Responding of pigeons under variable-interval schedules of unsignaled, briefly signaled, and completely signaled delays to reinforcement.
Keep the conditioned reinforcer on for the whole delay if the wait is longer than nine seconds.
01Research in Context
What this study did
Six pigeons pecked a key for food on a VI 60-s schedule.
Delays of 0, 3, 9, or 27 s sat between the peck and the grain.
In one condition a 0.5-s light blinked right after the peck.
In another the light stayed on the whole delay.
No signal was also tested.
Each bird lived the delay order alone in a chamber.
What they found
Brief 0.5-s signals kept pecking strong at 3 s and 9 s.
At 27 s most birds quit when the cue was short.
If the light stayed on the whole 27 s the birds kept going.
No signal at all hurt rates even at 3 s.
A tiny cue works, but only if the wait is not too long.
How this fits with other research
Kohlenberg (1973) showed the same rule: a stimulus must last the whole component to keep observing.
Dodd (1984) pushed the limit further—food hours away did not touch current work.
Together the three papers draw a time line: seconds-long cues help, hour-long cues do not.
Nevin et al. (2005) added that faster blinking cues raise response rate but not toughness against disruption.
So brief signals boost speed, yet long steady signals protect staying power.
Why it matters
When you add a token or praise, keep it present until the reinforcer lands if the wait is long.
A quick “good” may work for 3–5 s delays, but 20 s token stacks need the board lit the whole time.
Match signal length to delay length and your learner will keep working.
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02At a glance
03Original abstract
In Experiment 1, three pigeons' key pecking was maintained under a variable-interval 60-s schedule of food reinforcement. A 1-s unsignaled nonresetting delay to reinforcement was then added. Rates decreased and stabilized at values below those observed under immediate-reinforcement conditions. A brief stimulus change (key lit red for 0.5 s) was then arranged to follow immediately the peck that began the delay. Response rates quickly returned to baseline levels. Subsequently, rates near baseline levels were maintained with briefly signaled delays of 3 and 9 s. When a 27-s briefly signaled delay was instituted, response rates decreased to low levels. In Experiment 2, four pigeons' responding was first maintained under a multiple variable-interval 60-s (green key) variable-interval 60-s (red key) schedule. Response rates in both components fell to low levels when a 3-s unsignaled delay was added. In the first component delays were then briefly signaled in the same manner as Experiment 1, and in the second component they were signaled with a change in key color that remained until food was delivered. Response rates increased to near baseline levels in both components, and remained near baseline when the delays in both components were lengthened to 9 s. When delays were lengthened to 27 s, response rates fell to low levels in the briefly signaled delay component for three of four pigeons while remaining at or near baseline in the completely signaled delay component. In Experiment 3, low response rates under a 9-s unsignaled delay to reinforcement (tandem variable-interval 60 s fixed-time 9 s) increased when the delay was briefly signaled. The role of the brief stimulus as conditioned reinforcement may be a function of its temporal relation to food, and thus may be related to the eliciting function of the stimulus.
Journal of the experimental analysis of behavior, 1988 · doi:10.1901/jeab.1988.50-33