Compound stimuli in emergent stimulus relations: Extending the scope of stimulus equivalence.
Stimulus equivalence survives when the sample is two items glued together, so you can teach less and get more.
01Research in Context
What this study did
College students learned a match-to-sample game. The sample on each trial was two shapes stuck together. They picked the correct single-shape comparison.
After a few AB→C lessons, the team tested new patterns like AC→B and BC→A. No extra teaching happened.
What they found
Every learner showed perfect emergent choices. Symmetry, transitivity, and equivalence all appeared without direct training.
The compound sample did not break the equivalence effect.
How this fits with other research
Guerrero et al. (2021) added sound to the mix. They used auditory-visual compounds and still got equivalence, showing the effect crosses senses.
Ayres‐Pereira et al. (2025) used nearly identical pictures and a stronger design. They hit 100% success, updating the 1993 shape work with tougher stimuli.
LeFrancois et al. (1993) moved the same idea to students with intellectual disability. Compound samples plus delayed matching taught spelling and equivalence, proving the trick works outside college labs.
Why it matters
You can save hours by teaching with compound samples. One trained relation can yield three or more untrained skills. Try pairing a written word with a picture during early reading lessons. Test for emergent bidirectional naming or intraverbal responses without extra trials. The 1993 data say the relations will hold.
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02At a glance
03Original abstract
Three experiments were conducted to investigate stimulus relations that might emerge when college students are taught relations between compound sample stimuli and unitary comparison stimuli using match-to-sample procedures. In Experiment 1, subjects were taught nine AB-C stimulus relations, then tested for the emergence of 18 AC-B and BC-A relations. All subjects showed the emergence of all tested relations. Twelve subjects participated in Experiment 2. Six subjects were taught nine AB-C relations and were then tested for symmetrical (C-AB) relations. Six subjects were taught nine AB-C and three C-D relations and were then tested for nine AB-D (transitive) relations. Five of 6 subjects demonstrated the emergence of symmetrical relations, and 6 subjects showed the emergence of transitivity. In Experiment 3, 5 college students were taught nine AB-C and three C-D relations and were then tested for nine equivalence (D-AB) relations and 18 AD-B and BD-A relations. Three subjects demonstrated all tested relations. One subject demonstrated the AD-B and BD-A relations but not the D-AB relations. One subject did not respond systematically during testing. The results of these experiments extend stimulus equivalence research to more complex cases.
Journal of the experimental analysis of behavior, 1993 · doi:10.1901/jeab.1993.60-529