Differential reinforcement of correct responses to probes and prompts in picture-name training with severely retarded children.
Reinforce every correct probe response during DTT while thinning prompt rewards to make learning faster.
01Research in Context
What this study did
Sanford et al. (1980) worked with three children who had severe intellectual disability.
The team ran discrete-trial picture-name lessons. They tried two reinforcement plans. Plan A: give a reinforcer every time the child answered correctly on a probe trial. Plan B: give prompts on a fixed-ratio schedule and only reinforce some correct answers.
The design flipped back and forth so each child experienced both plans several times.
What they found
Every child learned the picture names fastest when correct probe answers were reinforced every single time.
Prompts stayed on the leaner FR schedule; only probe accuracy earned steady rewards.
How this fits with other research
Jones et al. (1977) showed that two kids can be taught together in DTT and still beat one-to-one efficiency. Sanford et al. (1980) zoomed in on what happens inside each trial: reward the probe, not the prompt.
Boudreau et al. (2015) later compared error-correction styles and found each child had a favorite. Their work extends L et al. by asking, "Once an error occurs, which fix works fastest?"
Richman et al. (2001) moved the same reinforcement logic into small preschool groups. They showed the probe-first, reward-every-time rule still works when three tots answer in chorus.
Why it matters
If you run discrete trials, reinforce every correct probe response while keeping prompts on a thinner schedule. This simple swap can speed up learning without extra materials or time. Try it next session: count probe answers only and deliver a token, praise, or bite for each one right.
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Join Free →Track only independent answers as "probe trials" and give a reinforcer each time the child is right; keep prompted trials on an FR-3 or leaner schedule.
02At a glance
03Original abstract
A systematic sequence of prompt and probe trials was used to teach picture names to three severely retarded children. On prompt trials the experimenter presented a picture and said the picture name for the child to imitate; on probe trials the experimenter did not name the picture. A procedure whereby correct responses to prompts and probes were nondifferentially reinforced was compared with procedures whereby correct responses to prompts and probes were differentially reinforced according to separate and independent schedules of primary reinforcement. In Phase 1, correct responses to prompts and probes were reinforced nondifferentially on a fixed ratio (FR) 6 or 8 schedule; in Phase 2, correct responses to prompts were reinforced on the FR schedule and correct responses to probes were reinforced on an FR schedule of the same value; in Phase 3, correct responses to prompts were reinforced on the FR schedule and correct responses to probes were reinforced on a continuous reinforcement (CRF; every correct response reinforced) schedule; in Phase 4, correct responses to prompts were reinforced on a CRF schedule and correct responses to probes were reinforced on the FR schedule; in Phase 5, a reversal to the conditions of Phase 3 was conducted. For all three children, the FR schedule for correct responses to prompts combined with the CRF schedule for correct responses to probes (Phases 3 and 5) generated the highest number of correct responses to probes, the highest accuracy (correct responses relative to correct responses plus errors) on probe trials, and the highest rate of learning to name pictures.
Journal of applied behavior analysis, 1980 · doi:10.1901/jaba.1980.13-77