The effect of informative feedback on temporal tracking in the pigeon.

Pigeons pecked a key on a variable-interval schedule. A color light told them if their last interresponse time was too fast, too slow, or just right. The catch: the 'just right' window shifted every few sessions. Researchers wanted to see if the color feedback would still control the birds' timing when the rule kept changing.

The colors acted like traffic lights for peck timing. Green might mean 'good speed' in one block, then red took that job in the next. By cycling the rules, the team tested whether feedback can gain stimulus control even while the contingency drifts.

The colors quickly took control. Birds adjusted their peck rate to match the current color rule, even after the rule flipped again. The cyclic change let the feedback stimuli become true discriminative stimuli, not just background noise.

In plain words: feedback works best when the contingency moves. A static rule lets the color fade into irrelevance; a shifting rule keeps it powerful.

Lazar (1977) extends the idea. That team chained three lever responses and gave a unique color after each correct link. When they stripped out the colors, accuracy crashed to chance. Together the studies show: feedback stimuli act as conditioned reinforcers across very different response topographies—timing pecks or chaining levers.

Iwata (1988) adds a timing twist. Pigeons chose the path that showed the informative color sooner, even though the final food delay stayed the same. It dovetails with Fantino (1969): the moment the feedback appears matters as much as its message. Both papers say dynamic or earlier feedback packs more punch.

Snapper et al. (1969) ran in the same year with the same species. They found color dominates form when pigeons learn compound cues. E’s cyclic method may explain why: color gained power because the contingency kept moving, letting color—not form—track the shifting rule.

If you want a cue to control behavior, don’t lock the rule in stone. Cycle the contingency so the stimulus stays informative. In practice, rotate SDs, shuffle prompt levels, or vary the acceptable response window across teaching sets. The learner will ‘track’ the cue like the pigeons tracked the color, and stimulus control will tighten. Keep your reinforcement schedules dynamic if you want your feedback to matter.