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Published on: January 29, 2017
Schedule-induced drinking as a function of percentage reinforcement
Journal of the Experimental Analysis of Behavior
|March 1, 1975
Summary
Rats showed less drinking when stimuli signaled food, but drank more after food delivery as reinforcement decreased. This suggests a contrast effect in drinking behavior.
Area of Science:
- Behavioral neuroscience
- Animal behavior studies
Background:
- Operant conditioning principles govern motivated behaviors.
- Reinforcement schedules significantly impact response rates and patterns.
- Contrast effects are well-documented in food-reinforced operants.
Purpose of the Study:
- To investigate the influence of percentage reinforcement schedules on drinking behavior in rats.
- To explore whether drinking behavior exhibits a positive-contrast effect analogous to food-reinforced operants.
- To examine the role of conditioned stimuli associated with food delivery in modulating drinking.
Main Methods:
- Rats were trained to lever press under fixed-interval schedules with varying percentage reinforcement for food.
- Drinking behavior was recorded during these sessions.
- Omitted pellet intervals were signaled by light and click stimuli correlated with food delivery.
- Post-pellet drinking was analyzed in relation to the percentage reinforcement schedule.
Main Results:
- Drinking failed to develop in most rats when stimuli signaled food, irrespective of reinforcement percentage.
- Post-pellet drinking duration and amount increased as reinforcement percentage decreased.
- This increase in drinking exceeded that observed under 100% reinforcement.
Conclusions:
- Conditional stimuli associated with food delivery can suppress drinking behavior.
- Decreasing reinforcement schedules enhance post-pellet drinking, mimicking a positive-contrast effect.
- Drinking behavior can serve as a sensitive measure for studying contrast effects in operant conditioning.
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