title: A comparison of the effects of discriminative and Pavlovian inhibitors and excitors on instrumental responding.
abstract: In two experiments, the effects of Pavlovian or discriminative conditioned inhibitors on operant responding were investigated in rats. Experiment 1 found that a Pavlovian conditioned inhibitor for food suppressed food-reinforced lever pressing more than a non-differentially trained control stimulus did. Experiment 2 demonstrated that an operant discriminative inhibitor produced greater suppression of lever pressing than a Pavlovian conditioned inhibitor. Experiment 2 also found that compounding an operant discriminative stimulus (SD) for food-reinforced responding with another SD for food-reinforced responding resulted in more additive summation than when an SD was compounded with a Pavlovian conditioned excitor for food. The results of these experiments support two-factor theories that postulate that incentive and response discriminative processes summate algebraically when the processes are inhibitory or excitatory.
authors.affiliation: Facultad de Psicología, Universidad del País Vasco, Avenida de Tolosa, 70, 20018 San Sebastián, Spain. sebaslombas@hotmail.com
authors.forename: Andrés S
authors.initials: AS
authors.lastname: Lombas
authors.forename: David N
authors.initials: DN
authors.lastname: Kearns
authors.forename: Stanley J
authors.initials: SJ
authors.lastname: Weiss
mesh_terms: D000818:Animals; D003214:Conditioning, Classical; D003216:Conditioning, Operant; D004193:Discrimination Learning; D007266:Inhibition, Psychological; D008297:Male; D051381:Rats; D020318:Rats, Long-Evans; D011930:Reaction Time; D012201:Reward