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Fixed-ratio discrimination: effects of response-produced blackouts
Journal of the Experimental Analysis of Behavior
|November 1, 1974
Summary
Pigeons
Area of Science:
- Behavioral psychology and animal cognition.
Background:
- Pigeons were trained on concurrent schedules of reinforcement.
- Differential reinforcement was contingent on side-key responses following fixed-ratio schedules on a center key.
Purpose of the Study:
- To investigate whether pigeons' choice responding was controlled by the number of responses or the time elapsed during fixed-ratio schedules.
- To determine the role of blackout duration in modulating choice behavior.
Main Methods:
- Pigeons were exposed to fixed-ratio 10 and fixed-ratio 20 schedules, with side-key responses determining reinforcement.
- Blackout duration was manipulated to equate the time between the first and last response across different fixed ratios.
- Probe trials with intermediate fixed ratios and blackout durations were conducted.
Main Results:
- Equating the time between the first and last response disrupted side-key choice accuracy, indicating time-based control.
- Asymptotic accuracy improved when time between responses was equated, suggesting time as a critical variable.
- Subsequent probes indicated a transfer of control from time between responses to blackout duration.
Conclusions:
- Time elapsed between responses, rather than the number of responses, significantly influences choice behavior in pigeons.
- Blackout duration serves as a potent stimulus that can control choice responding, potentially overriding time-based control mechanisms.
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