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Progressive ratio schedules of reinforcement
Peter R Killeen1, Diana Posadas-Sanchez, Espen Borgå Johansen
1Department of Psychology, Arizona State University, Tempe, AZ 85287-1104, USA. Killeen@asu.edu
Journal of Experimental Psychology. Animal Behavior Processes
|January 23, 2009
Summary
Pigeons
Area of Science:
- Behavioral science and animal cognition.
Background:
- Progressive ratio (PR) schedules are used to study motivation and reinforcement.
- Understanding how response requirements affect behavior is crucial in operant conditioning studies.
Purpose of the Study:
- To investigate pigeon behavior under different progressive ratio (PR) schedules.
- To compare arithmetic (AP) and geometric (GP) progressions in PR schedules.
- To analyze factors influencing response rates and pausing behavior.
Main Methods:
- Pigeons pecked keys to receive grain under PR schedules with increasing response requirements.
- Arithmetic (AP) and geometric (GP) progressions were compared.
- Response rates, pausing, and the effect of contextual cues were analyzed.
Main Results:
- Response rates increased with ratio requirements then decreased linearly (AP) or asymptotically (GP).
- The linear decrease in AP rates was independent of step size.
- Pausing behavior was influenced by prior component length and contextual cues (key colors).
Conclusions:
- Both AP and GP schedules influence pigeon behavior, with distinct patterns in response rates.
- Contextual cues can modulate behavior under PR schedules.
- Existing models require modification to fully explain behavior under GP schedules, incorporating contextual reinforcement.
Related Concept Videos
01:24Reinforcement Schedules
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01:08Timing and Consequences on Behavior
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01:23Primary and Secondary Reinforcers
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01:19Role of Shaping in Operant Conditioning
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01:21Operant Conditioning
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01:23Reinforcement
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