Morphine tolerance as habituation.
D000818:Animals; D003214:Conditioning, Classical / Q000187:drug effects; D003463:Cues; D004193:Discrimination Learning / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004361:Drug Tolerance; D006185:Habituation, Psychophysiologic / Q000187:drug effects*; D009020:Morphine / Q000494:pharmacology*; D051381:Rats
D009020:Morphine