Addiction: Big Points

1
Addiction Big Points

• Drug Addicted Individual more prone to relapse
• Drug Addiction is a Brain Disease

2
ACUTE REINFORCING EFFECTS
ADDICTION Chronic relapsing brain disorder
with compulsive, uncontrollable and excessive
drug use. Use becomes focus of activities
and continues despite problems
Dependence Withdrawal
REPEATED SELF- ADMINISTRATION
Tolerance Sensitization Conditioned drug reward
3
Goal Direction
Integration
Action
Conditioning
Motivation
Emotion
From Kaplan and Hammer, 2002
4
Systems (from prior image)

• Mesolimbic Dopaminergic (governs)
• Hippocampus (associations)
• Amygdala (emotional states relate to drug)
• Prefrontal Cortex (Inhibition of behavior)

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NEUROTRANSMITTER AND RECEPTOR MECHANISMS OF DRUGS
OF ABUSE

• DRUG ACTION_____________________________________
  _____
• Opiates Agonist at opioid receptors
• Cocaine Inhibits monoamine reuptake
  transporters
• Amphetamine Stimulates monoamine release from
  vesicles
• Alcohol Activates GABAA receptors, increases
  endogenous opioids
• and inhibits NMDA receptors
• Nicotine Agonist at Ach nicotinic receptors
  (located in VTA)
• Marijuana Agonist at cannabinoid receptors
• Hallucinogens Partial agonist at 5HT2A receptors
• Phenycyclidine (PCP) Antagonist at NMDA receptors

6
Addiction can happen fast

• Administer morphine to a rat four times in a
  certain room
• The rat will always go into the morphine
  associated room
• Nucleus Accumbens affects can be seen after only
  these 4 treatments