Pigeons demonstrate associative symmetry after successive matching training on one arbitrary and two identity relations (e.g., Urcuioli, 2008). Here, we tested whether identity matching training is necessary for this emergent effect. In Experiment 1, one group of pigeons (Dual Oddity) learned hue-form arbitrary matching and two oddity relations which shared sample and comparison elements with the arbitrary relations. A second (Control) group learned the same hue-form matching task and a second (form-hue) arbitrary task which, together with hue oddity, shared only the samples with the hue-form relations. On subsequent symmetry probe trials, four Dual Oddity pigeons exhibited higher probe-trial response rates on the reverse of the positive than negative hue-form baseline trials, demonstrating associative symmetry. None of the Control pigeons, on the other hand, exhibited associative symmetry. Experiment 2 showed that subsequently changing one of the two oddity baseline relations to identity matching in the Dual Oddity group yielded antisymmetry in three of five pigeons. These results are consistent with predictions derived from Urcuioli’s (2008) theory of pigeons’ stimulus class formation and demonstrate that identity training is not necessary for associative symmetry to emerge after arbitrary matching training in pigeons.


This article may not exactly replicate the final version published in the SEAB journal. It is not the copy of record. This is the pre-peer reviewed version of the following article: Campos, H. C., Urcuioli, P. J., & Swisher, M. (2014). Concurrent Identity Training is not Necessary for Associative Symmetry in Successive Matching. Journal of the Experimental Analysis of Behavior, 101(1), 12-25. http://dx.doi.org/10.1002/jeab.51, which has been published in final form at http://dx.doi.org/10.1002/jeab.51. Authors are not required to remove preprints posted prior to acceptance of the submitted version.


associative symmetry, antisymmetry, successive matching, stimulus classes, stimulus equivalence, key peck, pigeons

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