individual differs function in mesolimbic pathway is ignored
-Dopamine alone isn’t sufficient
-Dopamine explains maintenance but not initiation

Question 24

Evaluation- ethical issues?

Answer 24

Lack of free will- how accountable are adicts for own behaviour especially change to their frontal cortex
Addicts aren’t in control of dopamine system and feel they’ve been hijacked

Question 25

Evaluation- strengths?

Answer 25

Reduces social stigma
Addictions seen as a disease
Addicts may seek and receive help