Dopamine Evaluation

Question 1

Not all addictive behaviours increase dopamine (weakness)

Answer 1

Paul Stokes et al 2009
Showed no increase in dopamine for some substances like cannabis or alcohol
This suggests that dopamine doesn’t fully explain addictions
HOWEVER
Volkow et al found substances like cocaine consistently increased dopamine levels which shows individuals differences between substances and their effects on dopamine.

Question 2

The complexity of the role of dopamine (weakness)

Answer 2

Dopamine affects not only pleasure but also aversion.
EG- Liberzon et al found dopamine levels increase in war veterans with PTSD when reminded of the battle. This shows dopamine is also involved in fear and avoidance
ALSO
Pruessner et al suggests dopamine is also involved in stress responses , not just rewarding stimuli, which supports the broader role of dopamine in behaviour.

Question 3

Methodological issues in dopamine research (weakness)

Answer 3

David Nutt et al- criticised dopa research bcs of small samples and artificial settings. An example of this is using nicotine inhalers in stream of cigarettes which may not accurately reflect real wold addiction behaviours
ALSO
Zinberg- found the ecological validity is often questioned in lab studies as they fail to replicate the social and environmental factors that influence addiction

Question 4

Dopamines involvement i the reward system (strength)

Answer 4

Dopa plays a central role in the brains reward system.
Volkow et al found addictive substances like cocaine and nicotine increase dopamine levels in the nucleus accumbers which contribute’s to the feeling of pleasure and reinforcing addictive behaviours.
ALSO
Dopamines role in mesolimbic pathway explains why individuals repeat behaviours that trigger to release, such as taking drugs. This highlights its clear link to compulsive reward driven actions.