title: Effects of an extinguished CS on competition with another CS.
abstract: Three experiments were conducted using a conditioned taste aversion procedure with rats to examine the effect of nonreinforced presentations of a conditioned stimulus (CS) on its ability to compete with a target stimulus for manifest conditioned responding. Two CSs (A and B) were presented in a serial compound and then paired with the unconditioned stimulus. CS A was first paired with the US and then presented without the US (i.e., extinction) prior to reinforced presentation of the AB compound. Experiment 1 showed that A was poor at competing with B for conditioned responding when given conditioning and extinction prior to reinforcement of AB relative to a group that received both A and B for the first time during compound conditioning. That is, an extinguished A stimulus allowed greater manifest acquisition to B. Experiment 2 found that extinction treatment produced a poor CR to the pretrained and extinguished CS itself following compound conditioning. Experiment 3 found that interposing a retention interval after extinction of A and prior to compound conditioning enhanced A's ability to compete with B. The results of these experiments are discussed with regard to different theories of extinction and associative competition.
authors.affiliation: Department of Psychological Sciences, University of Missouri, MO 65211, USA.
authors.forename: Carla H
authors.initials: CH
authors.lastname: Bills
authors.forename: Marsha
authors.initials: M
authors.lastname: Dopheide
authors.forename: Oskar
authors.initials: O
authors.lastname: Pineño
authors.forename: Todd R
authors.initials: TR
authors.lastname: Schachtman
mesh_terms: D000818:Animals; D001245:Association Learning; D001288:Attention; D001362:Avoidance Learning; D003214:Conditioning, Classical; D005108:Extinction, Psychological; D005260:Female; D018021:Lithium Chloride / Q000633:toxicity; D008297:Male; D011939:Mental Recall; D051381:Rats; D017207:Rats, Sprague-Dawley; D012055:Reinforcement Schedule; D013649:Taste
chemical_list: D018021:Lithium Chloride