Discrimination training: a comparison of two procedures for presenting multiple examples within a fading and non-fading paradigm.
Change the stimulus every trial for speed; stack examples inside each trial for generalization.
01Research in Context
What this study did
Toni and team asked: does it matter how we show many examples when we teach a new discrimination? They compared two ways. One group saw one picture pair per trial, but the pair changed every trial. The other group saw three different pairs inside every single trial.
What they found
Kids who got one pair per trial learned the new discrimination faster. Kids who saw three pairs inside each trial took longer to master the task. But when brand-new pictures showed up later, the second group was better at picking the right one anyway. Speed versus generalization—pick one.
How this fits with other research
Syriopoulou-Delli et al. (2012) later saw the same speed boost when they used the across-trial style to teach identity matching to a child with autism. Bouck et al. (2016) flipped the coin: they piled examples within each trial and got strong rule-following in three boys with autism. Levesque-Wolfe et al. (2021) did the same for safety skills and still saw good generalization. The pattern holds: across-trials for speed, within-trials for transfer.
Why it matters
You now have a simple switch. If the IEP goal is quick mastery—like learning to label red versus blue—run one clear example per trial and rotate fast. If the goal is to use the skill anywhere—like telling safe from unsafe adults—pack two or three examples into each trial and accept the extra sessions. No new materials needed; just rearrange what you already have.
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Join Free →Take one target; run five trials with one picture pair, then five trials with three pairs mixed—track which gives the better generalization probe on Friday.
02At a glance
03Original abstract
When teaching discriminations, many researchers and practitioners recommend presenting multiple examples of both the correct and incorrect stimuli. To test this suggestion, we compared two procedures for presenting multiple examples. In one, multiple examples across trials (ME, Across), one correct (S+) and one incorrect (S-) stimulus were presented each trial; examples then changed across trials. In another procedure, multiple examples within trials (ME, Within), three stimuli (either 2 S+'s and 1 S-, or 1 S+ and 2 S-'s) were presented each trial; examples again changed across trials. Two experiments were conducted to test these procedures. The first procedure used a non-fading program to teach discrimination; the second used a fading procedure. In the first experiment, we taught 10 persons to identify words under these two procedures. The former procedure was superior in acquisition; the latter procedure, however, was better under generalization for most participants. In the second experiment, we presented the two procedures within a fading paradigm. The results replicated those in Experiment 1: ME, Across was better for acquisition, but ME, Within was better for generalization. Results were discussed and follow-up studies suggested.
Research in developmental disabilities, 2003 · doi:10.1016/s0891-4222(02)00171-3