Drive level and cue utilization in a free operant situation with albino rats

Summary Albino rats under either a daily high (2 gms) or moderate (12 gms) food deprivation condition were presented stimuli at the termination of reinforced fixed ratio bar press response chains. Within each drive group, half the animals received a session of brief light-off stimuli accompanied by reinforcement followed by a session of a buzzer and light-off compound stimuli paired with reinforcement. The remaining animals had the buzzer first paired with reinforcement and then the compound stimulus paired with reinforcement. Each stimulus element was tested for its respective control of nonreinforced food-cup approach behavior. These tests demonstrated that the buzzer cue blocked and overshadowed control of approach behavior of the light-off cue. In animals that received the initial light-off conditioning session, overshadowing by the buzzer of the light-off stimulus was less strong in high than moderate drive animals. These results were discussed in terms of Kamin's (1969) findings and Easterbrook's (1959) arousal-cue utilization hypothesis.The present study was supported by a grant given to the senior author from the National Research Council of Canada (APA 7450). The findings of the single stimulus control groups were also presented as a paper in modified form to the Canadian Psychological Association at its annual meeting, 1974, Windsor, Ontario, Canada.