ABA Fundamentals

Brief report: The effect of delayed matching to sample on stimulus over-selectivity.

Reed (2012) · Journal of autism and developmental disorders 2012
★ The Verdict

Even a tiny gap between sample and choice makes kids focus on only one part of the picture.

✓ Read this if BCBAs teaching conditional discriminations or stimulus equivalence to children with autism.
✗ Skip if Clinicians working only on vocal mand training or gross motor skills.

01Research in Context

01

What this study did

Reed (2012) asked kids to play a matching game. First they saw a picture, then after a short wait they picked the same picture from a row.

Some kids had autism. Some were neurotypical. The wait was the only thing that changed.

02

What they found

The short wait hurt everyone. Kids focused on only one part of the picture instead of the whole thing.

Children with autism had the hardest time. Their over-selectivity jumped even higher.

03

How this fits with other research

Lantaya et al. (2018) found a fix. They dropped the wait and used a simple go/no-go task. College students formed stimulus classes without the extra hassle.

Leon et al. (2021) also kept timing tight. They played the sound first, then showed pictures right away. Five of six kids with autism learned faster.

The three studies line up: keep sample and comparison close in time. Delay hurts; immediacy helps.

04

Why it matters

When you run conditional-discrimination drills, place the sample and the choice cards side by side. If you must use tablets, set the delay to zero seconds. This small tweak can cut over-selectivity and speed up learning for kids with autism and typical peers alike.

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Set your matching-to-sample software delay to 0 s and present sample and comparisons together.

02At a glance

Intervention
stimulus equivalence training
Design
quasi experimental
Population
autism spectrum disorder, neurotypical
Finding
negative

03Original abstract

Stimulus over-selectivity occurs when one aspect of the environment controls behavior at the expense of other equally salient aspects. Participants were trained on a match-to-sample (MTS) discrimination task. Levels of over-selectivity in a group of children (4-18 years) with Autism Spectrum Disorders (ASD) were compared with a mental-aged matched typically-developing group. There was more over-selectivity in the ASD group. When retention intervals were added between the sample and comparisons in the MTS task, both groups showed an increased level of over-selectivity, with the ASD group showing a more pronounced effect.

Journal of autism and developmental disorders, 2012 · doi:10.1007/s10803-011-1374-y