ABA Fundamentals

The acquisition of stimulus equivalence in individuals with fragile X syndrome.

Hall et al. (2006) · Journal of intellectual disability research : JIDR 2006
★ The Verdict

Two hours of computerized matching can create new untaught relations for teens with fragile X, but check for emergence early.

✓ Read this if BCBAs teaching academics to adolescents with fragile X or other IDs.
✗ Skip if Clinicians focused only on severe problem behavior with no academic goals.

01Research in Context

01

What this study did

Five teens with fragile X syndrome used a laptop program. The screen showed A-B and B-C matching trials.

After two short sessions the team tested if new relations popped out without direct teaching. They checked math facts and geography facts.

02

What they found

Four teens learned the trained links. One of them showed full equivalence—untrained relations emerged.

Three teens also learned geography sets and all three passed the equivalence test.

03

How this fits with other research

Hopkinson et al. (2003) reviewed 55 kids with ID and little speech. Most formed classes, so naming is not required. The FXS teens fit that pattern.

Tantam et al. (1993) first showed equivalence with college students. Reyer et al. (2006) moved the same lab setup into fragile X—proof the process crosses populations.

O’Connor et al. (2020) later taught kids with autism to link people and emotions. Both studies used single-case designs and saw derived learning, showing the method works across diagnoses.

04

Why it matters

You can run equivalence lessons on a tablet in under two hours. Probe for emergent skills right away—some learners will show them, others will need more training. Start with two linked sets (A-B, B-C) and test before you add more content. This saves teaching time and builds stronger networks for teens with FXS or other IDs.

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Run a quick A-B, B-C matching block on a tablet, then immediately probe for untaught A-C and C-A relations to see if equivalence emerged.

02At a glance

Intervention
stimulus equivalence training
Design
single case other
Sample size
5
Population
intellectual disability
Finding
positive
Magnitude
medium

03Original abstract

BACKGROUND: Few studies have employed stimulus equivalence procedures to teach individuals with intellectual disabilities (IDs) new skills. To date, no studies of stimulus equivalence have been conducted in individuals with fragile X syndrome (FXS), the most common known cause of inherited ID. METHOD: Five adolescents with FXS were taught basic math and geography skills by using a computerized stimulus equivalence training programme administered over 2 days in 2-h sessions. RESULTS: Four of the five participants learned the math relations, with one participant demonstrating stimulus equivalence at post-test. Three of the five participants learned the geography relations, with all three of these participants demonstrating stimulus equivalence at post-test. CONCLUSIONS: These data indicate that computerized stimulus equivalence procedures, conducted in time-limited sessions, may help individuals with FXS learn new skills. Hypotheses concerning the failure of some participants to learn the training relations and to demonstrate stimulus equivalence at post-test are discussed.

Journal of intellectual disability research : JIDR, 2006 · doi:10.1111/j.1365-2788.2006.00814.x