Equivalence relations between visual stimuli: the functional role of naming.
Rhyming or shared names jump-start equivalence classes in adults.
01Research in Context
What this study did
Researchers asked adults to match pictures that had rhyming names. They wanted to see if shared sounds help people group unrelated pictures together.
Each adult learned to match sample pictures to comparison pictures. Some pairs had names that rhymed, like 'cat' and 'hat'. Other pairs had names that did not rhyme.
What they found
Adults formed equivalence classes only when the picture names rhymed. When names did not rhyme, the adults rarely grouped the pictures together.
The results showed that the sound of a name, not just the picture itself, controls how we sort things.
How this fits with other research
Foti et al. (2015) found the same naming boost using tact training instead of rhyming. Both studies prove that giving stimuli a shared name speeds up equivalence formation in adults.
Chand et al. (2022) later showed that nodality still matters even after you control for naming. Together, the papers say: names open the door, then nodal distance decides how strong the class becomes.
Brown et al. (1994) mapped the order of emergence—symmetry first, then one-node, then two-node. Jolliffe et al. (1999) add the rule: shared names make that whole chain start faster.
Why it matters
Before you run an equivalence program, check what your client already calls the items. If the names rhyme or share a common label, classes form quickly. If they do not, add a brief naming step first. This small tweak can save you hours of conditional-discrimination training.
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02At a glance
03Original abstract
The functionality of verbal behavior in equivalence class formation was demonstrated by training 30 verbally able adults using different combinations of the same easily nameable, yet formally unrelated, pictorial stimuli. Match‐to‐sample baselines for four four‐member classes were established sequentially (i.e., AB‐BC‐CD), with participants in the rhyme condition trained to select comparisons whose normative names rhymed with those of the samples. For the orthogonal condition, class rearrangement was such that on every trial all available comparisons' names rhymed with each other, but not with the name of the sample. In the diagonal condition, stimuli were allocated pseudorandomly as samples and comparisons. Although all participants maintained baseline discriminations prior to emergent testing, equivalence was confined almost exclusively to the rhyme condition, in which it was ubiquitous. These participants also required less training than those in the control conditions, among whom effects of nodal distance were observed most strongly. Subsequent testing presented participants with no‐reinforcement trials involving novel pictorial stimuli, in which one of the available comparisons' names always rhymed with that of the sample. All rhyme participants consistently selected these comparisons. Results indicate that visual stimuli are named, that the phonological properties of those names can influence equivalence class formation, and that the emergence of untrained discriminations may, under certain circumstances, be rule governed.
Journal of the experimental analysis of behavior, 1999 · doi:10.1901/jeab.1999.71-395