Stimulus control of the pigeon's ability to peck a moving target.

Two pigeons learned to peck a small key that jumped to a new spot every half-second. The key kept the same color and shape even while it moved.

First the birds got plain reinforcement for pecking a still key. Then the key began hopping around a 3×3 grid. A peck paid off only if the key was red and triangle-shaped, no matter where it landed.

Both pigeons tracked the moving key and rarely pecked the wrong color or form. Accuracy stayed high even when the location changed every 0.5 s.

The birds pecked red-triangle keys and ignored green-circle keys. Movement alone did not control responding; color-plus-form did.

Snapper et al. (1969) showed that color beats form when pigeons pick between static cues. Pisacreta (1982) now shows the same color dominance holds while the cue darts around.

Johnson et al. (1968) found that prior discrimination practice makes later cues stronger. The current study used that principle: it first nailed down a solid red-triangle vs green-circle discrimination, then added speed.

Williams et al. (2002) proved pigeons need only 2 s to tell same from different arrays. Here, half-second exposures were enough to keep accurate tracking, extending the 'brief is enough' idea to moving targets.

If you run matching-to-sample or conditional-discrimination programs, remember that relevant features like color can hold control even when the card or icon hops around the screen. You can use quick location changes to keep clients engaged without hurting accuracy, as long as the key cue stays the same. Try fading in motion only after the basic feature discrimination is rock-solid.