23. Morphine as a reinforcing agent: laboratory studies of its capacity to change behavior.
D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects*; D003216:Conditioning, Operant; D004327:Drinking Behavior; D009020:Morphine / Q000494:pharmacology*; D051381:Rats; D012054:Reinforcement, Psychology
D009020:Morphine