Renewal effect: context-dependent extinction of a cocaine- and a morphine-induced conditioned floor preference.
BACKGROUND
Extinction of fear conditioning has been demonstrated to be context dependent. The experiments in this study evaluate whether extinction of a drug-cue association is also context dependent, using a conditioned floor preference procedure.


METHODS
A drug (cocaine or morphine)-floor association was established in a specific context (black or white box). Rats were then given extinction training in which they were exposed to the floors in the conditioning context (Same) or in a different context (Diff) in the absence of the drug. In experiments 1 and 2, during drug-free extinction training, rats were confined to the drug-paired floor on 1 day and the saline-paired floor on the next day over extinction trials. In experiment 3, during drug-free extinction training, rats were given a choice between the drug-paired floor and the saline-paired floor over extinction trials. In all experiments, rats were then returned to the original conditioning context and tested for floor preference.


RESULTS
Extinction of both the cocaine- and morphine-induced floor preference was greater when the rats received extinction training in the same context as conditioning than when they received extinction training in a different context.


CONCLUSIONS
Extinction of associations between external stimuli and the rewarding properties of a drug is context dependent, suggesting that extinction treatments would be most beneficial if conducted in the context in which the original association was established.
Parker
Linda A
LA
Department of Psychology, Wilfrid Laurier University, Waterloo, ON, N2L 3C5, Canada. parkerl@uoguelph.ca
Limebeer
Cheryl L
CL
Slomke
Jessica
J
D000818:Animals; D001245:Association Learning / Q000187:drug effects*; D002755:Choice Behavior / Q000187:drug effects*; D003042:Cocaine / Q000494:pharmacology*; D003214:Conditioning, Classical / Q000187:drug effects*; D003463:Cues; D018765:Dopamine Uptake Inhibitors / Q000494:pharmacology*; D005108:Extinction, Psychological / Q000187:drug effects*; D007274:Injections, Intraperitoneal; D008297:Male; D009020:Morphine / Q000494:pharmacology*; D009294:Narcotics / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012201:Reward; D012931:Social Environment
D018765:Dopamine Uptake Inhibitors; D009294:Narcotics; D009020:Morphine; D003042:Cocaine