Associative Symmetry, Anti-Symmetry, and a Theory of Pigeons' Equivalence-Class Formation

Abstract

Five experiments assessed associative symmetry in pigeons. In Experiments 1A, 1B and 2, pigeons learned two-alternative symbolic matching with identical sample-and comparison-response requirements and with matching stimuli appearing in all possible locations. Despite controlling for the nature of the functional stimuli and insuring all requisite discriminations, there was little or no evidence for symmetry. By contrast, Experiment 3 demonstrated symmetry in successive (go/no-go) matching, replicating the findings of Frank and Wasserman (2005). In view of these results, I propose that in successive matching, (1) the functional stimuli are stimulus-temporal location compounds, (2) continual nonreinforcement of some sample-comparison combinations juxtaposed with reinforcement of other combinations throughout training facilitates stimulus class formation, (3) classes consist of the elements of the reinforced combinations, and (4) common elements produce class merger. The theory predicts that particular sets of training relations should yield ''antisymmetry'': Pigeons should respond more to a reversal of the nonreinforced symbolic baseline relations than to a reversal of the reinforced relations. Experiment 4 confirmed this counterintuitive prediction. These results and other theoretical implications support the idea that equivalence relations are a natural consequence of reinforcement contingencies.

Associative symmetry in a spatial sample-response paradigm

“…For example, Frank and Wasserman (2005) and Urcuioli (2008) trained pigeons on successive (“go/no-go”) matching in which the samples and comparisons are presented singly at the same spatial location. Responding to the comparisons on one half of the sample-comparison combinations is reinforced, whereas comparison responding on the other half is not.…”

“…When such characteristics are controlled, symmetry does emerge in nonhumans (cf. Frank and Wasserman 2005; Urcuioli 2008). Recently, however, Garcia and Benjumea (2006) reported symmetry in pigeons without controlling for temporal order.…”

How to build an information gathering and processing system: Lessons from naturally and artificially intelligent systems

“…Sidman (see Sidman, 1990; 2000 for example) has proposed that several kinds concepts (such as equivalence relationships like symmetry and transitivity) might arise purely as a consequence of reinforcement contingencies. Experiments using successive matching in pigeons (Urcuioli, 2008) support this theory and further suggest that pigeons might be forming stimulus-temporal location compounds. However, these experiments involved a small number of familiar, simple stimuli, presented in tightly constrained learning environments.…”

On the Origins of Emergent Differential Sample Behavior

“…Interestingly, the Frank and Wasserman (2005) demonstration involved successive (go/no-go) matching in which samples and comparisons appeared singly and at only one location, thus avoiding the location problem inherent in two-alternative tasks. This procedural feature appears to be a necessary, although not a sufficient, condition for observing symmetry (Frank, 2007;Urcuioli, 2007b).…”