ABA Fundamentals

Intraverbal naming and equivalence class formation in children.

Carp et al. (2015) · Journal of the experimental analysis of behavior 2015
★ The Verdict

Unique intraverbal naming does not promise equivalence—watch for A-C failures and insert direct BC trials.

✓ Read this if BCBAs teaching stimulus equivalence to young neurotypical learners.
✗ Skip if Clinicians working only with tact or listener programs.

01Research in Context

01

What this study did

The team worked with six neurotypical children. They first taught each child a unique name for every picture. Then they ran match-to-sample lessons to build three-member equivalence classes. Last, they tested if the children could pick the correct pictures without prompts.

02

What they found

Three children passed all equivalence tests. Three children failed the final transitivity test even though they could do symmetry. Two of these three passed after the trainers added extra BC trials. Naming alone did not guarantee full equivalence.

03

How this fits with other research

Jolliffe et al. (1999) showed that rhyming names helped adults form classes quickly. Ohan et al. (2015) found that unique names were not enough for some children. The gap shows that naming helps, but the type of name and the learner’s age matter.

Foti et al. (2015) also used naming before equivalence training with adults and saw strong results. Their common names worked better than the unique names used with kids in Ohan et al. (2015). This suggests the naming strategy must fit the learner.

Cohen et al. (1990) and Chand et al. (2022) both showed that one-node relations emerge before two-node relations. The children who failed transitivity in Ohan et al. (2015) followed the same pattern; extra BC training shortened the nodal path and fixed the problem.

04

Why it matters

If a child can match A-B and B-C but fails A-C, do not assume the class is lost. Add direct A-C (BC) trials first. Also, test different naming styles—shared names may work better than unique ones. These small tweaks can save hours of extra teaching.

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Run a quick A-C probe after A-B and B-C training; if the child fails, add five direct A-C match trials before retesting.

02At a glance

Intervention
stimulus equivalence training
Design
single case other
Sample size
6
Population
neurotypical
Finding
mixed

03Original abstract

Six typically developing children between 5 and 7 years of age underwent match-to-sample training to establish three-member equivalence classes after first acquiring a unique name for each stimulus. Horne and Lowe's (1996) naming hypothesis predicts that under those circumstances, match-to-sample training contingencies may establish intraverbal relations between the unique names, which in turn guide correct responses on a subsequent test for stimulus equivalence. Following training of baseline relations (AB and AC), participants received an equivalence test followed by an intraverbal test. Performance on the two tests co-varied, such that three participants passed both tests, and three participants failed repeated administrations of both tests, including a modified version of the equivalence test designed to promote intraverbal responding. The participants who failed the equivalence test, however, did so primarily due to poor performance in transitivity trials, but performed accurately in symmetry trials. After training of a third relation (BC), all three participants performed accurately in a symmetry test for the remaining untrained relations (BA, CA, and CB); two of them in the absence of relevant intraverbal repertoires.

Journal of the experimental analysis of behavior, 2015 · doi:10.1002/jeab.183