Conditioned Place Preference

Conditioned place preference is a form of Pavlovian conditioning used to measure the motivational, pleasurable effect of an object, drug or experience by pairing it with one distinct environment while an unpaired or neutral experience is paired with a different environment; researchers then measure how much time the animal, usually a mouse or rat, chooses to spend in each environment once free to move between them, on the reasoning that more time in the paired environment reflects a learned preference for whatever was associated with it there. The identical procedure run with an aversive stimulus instead of a pleasurable one measures conditioned place aversion. Researchers also distinguish a biased method, in which the environment an animal already prefers least is the one paired with the drug, from an unbiased method, in which the researcher assigns the pairing regardless of the animal's own starting preference. The procedure has also been used to demonstrate that humans develop the same kind of learned place preference, for example people who take therapeutic doses of amphetamine coming to prefer the specific place where they took the drug.