Symmetry in the pigeon with sample and comparison stimuli in different locations

Abstract

Pigeons typically do not show evidence for symmetry in two-alternative matching-to-sample but do demonstrate this emergent relation in successive (go/no-go) matching-to-sample. Because the sample and comparison stimuli are presented in the same spatial location (viz., on one key) during successive matching training and testing, this may be one reason why pigeons pass tests for symmetry in this paradigm. To evaluate this, one group of pigeons received successive matching training with hue-sample stimuli on the center key and form-comparison stimuli on the left key of a three-key chamber. A control group was trained with all stimuli appearing on the same (left) key. Training also involved concurrent hue- and form-identity successive matching with the same spatial location arrangement as each group’s respective hue–form task. Later, nonreinforced form–hue (symmetry) probes structured in the same way as the baseline trials were given. Of the six birds in each group, five trained with different locations and two trained with constant location responded more to the reverse of baseline positive hue–form combinations than to negative ones in testing. Results confirm the prediction from Urcuioli’s (2008) theory that symmetry should emerge even with varying spatial locations, as long as functional stimuli are held constant.

Transitive and anti-transitive emergent relations in pigeons: Support for a theory of stimulus-class formation

“…Moreover, the data mostly confirm the predictions of Urcuioli's (2008) theory of stimulus-class formation, again reinforcing the principal assumption that the functional matching stimuli for pigeons in these types of tasks are the nominal stimuli plus their ordinal position within a trial (and, of course, their spatial location – cf. Lionello & Urcuioli, 1998; Swisher & Urcuioli, 2013). …”

“…(Note that the theory also recognizes a spatial location component, but that component can be safely ignored when all stimuli appear in the same location – cf. Swisher & Urcuioli, 2013). The theory assumes that successive matching contingencies are conducive to stimulus class formation because non -reinforced sample-comparison combinations occur equally as often as reinforced combinations throughout training (i.e., independent of the level of discriminative performance).…”

Symmetry in the pigeon with sample and comparison stimuli in different locations. II

“…In fact, using different spatial locations for the samples and comparisons provides another, powerful test of Urcuioli's (2008) theory given that spatial location is an important part of the functional matching stimuli (e.g., Lionello & Urcuioli, 1998). Indeed, Swisher and Urcuioli () found evidence for symmetry in pigeons that were trained and tested on successive MTS in which the samples and comparisons were presented in different spatial locations (center and left key, respectively).…”

“…We predicted that the pigeons in Group DL would, like the pigeons in Swisher and Urcuioli (), show evidence of symmetry in Test 1 by responding more to the comparisons on probe trials that were the reverse of the reinforced AB baseline trials (check‐marked trial types in Table ). Likewise, we predicted that pigeons in Group CL would show symmetry in Test 2 because the samples and comparisons comprising the probe trials in their second test likewise appeared in different (center key vs. left key) locations.…”

Associative Concept Learning in Animals: Issues and Opportunities

“…We should be clear at the outset that the term “associative symmetry” is not “procedure‐bound with successive MTS” (Dymond, , p. 154) as evidenced by its use in the paired‐associates (e.g., Murdock, ; Winters, Daggett, & Kologinsky, ), serial recall (Sommer, Rose, & Büchel, ), and choice (Brosgole & Lepak, ; Tomonaga & Fushimi, ; Velasco, Huziwara, Machado & Tomanari, ) literatures. In addition, pigeons' associative symmetry does not require concurrent identity training with the arbitrary matching baseline (Campos, Urcuioli, & Swisher, ) nor does it require that the sample and comparison stimuli be presented in the same location (Swisher & Urcuioli, ).…”