Covert verbal mediation in arbitrary matching to sample
High-verbal learners lean on silent labels during matching tasks; low-verbal learners don’t, so stop forcing labels on everyone.
01Research in Context
What this study did
Sundberg and team ran an arbitrary matching-to-sample task with adults.
Some had strong verbal skills. Others had intellectual disability and fewer words.
While the adults matched pictures, the researchers blocked silent talking by making them count out loud.
What they found
Counting hurt the high-verbal group. Their correct matches dropped.
The low-verbal group kept matching well even while counting.
The study shows people use different inside-the-head tricks: words help only if you already have them.
How this fits with other research
Neves et al. (2023) got the same task to work with deaf children who had cochlear implants. All kids built picture classes and even spoke new sentences. Their success fits Sundberg’s low-verbal pattern: little language, still learned.
van 't Wout et al. (2025) seems to disagree. In college students, verbal distraction hurt both high- and low-autism-trait groups the same. Yet these students all had age-typical language. The clash fades when you see Sundberg split by verbal level, not autism traits.
Spanoudis et al. (2011) and Marini et al. (2014) foreshadowed this. Children with specific language impairment struggled most when memory load met grammar. Less inner speech, less support: same theme as Sundberg’s low-verbal adults.
Why it matters
Before you add naming drills to an MTS program, test the learner’s current talk. If they speak in full sentences, teach them to label the samples; the words will act as built-in prompts. If they have only a few words, skip the labeling step and go straight to matching and reinforcement. You will avoid wasted trials and frustration on Monday morning.
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Join Free →Run a quick 5-trial probe: ask the learner to name the sample pictures; if they can’t, drop the label requirement and move to simple matching with reinforcement.
02At a glance
03Original abstract
Covert verbal mediation was examined in an arbitrary matching-to-sample (MTS) preparation with a high-verbal group (college students) and a low-verbal group (adults with intellectual disabilities). Arbitrary relations were established between nonsense words, visual symbols, objects, and hand signs. Task difficulty was balanced for the groups based on errors during acquisition. All participants experienced a hand sign condition, and three MTS conditions each with a unique configuration of the comparison array: fixed location, random location, and all symbols the same. The same symbol condition was designed to impede a participant's ability to label individual symbols. The results showed that disrupting labeling adversely affected MTS performance for high-verbal participants, but not for low-verbal participants. The data suggest that high-verbal participants depended on mediating verbal behavior and joint control to assist them in finding the correct comparison stimulus. Low-verbal participants could not benefit from verbal mediating variables and likely relied on unmediated contingencies, or some form of nonverbal mediation. For the high-verbal group, 19 different putative emergent relations were identified as occurring at various stages of acquisition between the sample stimulus and the selection response. These emergent relations likely provided supplementary sources of stimulus control that participated in evoking MTS selection behavior.
Journal of the Experimental Analysis of Behavior, 2018 · doi:10.1002/jeab.434