Delayed choice responding by pigeons when the correct response is not predictable from the sample stimulus.

Researchers tested pigeons on a delayed-choice task. The birds saw a sample light, waited a few seconds, then had to pick one of two keys.

The catch: the sample gave no hint about which key was correct. The birds had to remember their last choice and the outcome.

Delays ranged from short to several seconds. The team tracked how often the pigeons picked the right key.

At short waits the birds scored above chance. As the delay grew their accuracy slid downward.

The drop matched the classic delay-matching curve, but performance stayed slightly better than in typical matching tasks.

HEARST (1962) ran a similar pigeon delay task. Birds alternated keys after a pause. Both studies show the same decay line as delays stretch, confirming the pattern holds even when the correct answer is unpredictable.

Northup et al. (1991) pushed memory further. They added a distractor key during training and hit 24-hour accuracy. Their trick shows that simple changes can stretch memory far beyond the few-second window seen here.

Haemmerlie (1983) inserted spatial distractors during the wait. Some cues helped, others hurt. Together these papers prove that what happens between sample and choice — be it delay length or extra stimuli — shapes final accuracy.

Your learners face the same problem: hold information across time when the cue no longer points to the answer. Use short delays first, then stretch them gradually. Insert brief self-cues — a quiet rehearse or finger tap — to bridge the gap, just as pigeons use posture. Watch for accidental distractors that can wipe out the memory trace.