The effect of fixed and variable blackouts of different durations on responding in fixed interval schedules

UNCG Author/Contributor (non-UNCG co-authors, if there are any, appear on document)
Jean Leighton Hatten (Creator)
The University of North Carolina at Greensboro (UNCG )
Web Site:
Richard L. Shull

Abstract: When the probability of reinforcement varies systematically with elapsed time since some event, rate of responding often varies in a corresponding way. The present experiment investigated whether stimulus events which make equally good predictions of the time to food result in equal average pause durations. For one group of pigeons a fixed-duration blackout was interpolated after each fixed-interval food delivery and the blackout was varied systematically. It was found that the probability of terminating the pause increased early in the fixed interval as the duration of the blackout was increased. The probability of terminating the latency at different times in the 2-min fixed interval on fixed-duration blackout conditions corresponded to that observed during an equivalent portion of a food-initiated fixed interval equal to the sum of the fixed interval and blackout durations. This finding is consistent with the proposal that initiation of the terminal period was under the control of time since food. The comparisons also revealed some control over key-pecking by the key-light onset, with the degree of such control increasing with blackout duration. A second group of pigeons was used to investigate the effects of making the blackout periods variable in duration.

Additional Information

Language: English
Date: 1979
Reinforcement (Psychology)
Pigeons $x Behavior

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