Effects of extinction of a nontarget CS on performance to a target CS.

When a target conditioned stimulus (CS A) is paired with an unconditioned stimulus in the presence of a second, conditioned stimulus (CS B) during compound conditioning trials, the associative strength of CS B can influence the magnitude of the conditioned response (CR) to CS A. For example, extinction of the competing, nontarget CS B can influence the CR to CS A. An enhancement of the CR to the target CS A due to extinction of the nontarget CS B after compound conditioning is sometimes referred to as "recovery from overshadowing" - a type of retrospective revaluation. The present experiments examined retrospective revaluation effects using a conditioned taste aversion procedure. The experiments obtained an effect on the CR to CS A following extinction of CS B. The results are discussed with respect to the comparator hypothesis, within-compound associations, and retrieval as well as other relationships between the target CS and nontarget CS.