Memory for recent behavior in the pigeon.
Pigeons remember their exact peck count for about a minute, and extra pecks during the wait scramble that memory.
01Research in Context
What this study did
Scientists watched pigeons peck a key.
After each short trial they waited 30 or 60 seconds.
Then they asked the bird: did you peck zero, one, or two times?
The pigeon answered by pecking one of three colored keys.
What they found
The birds got it right most of the time for about half a minute.
When the wait grew longer, memory faded.
If extra pecks happened during the wait, the count memory got worse.
How this fits with other research
Adams (1980) already showed pigeons can judge if their peck total is above or below a target.
Julià (1982) moves that idea forward: the bird also stores the exact number for later recall.
Bacon-Prue et al. (1980) found sequence memory drops fast after only 2-4 seconds.
The new study shows count memory lasts much longer, tens of seconds, so different memory rules apply to numbers than to order.
Griffin et al. (1977) taught pigeons a mnemonic strategy to boost recall.
Julià (1982) flips this: instead of helping memory, extra pecks during the delay hurt it, revealing how new responses interfere with old counts.
Why it matters
Your client’s reinforcement history lives in this same short window.
If you wait too long or let other responses pile up, the learner may forget what earned the last reinforcer.
Deliver praise fast and keep extra responses low while teaching new counts or chains.
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Join Free →After the learner completes a counted response requirement, deliver the reinforcer within 15 s and block extra responses so the count stays clear.
02At a glance
03Original abstract
Variations of the symbolic delayed-matching-to-sample procedure were used to study a pigeon's memory for a small number of pecks. In the first experiment a choice of a left or right sidekey after a delay or retention interval was reinforced if a bird had not pecked at all or had pecked exactly once, before the delay, respectively. In the second experiment a choice of a red or green sidekey, regardless of its position, was reinforced if a bird had not pecked at all or had pecked exactly twice, respectively. In the first experiment a bird could orient toward the correct choice during the delay, whereas it could not in the second experiment. In a third experiment a feature-probing method was used to study a pigeon's memory for a number of pecks in the context of certain other pecks. The results showed that a pigeon can remember a small number of pecks for one-half to one minute or more and that the percent correct is a decreasing function of the log retention interval. When a second number of pecks is different from the first number, memory for the first number lasts only a few seconds. When a second number is the same, memory lasts considerably longer. The more recent number of pecks is remembered better. The results are interpreted in terms of a theory which holds that a reinforcer, in general, may act on a subjects' memory for recent behavior to generate patterns of behavior.
Journal of the experimental analysis of behavior, 1982 · doi:10.1901/jeab.1982.38-71