Effects of Stimulus Dimension on the Emergence of Transitivity Relations

The effect of stimuli dimension was assessed on the emergence of transitivity relations by the use of a go/no go procedure and the training of identity relations. Four pigeons were trained under this conditions, varying the dimension of stimuli for each pair. Two pigeons were trained on Hue-Shape (A-B), Shape-Hue (B-C) and Shape-Shape (B-B) relations so probe trials consisted of Hue-Hue (A-C), called Hue Condition, whereas the remaining pigeons were trained Shape-Hue (A-B), Hue-Shape (B-C) and Hue-Hue (B-B) so probe trials consisted of Shape-Shape (A-C), called Shape Condition. Results were presented as frequency and latencies of responses, on training trials and probe trials, showing more responses and shorter latencies for positive training trials on the four pigeons. On probe trials there was a more differentiated response for pigeons in the Hue Condition whereas for pigeons in the Shape Condition, a lack of transitivity was found. Latencies did not differ between pigeons on probe trials. The current findings are in accordance with studies of conditional discrimination and the use of different dimensions, where hue results in quicker acquisition than shapes.