Control of pigeons’ matching and mismatching performance by instructional cues

Pigeons were trained on a two-stimulus-shape (a plus and a circle) complex conditional discrimination that required birds to match sample and comparison stimuli on some trials and to mismatch on other trials, depending on the level of chamber illumination (bright or dark). Following acquisition, the birds were transferred to a novel color (red and green) task. For half of the birds, the contingenties between levels of illumination and the match/mismatch response requirements were consistent with training (nonreversal condition). For the remaining birds, the contingencies between levels of illumination and match/mismatch response requirements were the opposite of those established in training (reversal condition). Birds in the nonreversal condition acquired the color match/mismatch task at a significantly faster rate than birds in the reversal condition. These results indicate that relation-based responding (generalized matching/ mismatching) is subject to discriminative control.