Biological approach

• What is the pathway called in addiction?


  Mesolimbic pathway
• What is the mesolimbic pathway?

  • Engage in behaviour
  • Ventral tegmental area
  • Dopamine
  • Nucleus accumbens
  • Excitement
  • Memory trace
• What is the neurotransmitter that causes agitation when elevated?


  Acetylcholine
• What are the receptors that bind with acetylcholine and nicotine?

  Nicotinic acetylcholine receptor (nAchR)
• What do nAchRs do?

  Nicotine and acetylcholine binds to them
• What is the process of nAchRs being shut down and becoming unresponsive to NTs?


  Downregulation
• What happens to the nAchRs?

  Desensitised and don’t respond to nicotine
• What is the nicotine regulation model?


  When smokers go without a cigarette for a long time the nAchRs become resensitised

  More nAchRs are available but not stimulated as there is no more nicotine in the brain so the brain receives more acetylcholine

  This is now withdrawal
• What is another word for resensitised?


  Upregulation
• What is supporting evidence for the role of the dopamine system?

  McEvoy (1995) - SZ patients who were given a drug that blocks dopamine started smoking more to increase dopamine levels
• How is the biological approach reductionist?


  Explains addiction at the simplest level

  Doesn't take into account psychological factors
• How do individual differences affect the biological approach?


  Social smokers smoke regularly but do not undergo withdrawal
• How is the biological approach limited?

  Other neurotransmitters such a GABA may be involved in addiction