Unformatted text preview: s will self stimulate (electrically) o Median Forebrain Bundle (dopamine fibres of passage) o Nucleus Accumbens o Lateral Hypothalamus SelfStimulation & Drug SelfAdministration S @ elfStimulation & Drug SelfAdministration Drug SelfAdministration D @ rug SelfAdministration • Rats will selfadminister cocaine until death (90%) • Heroin less toxic at 36% deaths (Bozarth & Wise, 1985) • Rewarding effect of cocaine is blocked by: o Dopamine antagonists • What makes a substance addictive? • Speed and magnitude of increased dopamine in the nucleus accumbens • “RUSH” Dopamine & Addiction D @ opamine & Addiction • Determined by: o Potency o Route of administration Oral (less potent) Subcutaneous Intramuscular Intranasal (snorting) Inhalation Intravenous (most potent) Lead to the hypothesis that if dopamine causes the sensation of reward then it is responsible for addiction to abused substances “Dopamine Theory of Addiction” Dopamine = Reward D @ opamine = Reward Dopamine may make you WANT to take drugs but is it responsible for obsessive CRAVING? One Limitation (of several) of the Dopamine Theory of Addiction One Limitation (of several) of the Dopamine Theory of Addiction • Aversive stimuli such as: o o o o The stress of handling Electric footshock Tailpinch Aggressive attacks in animals • Increase dopamine neurotransmission Reinforcement Theories Reinforcement Theories Positive reinforcement theor...
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This note was uploaded on 07/06/2010 for the course ANTHRO ANTH106 taught by Professor Lisawynn during the Three '10 term at Macquarie.
- Three '10