Preferences among stimulus matches in the pigeon.

Pisacreta (1982) watched three pigeons choose between two colored lights.

Each bird could peck either side. Both sides gave grain, but one color pair always matched.

The study asked: will the birds pick the matching pair more often?

Every pigeon soon favored the matching color pair.

They kept picking the match even when both keys paid off the same.

The color match itself became a powerful cue.

GRADARDANO et al. (1964) saw pigeons split their pecks to match payoff odds. Pisacreta (1982) shows that when a clear stimulus match is present, birds stop splitting and lock onto one choice.

Mellitz et al. (1983) later explained this with a hill-climbing rule: pick the option that just paid off. The steady match choice in Pisacreta (1982) fits that rule because the matching colors kept delivering the last payoff.

Schenk et al. (2020) moved the same idea to humans playing a basketball video game. Players, like pigeons, drifted toward the shot that had just scored. The bird data remind us that simple stimulus cues drive this pattern across species.

When you give clients two tasks, notice which feature they keep choosing. It may not be the richer reward; it could be a tiny matching cue like color or shape. Strip away those extra cues if you want true choice, or add them if you want to boost one option.