Abstract
Seventeen undergraduates were randomly assigned to one of four groups and were exposed first to a multiple fixed-ratio / differential-reinforcement-of-low-rate (mult FR DRL) schedule, then to a multiple fixed-interval / fixed-interval (mult FI FI) schedule. Subjects in the Minimal Instruction condition received no instructions regarding rates of responding. Subjects in the Accurate Instruction condition were instructed to respond rapidly and slowly under the FR and DRL components respectively. under the mult FI FI schedule, a constant reinforcer magnitude was delivered for the Standard FI subjects, whereas reinforcer magnitude varied with number of responses during the interval for the Modified FI subjects. For 3 of 4 subjects in the Minimum Instructions / Standard FI group, higher rates of FI responding occurred under the stimulus previously correlated with FR than that previously correlated with DRL. As a whole, stimulus control by the history effect was stronger for subjects in the Accurate Instruction condition than for those in the Minimum Instruction condition. The effects of instructions were not influenced by the correlation of reinforcer magnitude with response number.
