Differential effects of two ways of devaluing the unconditioned stimulus after Pavlovian appetitive conditioning.
Three experiments with rat subjects investigated the effects of two methods of devaluing a food unconditioned stimulus (US) after pairings of an auditory conditioned stimulus (CS) with that US. Experiment 1 found no effect of postconditioning pairings of the food US with lithium chloride (LiCl) on general activity to a tone CS, even though those pairings substantially reduced food consumption. Experiments 2 and 3 compared the effects on conditioned responding of postconditioning pairings of food with LiCl and with high-speed rotation. In these experiments the general activity measure was supplemented by a detailed visual analysis of the rats' behavior. Experiment 2 found that food-rotation pairings had larger effects than food-LiCl pairings on general activity responding and on two detailed behavioral measures but that food-LiCl pairings had larger effects on food consumption and on one behavioral measure. Experiment 3 replicated the findings of Experiment 2 and found that the ability of the CS to serve as a reinforcer for second-order conditioning after US devaluation was reduced more by food-LiCl pairings.
D000818:Animals; D001070:Appetitive Behavior; D001245:Association Learning; D001307:Auditory Perception; D001362:Avoidance Learning; D003214:Conditioning, Classical; D005108:Extinction, Psychological; D008094:Lithium / Q000506:poisoning; D008297:Male; D051381:Rats
D008094:Lithium